light · sans · structured · cool · dense

You.com

Crisp white developer-doc canvas, custom Lumen Sans, and the indigo `#5368EE` accent — a search API rebrand done as enterprise infrastructure.

By webdesignhot · you.com
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Tokens design.md/v1.5
  • bg #ffffff
  • bg-soft #f6f6f6
  • surface #ffffff
  • surface-alt #fafafa
  • surface-strong #eef0f4
  • surface-hover #f8f8f8
  • text AAA · 18.7 #121212
  • text-strong #000000
  • text-medium #2a2b35
  • text-muted #5e5f6b
  • text-soft #7c7d87
  • text-faint — · 2.3 #a8a9b1
  • on-brand #ffffff
  • on-cta #ffffff
  • brand AA · 4.6 #5368ee
  • brand-hover #3a4ec8
  • brand-strong #3a4ec8
  • brand-deep #293b9a
  • brand-soft #e8ecff
  • brand-faint #f4f6ff
  • brand-glow rgba(83, 104, 238, 0.20)
  • cta-bg #121212
  • cta-bg-hover #2a2b35
  • cta-bg-active #000000
  • cta-text #ffffff
  • link #5368ee
  • link-hover #3a4ec8
  • selected-bg #e8ecff
  • disabled-bg #f6f6f6
  • disabled-text #a8a9b1
  • border — · 1.2 rgba(18, 18, 18, 0.10)
  • border-strong — · 1.5 rgba(18, 18, 18, 0.18)
  • border-soft rgba(18, 18, 18, 0.06)
  • border-focus #5368ee
  • success-bg #dcfce7
  • success-text #15803d
  • warning-bg #fef3c7
  • warning-text #854d0e
  • danger-bg #fee2e2
  • danger-text #b91c1c
  • info-bg #e8ecff
  • info-text #293b9a
  • shadow-rgb 18, 18, 18
  • shadow-blue 83, 104, 238
  • benchmark-our #5368ee
  • benchmark-them #d9d9df
  • benchmark-ground #fafafa
  • benchmark-axis rgba(18, 18, 18, 0.12)
Typography
Ship faster than ever.
display-hero "Lumen Sans" 72px w500
Ship faster than ever.
display "Lumen Sans" 60px w500
Ship faster than ever.
h1 "Lumen Sans" 48px w500
Built for teams that ship.
h2 "Lumen Sans" 30px w500
A complete kit
h3 "Lumen Sans" 24px w500
The quick brown fox jumps over the lazy dog.
h4 "Lumen Sans" 18px w500
The quick brown fox jumps over the lazy dog.
body-large "Lumen Sans" 18px w400
The quick brown fox jumps over the lazy dog.
h5 "Lumen Sans" 16px w500
The quick brown fox jumps over the lazy dog.
body "Lumen Sans" 16px w400
The quick brown fox jumps over the lazy dog.
body-small "Lumen Sans" 14px w400
OUR DESIGN SYSTEM
label-cta "Lumen Sans" 14px w500
OUR DESIGN SYSTEM
caption "Lumen Sans" 13px w400
OUR DESIGN SYSTEM
caption-tabular "JetBrains Mono" 13px w500
npx design-md add linear
code "JetBrains Mono" 13px w400
The quick brown fox jumps over the lazy dog.
benchmark "JetBrains Mono" 13px w500
The quick brown fox jumps over the lazy dog.
eyebrow "Lumen Sans" 12px w500 0.06em
OUR DESIGN SYSTEM
label "Lumen Sans" 12px w500
npx design-md add linear
code-micro "JetBrains Mono" 11px w400
Spacing
  • step-0 1px
  • step-1 2px
  • step-2 4px
  • step-3 6px
  • step-4 8px
  • step-5 10px
  • step-6 12px
  • step-7 16px
  • step-8 20px
  • step-9 24px
  • step-10 32px
  • step-11 48px
  • step-12 64px
  • step-13 80px
  • step-14 96px
  • step-15 128px
Radius
  • micro 2px
  • sm 4px
  • md 6px
  • lg 8px
  • card 12px
  • xl 16px
  • pill 9999px
Components
Text link →
Card preview A complete kit — everything your product needs. Hero, pricing, FAQ, dashboard, docs — every layout your product needs.
New Stable v1.0
Lineage & influences

You.com's site documents the company's strategic pivot from consumer search engine to developer-grade web-data API. Pure white canvas, custom Lumen Sans at weight 500 (open headlines, normal tracking — the brand's most distinctive typographic move), 48px headlines, and near-black `#121212` rectangles for primary CTAs. The indigo `#5368ee` accent carries every benchmark bar — it is the "data is the proof" brand colour. Comparison surfaces use grey `#f6f6f6` chips at 4px radius (the densest, most spreadsheet-grade shape on the page). Lineage runs through Vercel's clean enterprise canvas, Stripe's data-as-marketing hero charts, and Mintlify's developer-doc neutrality.

  • White canvas, near-black rectangle CTAs, and developer-doc neutrality
  • Data-as-marketing — accuracy bars and benchmark plots as the centrepiece; single-confident-action discipline
  • Developer-doc register and the discipline of small radii on data chips
  • Custom-sans + restrained chromatic palette, though Linear runs warmer
  • Open headline tracking; humanist sans cadence
  • Code sample type companion
Export 4 formats · paste-ready
Tailwind

theme.extend block for tailwind.config.js

tailwind.config.js
CSS variables

:root { --bg, --text, --brand, … } you can paste anywhere

design.css
DTCG JSON

W3C Design Tokens Community Group format

design.tokens.json
Figma Variables

Importable into Figma → Variables → Import

figma-variables.json
The file
---
name: You.com
tagline: 'Crisp white developer-doc canvas, custom Lumen Sans, and the indigo `#5368EE` accent — a search API rebrand done as enterprise infrastructure.'
author: webdesignhot
source_url: https://you.com
spec: design.md/v1.5
quality: curated
featured: false
categories: [ai, dev-tools, saas]
tags: [light, sans, structured, cool, dense]
preview_swatch: ['#ffffff', '#5368ee', '#121212']
related: [vercel, supabase, mintlify]
description: 'You.com pivoted from consumer search to a developer-API platform and the marketing site reflects that institutional shift. The canvas is pure white, body and headings set in custom **Lumen Sans** at a calm 500 weight, and the brand accent is a saturated indigo-blue `#5368ee` reserved for benchmark bars and key data points. The aesthetic register is "Vercel + Stripe + a measured-data publication" — small radii (4px on benchmark chips), a 48px headline ladder, and an emphasis on accuracy charts and API documentation rather than a chatty hero. Where Perplexity wraps search-as-essay in cream paper, You.com presents search-as-infrastructure in clean white. The single most distinctive visual decision is the benchmark plot: indigo bars for "our data", neutral-grey bars for competitors, and that chromatic split does the persuasive work of the entire page.'

colors:
  # Primary
  bg: '#ffffff'                          # pure white developer-doc canvas
  bg-soft: '#f6f6f6'                     # competitor-bar grey on benchmark charts
  surface: '#ffffff'                     # default surface
  surface-alt: '#fafafa'                 # benchmark plot / module backdrop
  surface-strong: '#eef0f4'              # divider strength surface
  surface-hover: '#f8f8f8'               # interactive hover wash
  text: '#121212'                        # near-black body text rgb(18,18,18)
  text-strong: '#000000'                 # display-hero strong text (rare)
  text-medium: '#2a2b35'                 # secondary heading emphasis
  text-muted: '#5e5f6b'                  # secondary text rgb(94,95,107)
  text-soft: '#7c7d87'                   # supporting copy
  text-faint: '#a8a9b1'                  # disabled, microcopy
  on-brand: '#ffffff'                    # white label on indigo
  on-cta: '#ffffff'                      # white label on near-black CTA

  # Brand & Accent (indigo)
  brand: '#5368ee'                       # signature saturated indigo — benchmark bars, accents
  brand-hover: '#3a4ec8'                 # darker pressed indigo
  brand-strong: '#3a4ec8'                # alias of hover
  brand-deep: '#293b9a'                  # deepest accent on white
  brand-soft: '#e8ecff'                  # info surface tint
  brand-faint: '#f4f6ff'                 # quietest indigo tint
  brand-glow: 'rgba(83, 104, 238, 0.20)' # focus glow

  # CTA / Action chrome
  cta-bg: '#121212'                      # primary near-black rectangle
  cta-bg-hover: '#2a2b35'                # hover state
  cta-bg-active: '#000000'               # pressed
  cta-text: '#ffffff'                    # label

  # Interactive
  link: '#5368ee'                        # indigo links — the brand peeking through
  link-hover: '#3a4ec8'                  # pressed link
  selected-bg: '#e8ecff'                 # selected item / row tint
  disabled-bg: '#f6f6f6'                 # disabled control fill
  disabled-text: '#a8a9b1'               # disabled label

  # Borders
  border: 'rgba(18, 18, 18, 0.10)'       # default hairline
  border-strong: 'rgba(18, 18, 18, 0.18)' # emphasized rule (button-secondary)
  border-soft: 'rgba(18, 18, 18, 0.06)'  # quietest division
  border-focus: '#5368ee'                # focus-ring indigo

  # Semantic
  success-bg: '#dcfce7'
  success-text: '#15803d'
  warning-bg: '#fef3c7'
  warning-text: '#854d0e'
  danger-bg: '#fee2e2'
  danger-text: '#b91c1c'
  info-bg: '#e8ecff'
  info-text: '#293b9a'

  # Shadow tints
  shadow-rgb: '18, 18, 18'               # near-black tinted shadows
  shadow-blue: '83, 104, 238'            # rare indigo focus glow

  # Benchmark-specific
  benchmark-our: '#5368ee'               # our-data bar fill
  benchmark-them: '#d9d9df'              # competitor-data bar fill (slightly darker than bg-soft)
  benchmark-ground: '#fafafa'            # plot backdrop
  benchmark-axis: 'rgba(18, 18, 18, 0.12)' # axis line

typography:
  display:
    family: '"Lumen Sans", Arial, ui-sans-serif, system-ui, sans-serif'
    weights: [400, 500, 600]
    opentype-features: ['ss01', 'liga', 'kern']
  body:
    family: '"Lumen Sans", Arial, ui-sans-serif, system-ui, sans-serif'
    weights: [400, 500]
    opentype-features: ['kern']
  mono:
    family: '"JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace'
    weights: [400, 500]
    opentype-features: ['tnum', 'zero']
  scale:
    display-hero:    { size: 72, weight: 500, lineHeight: 1.05, tracking: 'normal',  family: display, opentype: 'ss01' }
    display:         { size: 60, weight: 500, lineHeight: 1.08, tracking: 'normal',  family: display }
    h1:              { size: 48, weight: 500, lineHeight: 1.1,  tracking: 'normal',  family: display }
    h2:              { size: 30, weight: 500, lineHeight: 1.2,  tracking: 'normal',  family: display }
    h3:              { size: 24, weight: 500, lineHeight: 1.3,  tracking: 'normal',  family: display }
    h4:              { size: 18, weight: 500, lineHeight: 1.4,  family: display }
    h5:              { size: 16, weight: 500, lineHeight: 1.4,  family: display }
    eyebrow:         { size: 12, weight: 500, lineHeight: 1.4,  tracking: '0.06em',  family: display, transform: uppercase }
    body-large:      { size: 18, weight: 400, lineHeight: 1.55, family: body }
    body:            { size: 16, weight: 400, lineHeight: 1.5,  family: body }
    body-small:      { size: 14, weight: 400, lineHeight: 1.5,  family: body }
    caption:         { size: 13, weight: 400, lineHeight: 1.4,  family: body }
    caption-tabular: { size: 13, weight: 500, lineHeight: 1.4,  family: mono, opentype: 'tnum' }
    label:           { size: 12, weight: 500, lineHeight: 1.3,  family: body }
    label-cta:       { size: 14, weight: 500, lineHeight: 1.2,  family: body }
    code:            { size: 13, weight: 400, lineHeight: 1.55, family: mono, opentype: 'tnum zero' }
    code-micro:      { size: 11, weight: 400, lineHeight: 1.4,  family: mono }
    benchmark:       { size: 13, weight: 500, lineHeight: 1.3,  family: mono, opentype: 'tnum' }

radius:
  micro: 2
  sm: 4                                  # observed benchmark chip radius
  md: 6
  lg: 8
  card: 12
  xl: 16
  pill: 9999

spacing:
  base: 4
  scale: [1, 2, 4, 6, 8, 10, 12, 16, 20, 24, 32, 48, 64, 80, 96, 128]

layout:
  page-width: 1200
  prose-width: 720
  hero-prose-width: 720
  site-gutter: 'clamp(24px, 5vw, 64px)'
  header-height: 64
  grid-columns: 12
  section-rhythm: '80-128px'

components:
  button-primary:
    background: '#121212'
    text: '#ffffff'
    padding: '10px 20px'
    radius: 8
    border: '1px solid #121212'
    font: 'Lumen Sans 500 / 14px'
    hover-bg: '#2a2b35'
    active-bg: '#000000'
    use: 'Get API key / Talk to sales — single near-black rectangle for primary developer conversion'
  button-secondary:
    background: '#ffffff'
    text: '#121212'
    padding: '10px 20px'
    radius: 8
    border: '1px solid rgba(18, 18, 18, 0.18)'
    font: 'Lumen Sans 500 / 14px'
    hover-bg: '#f8f8f8'
    use: 'View docs / Read benchmarks — outlined twin to the primary'
  button-indigo:
    background: '#5368ee'
    text: '#ffffff'
    padding: '10px 20px'
    radius: 8
    border: '1px solid #5368ee'
    font: 'Lumen Sans 500 / 14px'
    hover-bg: '#3a4ec8'
    use: 'Rare brand CTA — used at most once per page on the hero, signals "our data" path'
  button-ghost:
    background: 'transparent'
    text: '#121212'
    padding: '8px 12px'
    radius: 6
    border: 'none'
    font: 'Lumen Sans 500 / 14px'
    hover-bg: '#f6f6f6'
    use: 'Quiet third action — nav links, inline actions'
  card:
    background: '#ffffff'
    border: '1px solid rgba(18, 18, 18, 0.10)'
    radius: 12
    padding: '24px'
    use: 'Feature card — capability tile, pricing tier, doc link'
  card-code:
    background: '#fafafa'
    border: '1px solid rgba(18, 18, 18, 0.06)'
    radius: 12
    padding: '20px'
    use: 'Code sample card — JetBrains Mono on faint-grey plate'
  benchmark-chip:
    background: '#5368ee'
    text: '#ffffff'
    padding: '6px 10px'
    radius: 4
    font: 'Lumen Sans 500 / 12px'
    use: 'Bar segments and key-metric chips on the SimpleQA / FRAMES benchmark plots'
  benchmark-chip-grey:
    background: '#d9d9df'
    text: '#5e5f6b'
    padding: '6px 10px'
    radius: 4
    font: 'Lumen Sans 500 / 12px'
    use: 'Competitor data point — neutral grey, lower contrast'
  input:
    background: '#ffffff'
    border: '1px solid rgba(18, 18, 18, 0.18)'
    radius: 8
    padding: '10px 14px'
    font: 'Lumen Sans 400 / 16px'
    placeholder-color: '#a8a9b1'
    focus-ring: '0 0 0 2px #5368ee'
    use: 'Form fields, search, API key entry'
  badge-pill:
    background: '#e8ecff'
    text: '#293b9a'
    padding: '2px 10px'
    radius: 9999
    font: 'Lumen Sans 500 / 12px'
    use: 'Status pill — Beta / New / Live in nav'
  nav-link:
    background: 'transparent'
    text: '#121212'
    padding: '8px 12px'
    font: 'Lumen Sans 500 / 14px'
    hover-text: '#5e5f6b'
    use: 'Top nav links — quiet, near-black'
  benchmark-plot:
    background: '#fafafa'
    border: 'none'
    radius: 12
    padding: '32px'
    use: 'Horizontal-bar chart container — `#fafafa` ground, no border, indigo + grey bars at 4px radius'

motion:
  ease-standard: 'cubic-bezier(0.4, 0, 0.2, 1)'
  ease-emphasized: 'cubic-bezier(0.2, 0, 0, 1)'
  ease-out: 'cubic-bezier(0.16, 1, 0.3, 1)'
  duration-instant: 80
  duration-fast: 120
  duration-standard: 200
  duration-slow: 320
  duration-page: 400
  duration-bar: 600
  reduced-motion: 'respects prefers-reduced-motion: reduce — bar-chart fill animations become opacity-only, durations halved, no parallax'

breakpoints:
  mobile: 640
  tablet: 1024
  desktop: 1280
  wide: 1440

shadows:
  none: 'none'
  ambient: 'rgba(18, 18, 18, 0.04) 0 1px 3px'
  standard: 'rgba(18, 18, 18, 0.06) 0 4px 12px'
  elevated: 'rgba(18, 18, 18, 0.08) 0 12px 28px -8px'
  dropdown: 'rgba(18, 18, 18, 0.10) 0 16px 32px -12px'
  modal: 'rgba(18, 18, 18, 0.16) 0 24px 48px -12px'
  ring: '0 0 0 2px #5368ee'
  ring-offset: '0 0 0 2px #ffffff, 0 0 0 4px #5368ee'

accessibility:
  contrast-text-on-bg: 17.4              # #121212 on #ffffff — AAA
  contrast-text-on-cta: 17.4             # #ffffff on #121212 — AAA
  contrast-text-on-brand: 4.7            # #ffffff on #5368ee — AA at body
  contrast-text-muted-on-bg: 6.2         # #5e5f6b on #ffffff — AAA
  contrast-link-on-bg: 4.7               # #5368ee on #ffffff — AA at body
  contrast-benchmark-our: 4.7            # #ffffff on indigo bar
  contrast-benchmark-them: 5.6           # #5e5f6b on grey-bar
  focus-ring: '2px solid #5368ee with 2px white offset'
  reduced-motion-honored: true
  keyboard-nav: 'visible focus on every interactive surface; benchmark chart bars are non-focusable decorative elements with adjacent data table for screen readers'
  prose-line-length: 'capped at 720px for hero copy'
  aria-patterns: 'benchmark chart wraps a properly-marked-up <table> for screen readers, with the visual chart marked role=img + aria-label summarising the result; comboboxes use aria-controls + aria-expanded; modals use aria-modal'

dark-mode: null                          # marketing surface is light-only; consumer search at you.com/search has its own theming

lineage:
  summary: 'You.com''s site documents the company''s strategic pivot from consumer search engine to developer-grade web-data API. Pure white canvas, custom Lumen Sans at weight 500 (open headlines, normal tracking — the brand''s most distinctive typographic move), 48px headlines, and near-black `#121212` rectangles for primary CTAs. The indigo `#5368ee` accent carries every benchmark bar — it is the "data is the proof" brand colour. Comparison surfaces use grey `#f6f6f6` chips at 4px radius (the densest, most spreadsheet-grade shape on the page). Lineage runs through Vercel''s clean enterprise canvas, Stripe''s data-as-marketing hero charts, and Mintlify''s developer-doc neutrality.'
  influences:
    - name: Vercel
      role: 'White canvas, near-black rectangle CTAs, and developer-doc neutrality'
      url: https://vercel.com
    - name: Stripe
      role: 'Data-as-marketing — accuracy bars and benchmark plots as the centrepiece; single-confident-action discipline'
      url: https://stripe.com
    - name: Mintlify
      role: 'Developer-doc register and the discipline of small radii on data chips'
      url: https://mintlify.com
    - name: Linear
      role: 'Custom-sans + restrained chromatic palette, though Linear runs warmer'
      url: https://linear.app
    - name: Notion
      role: 'Open headline tracking; humanist sans cadence'
      url: https://www.notion.com
    - name: JetBrains Mono
      role: 'Code sample type companion'
      url: https://www.jetbrains.com/mono/
---

## 1. Visual Theme & Atmosphere

You.com's marketing surface stages the company as **web-data infrastructure for AI builders**. The hero — "The Leading Web Search APIs for AI" — sits in custom **Lumen Sans** at 48px / 500 weight on pure white, with a measured benchmark plot below the fold showing SimpleQA and FRAMES accuracy. The indigo `#5368ee` brand accent fills the You.com bars; competitor bars get a neutral `#d9d9df` grey. That single chromatic decision — saturated indigo for our data, neutral grey for theirs — does most of the persuasive work on the page.

The visual register is *measured-data publication*. Lumen Sans (a humanist face with mild contrast and slightly rounded terminals, custom-designed for the company) reads as Inter's calmer cousin — open headlines, no negative tracking, generous body line-height. Where Stripe compresses headlines, where Linear tightens tracking, where Vercel goes near-Inter, You.com leaves headlines *open*. The lack of negative tracking is itself a brand choice: the type breathes, and the breath signals "we're confident in our numbers, we don't need typographic compression to demand attention."

The chromatic palette is narrow by design. White, near-black `#121212`, neutral grey `#f6f6f6`, and one saturated indigo `#5368ee`. The indigo never appears as a CTA fill (those are near-black rectangles); it appears as the colour of *proof* — benchmark bars, accuracy chips, citation links. The "our data is indigo, their data is grey" pattern propagates throughout the site.

The 4px benchmark-chip radius is the densest, most spreadsheet-grade shape on the page — most modern sites land at 6–8px minimum on chips. The 4px choice signals "this is data, not decoration." Cards round at 12px, buttons at 8px — both standard, neither expressive. The shape vocabulary is conservative on purpose; the data is the protagonist.

Atmospheric vocabulary: *developer-doc-white, Lumen-open, indigo-proof, near-black-rectangle-CTA, accuracy-bar, benchmark-publication, Vercel-cousin-Mintlify-cousin, search-as-infrastructure, our-data-vs-theirs.*

**Key Characteristics**
- Pure white `#ffffff` developer-doc canvas
- Custom **Lumen Sans** at weight 500 with **normal tracking** (open, not compressed)
- Saturated indigo `#5368ee` reserved for "our data" — never a CTA fill
- Near-black `#121212` rectangle CTAs at 8px radius
- 4px benchmark chip radius — densest shape on the page
- `#fafafa` plot backdrop with `#5368ee` + `#d9d9df` bar pair
- 12px cards with hairline borders — flat, no shadow
- Single-family type system (Lumen Sans + JetBrains Mono companion)
- 720px hero prose width — broadsheet narrow on a 1200px page
- Data-first hierarchy — the benchmark plot is the hero, not the headline

## 2. Color Palette & Roles

### Primary

- **bg** `#ffffff` — pure white developer-doc canvas, the defining surface.
- **text** `#121212` — near-black body text; warmer than pure `#000`.
- **bg-soft** `#f6f6f6` — competitor-bar grey on benchmark plots; also used for code-sample plates.
- **surface-alt** `#fafafa` — benchmark plot backdrop; one notch lighter than `#f6f6f6`.
- **cta-bg** `#121212` — primary CTA near-black rectangle.
- **on-cta** `#ffffff` — white label on near-black.

### Brand & Accent (indigo)

- **brand** `#5368ee` — signature indigo; benchmark bars, link colour, brand mark.
- **brand-hover** `#3a4ec8` — darker pressed indigo for buttons and links.
- **brand-deep** `#293b9a` — deepest accent on white (badge text, emphasis).
- **brand-soft** `#e8ecff` — info surface tint, status pill bg.
- **brand-faint** `#f4f6ff` — quietest indigo tint, used as section background in rare promotional bands.
- **brand-glow** `rgba(83, 104, 238, 0.20)` — focus glow effect.

### Interactive

- **link** `#5368ee` — saturated indigo, underline on hover.
- **link-hover** `#3a4ec8` — pressed state.
- **selected-bg** `#e8ecff` — selected nav item, selected row in spec tables.
- **disabled-bg** `#f6f6f6` — disabled fill.
- **disabled-text** `#a8a9b1` — disabled label.
- **focus-ring** `#5368ee` — 2px solid with 2px white offset.

### Neutral Scale

- **near-black** `#121212` — primary text.
- **slate-medium** `#2a2b35` — secondary heading emphasis.
- **slate-muted** `#5e5f6b` — secondary copy, the most-used muted tone.
- **slate-soft** `#7c7d87` — supporting copy.
- **slate-faint** `#a8a9b1` — disabled, microcopy.
- **slate-line** `#d9d9df` — competitor bar fill (also a strong divider).

### Surface & Borders

- **surface-0 (page)** — `#ffffff` pure white.
- **surface-1 (panel)** — `#fafafa` benchmark plot backdrop.
- **surface-2 (chip-grey)** — `#f6f6f6` for code samples and competitor data.
- **surface-3 (hover)** — `#f8f8f8` interactive hover state.
- **border** `rgba(18, 18, 18, 0.10)` — default hairline.
- **border-strong** `rgba(18, 18, 18, 0.18)` — emphasized rule, used on button-secondary.
- **border-soft** `rgba(18, 18, 18, 0.06)` — quietest division.

### Shadow Colors

You.com is **flat-first**. Marketing surface uses tonal layering and hairline borders for 95% of depth. The single place a real shadow appears is the navigation dropdown (`rgba(18, 18, 18, 0.10) 0 16px 32px -12px`) and the rare modal. Shadows are **near-black tinted**, never indigo-tinted.

### Semantic

- **success** — `#dcfce7` / `#15803d`. Used for "API key generated", "Account active".
- **warning** — `#fef3c7` / `#854d0e`. Used for rate-limit warnings.
- **danger** — `#fee2e2` / `#b91c1c`. Used for failed requests, account issues.
- **info** — `#e8ecff` / `#293b9a`. Reuses brand-indigo pair; signals "You.com info" tone.

### Benchmark-specific

The chart pair is doctrinal:
- **benchmark-our** `#5368ee` — saturated indigo, "our number".
- **benchmark-them** `#d9d9df` — neutral grey, "their number". Slightly darker than `#f6f6f6` to remain visible on `#fafafa` plot ground.
- **benchmark-ground** `#fafafa` — plot backdrop.
- **benchmark-axis** `rgba(18, 18, 18, 0.12)` — axis lines, gridlines.

## 3. Typography Rules

### Font Family

- **Display & Body**: **Lumen Sans**, a custom humanist sans with mild contrast and modestly rounded terminals. Loaded with weights 400 / 500 / 600. Lumen reads as Inter's calmer, more-rounded cousin — slightly warmer, slightly more open. Fallback chain: `Arial → ui-sans-serif → system-ui → sans-serif`.
- **Mono**: **JetBrains Mono** for code samples and rare benchmark numerals. Fallback to `ui-monospace, "SF Mono", Menlo, Consolas, monospace`.
- **OpenType features**: `kern` always; `ss01` on display headlines (cleaner alt-glyphs); `tnum` + `zero` mandatory on mono for legible numerics in code samples.

### Hierarchy

| Role | Font | Size | Weight | Line Height | Letter Spacing | OT Features | Notes |
|---|---|---|---|---|---|---|---|
| display-hero | Lumen Sans | 72 | 500 | 1.05 | normal | ss01 | Rare hero — major page openers |
| display | Lumen Sans | 60 | 500 | 1.08 | normal | — | Section openers |
| h1 | Lumen Sans | 48 | 500 | 1.1 | normal | — | Standard hero ("The Leading Web Search APIs for AI") |
| h2 | Lumen Sans | 30 | 500 | 1.2 | normal | — | Section heading |
| h3 | Lumen Sans | 24 | 500 | 1.3 | normal | — | Subsection |
| h4 | Lumen Sans | 18 | 500 | 1.4 | normal | — | Card heading |
| h5 | Lumen Sans | 16 | 500 | 1.4 | normal | — | Inline heading |
| eyebrow | Lumen Sans | 12 | 500 | 1.4 | 0.06em | uppercase | Section label |
| body-large | Lumen Sans | 18 | 400 | 1.55 | normal | — | Lede |
| body | Lumen Sans | 16 | 400 | 1.5 | normal | — | Default body |
| body-small | Lumen Sans | 14 | 400 | 1.5 | normal | — | Secondary copy |
| caption | Lumen Sans | 13 | 400 | 1.4 | normal | — | Helper text |
| caption-tabular | JetBrains Mono | 13 | 500 | 1.4 | normal | tnum | Spec-row data |
| label | Lumen Sans | 12 | 500 | 1.3 | normal | — | Form labels, tags |
| label-cta | Lumen Sans | 14 | 500 | 1.2 | normal | — | Button text |
| code | JetBrains Mono | 13 | 400 | 1.55 | normal | tnum zero | API code samples |
| code-micro | JetBrains Mono | 11 | 400 | 1.4 | normal | — | Footnote, citation |
| benchmark | JetBrains Mono | 13 | 500 | 1.3 | normal | tnum | Accuracy values, chart labels |

### Principles

- **Normal tracking on display.** Lumen Sans headlines hold at `tracking: normal` — no `-0.02em` compression. The open headline tone is the brand's most distinctive typographic move.
- **500 is the heading weight.** Never 600 or 700 on display; never 400 on h1-h3. The single weight stripe gives the page a calm authority.
- **Single-family type system.** No serif counterpoint, no editorial italic. Lumen Sans + JetBrains Mono is the entire vocabulary.
- **Body line-height of 1.5–1.55.** Slightly more leading than developer-doc default (1.4–1.5). Reads as comfortable rather than dense.
- **Mono for code only — and benchmark labels.** JetBrains Mono surfaces only inside code samples or chart-axis labels. The marketing prose stays sans throughout.
- **Numbers in mono with `tnum`.** Tabular numerals are mandatory on benchmark values and code samples — every chart aligns numerically.
- **No italic body emphasis.** Use weight 500 on body for emphasis; italic is reserved for citation captions.

## 4. Component Stylings

### Buttons

**Primary (near-black rectangle)** — `#121212` bg, `#ffffff` text, 8px radius, Lumen Sans 500 / 14px, padding `10px 20px`. Hover lifts to `#2a2b35`; active drops to `#000`. Used for: "Get API key", "Talk to sales", "Create account".

**Secondary (outlined rectangle)** — `#ffffff` bg, `#121212` text, `1px rgba(18, 18, 18, 0.18)` border, 8px radius, identical typography to primary. Hover wash `#f8f8f8`. Used for: "View docs", "Read benchmarks", "Contact us".

**Indigo (brand CTA)** — `#5368ee` bg, `#ffffff` text, 8px radius. Hover `#3a4ec8`. Reserved for the rare brand-hero CTA — appears at most once per page, signals "try our data" path.

**Ghost** — transparent, `#121212` text, 6px radius, `8px 12px` padding. Hover wash `#f6f6f6`. Used for nav links, inline actions.

### Cards

**Feature card** — `#ffffff` bg, `1px rgba(18, 18, 18, 0.10)` border, 12px radius, `24px` padding, no shadow. Used for capability tiles, doc links, pricing tiers.

**Code sample card** — `#fafafa` bg, `1px rgba(18, 18, 18, 0.06)` border, 12px radius, `20px` padding. JetBrains Mono content inside. Copy button at top-right.

**Benchmark card** — `#fafafa` bg, no border, 12px radius, `32px` padding. Contains a single horizontal-bar chart with You.com indigo + competitor grey bars.

### Badges, Tags, Pills

**Benchmark chip (indigo)** — `#5368ee` bg, `#ffffff` text, Lumen Sans 500 / 12px, **4px radius**. The signature data shape — used on bar segments and key-metric chips.

**Benchmark chip (grey)** — `#d9d9df` bg, `#5e5f6b` text, same typography, 4px radius. The competitor counterpart.

**Status pill (indigo soft)** — `#e8ecff` bg, `#293b9a` text, Lumen Sans 500 / 12px, pill radius (9999). Used for nav `Beta`, `New`, `Live` indicators.

### Inputs & Forms

**Default input** — `#ffffff` bg, `1px rgba(18, 18, 18, 0.18)` border, 8px radius, `10px 14px` padding, Lumen Sans 400 / 16px, `#a8a9b1` placeholder. Focus ring `0 0 0 2px #5368ee` with 2px white offset.

**Form labels** — Lumen Sans 500 / 14px, `#121212`, `4px` margin-bottom from input.

**Helper text** — Lumen Sans 400 / 13px, `#5e5f6b`, `4px` margin-top from input.

**Error state** — border `#fee2e2`; helper text flips to `#b91c1c`.

### Navigation

**Top nav** — 64px header height, `#ffffff` bg with `1px rgba(18, 18, 18, 0.06)` bottom border (only on scroll), Lumen Sans 500 / 14px / `#121212` links. Hover lightens to `#5e5f6b`. Right cluster: "Sign in" ghost link + "Get API key" near-black rectangle CTA.

**Footer nav** — Lumen Sans 400 / 14px / `#5e5f6b`, 4-column grid on desktop.

### Benchmark Plot (the signature module)

**Chart container** — `#fafafa` bg, no border, 12px radius, `32px` padding. Chart title in Lumen Sans 500 / 24px above. Source caption in JetBrains Mono 11px / `#7c7d87` below.

**Bar (our)** — `#5368ee` fill, 4px radius, height ~24px. Bar label inside-end if fits, else outside-end. Label in Lumen Sans 500 / 13px / `#ffffff` (inside) or `#121212` (outside).

**Bar (their)** — `#d9d9df` fill, 4px radius, same height. Label `#5e5f6b`.

**Axis** — `rgba(18, 18, 18, 0.12)` line, JetBrains Mono 11px tick labels.

### Tooltips

**Tooltip** — `#121212` bg, `#ffffff` text, 6px radius, Lumen Sans 400 / 13px, `8px 12px` padding, `200ms` fade.

### Toasts

**Toast** — `#ffffff` bg, `1px rgba(18, 18, 18, 0.10)` border, 8px radius, ambient shadow, `12px 16px` padding. Slides up from bottom-right.

### Modals

**Modal** — `#ffffff` panel, 12px radius, modal shadow, `40px` padding. Backdrop `rgba(18, 18, 18, 0.5)`.

## 5. Layout Principles

### Spacing System

Base unit **4px**. Scale: `1, 2, 4, 6, 8, 10, 12, 16, 20, 24, 32, 48, 64, 80, 96, 128`. Component padding lives in 8–24; section padding 80–128. The system reads as developer-doc dense — slightly tighter than Anthropic, slightly looser than Stripe.

### Grid & Container

- **Page max-width**: 1200px, centred, `clamp(24px, 5vw, 64px)` site gutter.
- **Hero prose-width**: 720px max — broadsheet narrow.
- **Grid columns**: 12, 24px gutter.
- **Feature grid**: 3-up cards on desktop with equal-width columns.
- **Benchmark plot**: full-width within container.

### Whitespace Philosophy

Between sections: 80–128px on desktop, 48px on mobile. Within sections: 24–48px between groups. The page is organised as **hero + benchmark plot + accuracy claim + 3-up capability rail + API code sample + pricing/contact**. The benchmark plot lives near the top of the fold — it's the proof, not the conclusion.

### Section Cadence

The page alternates **white** and **`#fafafa` faint-grey** bands every 2–3 sections. The benchmark plot uses the `#fafafa` band so the chart's plot backdrop continues seamlessly into the section. There is no dark-mode brand band — light throughout.

## 6. Shapes & Radius Scale

| Tier | Value | Use |
|---|---|---|
| Micro | 2px | Hairline indicators, focus inner-stroke |
| Small | 4px | **Benchmark chips, bar segments** — the signature dense shape |
| Medium | 6px | Ghost buttons, dropdown items |
| Standard | 8px | Buttons (primary, secondary, indigo), inputs |
| Card | 12px | Feature cards, code sample cards, benchmark plot container |
| Featured | 16px | Reserved (rare hero modules) |
| Pill | 9999px | Status pills, nav badges |

The 4px benchmark-chip radius is the densest shape on the page and the most distinctive — most modern sites land at 6–8px minimum on chips and pills. The tighter radius signals "data, not decoration." Cards hold at 12px (matching Stripe and Notion); buttons at 8px (matching Vercel and Linear).

## 7. Depth & Elevation

| Level | Treatment | Use |
|---|---|---|
| 0 (flat) | No shadow, no border | Page bg, hero copy |
| 1 (hairline) | `1px rgba(18, 18, 18, 0.10)` border | Default cards |
| 2 (tonal) | `#fafafa` bg tint, no shadow | Code panels, benchmark plot section |
| 3 (ambient) | `rgba(18, 18, 18, 0.04) 0 1px 3px` | Toast, light hover |
| 4 (dropdown) | `rgba(18, 18, 18, 0.10) 0 16px 32px -12px` | Nav dropdown menu |
| 5 (modal) | `rgba(18, 18, 18, 0.16) 0 24px 48px -12px` | Modal panel |

### Shadow Philosophy

You.com is **flat-first**, like Cartesia and Vercel. Marketing surface depth comes from tonal layering plus hairline borders. The benchmark plot — the most data-dense module — has *no border, no shadow*; it relies on the `#fafafa` plot ground to define its boundaries against the white page. Real shadows live only on dropdowns and modals, both **near-black tinted at low opacity**. The indigo brand accent never appears in shadow — it's reserved for fill and focus-ring.

## 8. Interaction & Motion

### Easing curves

- **Standard** — `cubic-bezier(0.4, 0, 0.2, 1)` — default for hover, focus.
- **Emphasized** — `cubic-bezier(0.2, 0, 0, 1)` — incoming elements, modals.
- **Out** — `cubic-bezier(0.16, 1, 0.3, 1)` — overshoot-free decelerate for benchmark-bar fill animations.

### Duration buckets

- **Instant** — 80ms — focus ring, micro-state.
- **Fast** — 120ms — hover bg shift.
- **Standard** — 200ms — default transitions.
- **Slow** — 320ms — modal opens, dropdowns.
- **Page** — 400ms — route transitions.
- **Bar** — 600ms — benchmark bar fill animation (the signature page-scroll moment).

### Per-component micro-states

- **Button hover** — bg shifts via `120ms ease-standard`. No translate, no scale.
- **Card hover** — border-soft brightens from `rgba(18, 18, 18, 0.10)` to `rgba(18, 18, 18, 0.18)` over `200ms`.
- **Link hover** — colour stays indigo, underline reveals via `text-decoration` over `120ms`.
- **Input focus** — focus-ring fades in `80ms`; border swaps to `#5368ee`.
- **Benchmark bar fill** — bars animate width `0 → final` over `600ms ease-out` when scrolled into view via IntersectionObserver. This is the page's signature moment — the data resolves before the user's eyes.
- **Toast** — slides up 8px and fades 0 → 1 over `320ms`.
- **Modal** — backdrop fades 0 → 0.5 over `200ms`; panel scales `0.98 → 1` simultaneously.

### Page transitions

Marketing pages use SPA-style transitions with `400ms ease-standard` fade-through. Section anchors use `scroll-behavior: smooth`.

### Reduced-motion strategy

`prefers-reduced-motion: reduce` is fully honoured. The benchmark bar fill animation **disables entirely** — bars render at final width with no animation (this is the most consequential reduced-motion override). Translate transforms become opacity fades. Smooth scroll disables.

## 9. Accessibility & A11y

### Contrast pairs (computed)

| Pair | Ratio | WCAG |
|---|---|---|
| `#121212` on `#ffffff` (body) | 17.4:1 | AAA |
| `#ffffff` on `#121212` (CTA) | 17.4:1 | AAA |
| `#5e5f6b` on `#ffffff` (muted) | 6.2:1 | AAA |
| `#5368ee` on `#ffffff` (link / indigo CTA) | 4.7:1 | AA at body |
| `#ffffff` on `#5368ee` (indigo bar label) | 4.7:1 | AA at body |
| `#293b9a` on `#e8ecff` (badge) | 7.5:1 | AAA |
| `#5e5f6b` on `#d9d9df` (competitor bar label) | 5.6:1 | AA |

### Focus indicators

**2px solid `#5368ee`** with **2px white offset** on every interactive surface. Inputs additionally swap their border to `#5368ee` on focus. The indigo focus is visually distinct from any neutral UI colour.

### ARIA patterns

- **Benchmark chart** — wraps a properly-marked-up `<table>` for screen readers (rows: model name, accuracy, p-value); the visual chart is `role="img"` + `aria-label="Benchmark chart: You.com 86% accuracy on SimpleQA versus competitors at 78%, 71%, 65%"`. Keyboard users tab into the table; visual users see the chart.
- **Combobox** — `role="combobox"` + `aria-controls` + `aria-expanded` + `aria-activedescendant`.
- **Modal** — `role="dialog"` + `aria-modal="true"` + `aria-labelledby` + `aria-describedby`. Initial focus on first input; ESC dismisses.
- **Tooltip** — `role="tooltip"` + `aria-describedby` from trigger.
- **Tabs** — `role="tablist"` + `role="tab"` + `aria-selected` + arrow-key navigation.

### Keyboard navigation

- Tab order matches reading order — header, hero CTA, benchmark plot (skipped, links to data table), feature cards, footer.
- ESC closes modals, dropdowns.
- Arrow keys move within tab-lists, dropdowns, comboboxes.
- Skip-to-content link on first Tab.

### Screen reader hints

- Benchmark chart announces full data via the adjacent `<table>` markup; users hear "You.com: 86 percent accuracy. Competitor A: 78 percent..."
- The 4px-radius benchmark chip uses `aria-label` describing the metric ("Indigo chip indicating You.com's 86% accuracy on SimpleQA").
- All decorative SVG illustrations are `aria-hidden="true"`.
- Code samples wrap in `<pre><code>` with `aria-label="Python example using You.com Search API"`.

### Reduced motion

Honoured globally. The benchmark bar fill animation is the most affected — bars render at final width with no animation when `prefers-reduced-motion: reduce` is set.

## 10. Responsive Behavior

### Breakpoints

| Name | Min-width | Notes |
|---|---|---|
| mobile | 0 | Single column, 24px gutter, hero at 32px |
| tablet | 640px | 2-up feature grid, hero at 36px |
| desktop | 1024px | 3-up grid, hero at 48px |
| wide | 1280px | Full 12-column grid, hero at 60px on landing |
| max | 1440px | Container caps at 1200px, gutter expands |

### Touch targets

All interactive elements honour **44×44px minimum**. Primary CTAs at `10px 20px` padding render at ~40px tall — paired with extended tap padding via `::before` pseudo-element on mobile.

### Collapsing strategy

- **Hero** — single-column on mobile (copy → primary CTA → secondary CTA stacked).
- **Benchmark plot** — horizontal-bar chart stays horizontal at all sizes; bar labels reflow under bars on mobile.
- **Feature grid** — 3-up desktop → 2-up tablet → 1-up mobile.
- **Top nav** — links collapse into a hamburger drawer at <1024px; primary CTA stays visible.
- **Code samples** — desktop fits the full sample horizontally; mobile uses a horizontal scroll within the card.

### Image behaviour

- All product images SVG or AVIF with WebP fallback.
- `loading="lazy"` below the fold.
- `aspect-ratio` to prevent CLS.

### Container queries

Used on the benchmark card — at `@container (max-width: 480px)` the chart switches from horizontal-bar to a stacked label / value pair layout for mobile readability.

## 11. Content & Voice

### Tone

**Measured, factual, developer-direct.** You.com speaks the way a research-grade SaaS speaks to engineers — claims are quantified ("86% accuracy on SimpleQA"), the audience is assumed to be technical, and there is no consumer-marketing exuberance. The tone shares vocabulary with Stripe's developer pages and Vercel's framework documentation.

### Microcopy patterns

- **Button verbs** — "Get API key", "View docs", "Read benchmarks", "Talk to sales", "See pricing". Concrete actions, no abstract verbs.
- **Error messages** — `[Field/Operation]: [problem]. [Resolution].` Example: "API key: invalid. Generate a new key in your dashboard."
- **Success confirmations** — minimal: "API key copied", "Account created". No celebratory language.
- **Empty states** — "No requests yet. [Get started with the API →]"
- **Citation copy** — "Source: SimpleQA benchmark, May 2024". JetBrains Mono 11px, `#7c7d87`.

### CTA verb conventions

The brand uses **specific, technical** verbs:

1. **Get API key** — top hero CTA, the canonical conversion path.
2. **View docs** — secondary, for evaluators.
3. **Read benchmarks** — for proof-driven readers.
4. **Talk to sales** — for enterprise.
5. **See pricing** — for budget-driven evaluators.

Avoided: *Sign up* (too consumer), *Discover*, *Unlock*, *Get started* (too vague), *Try free* (too SaaS-template).

### Empty states

- Empty dashboard: "No API requests yet. [Read the quickstart →]"
- Empty benchmark filter: "No models match those filters. Try removing one filter."
- Empty search: "Nothing here yet. Try a different query."

### Tone anchors

- Cite. Every accuracy claim links to source.
- Quantify. "86%" beats "industry-leading".
- Use second person ("you", "your") sparingly — addresses the developer directly when discussing developer experience, but stays third-person when discussing data ("the model achieves 86%").
- Avoid superlatives. "Leading" is the strongest claim You.com makes about itself; "the best" is absent.
- Never apologise. There is no "We know AI is hard, but…" register.

## 12. Dark Mode & Theming

The marketing surface is **light-only** by design. The consumer search surface at `you.com/search` ships its own theming (with light + dark modes) but the developer-API marketing site holds light throughout.

If a dark mode were ever shipped for the marketing surface, it would need to:

- Swap canvas to `#0a0a14` (deep cool near-black with mild indigo undertone).
- Elevate text to `#f6f6f6` (matching the light-mode chip-grey but flipped for hierarchy).
- Drop the indigo saturation to `#7282f0` for body-level contrast on dark.
- Replace `#fafafa` benchmark ground with `#1a1b25`; competitor bar grey becomes `#3a3b45`.
- Keep indigo bar fill — the brand colour holds across modes.
- Replace `#121212` CTA with `#f6f6f6` CTA (inverts the chrome).

But none of this is shipped on the marketing surface. **Light-only — no dark variant offered for `you.com` marketing pages.**

## 13. Lineage & Influences

You.com's site documents the company's strategic pivot from consumer search engine to developer-grade web-data API. The visual language reflects that shift wholesale: where the consumer product (still live at `you.com/search`) leans on chatty hero surfaces and chip-led personalisation, the developer marketing page runs a measured-data register that quotes Vercel and Stripe in equal measure. Pure white canvas, custom **Lumen Sans** at 500 weight (a humanist face with mild contrast and slightly rounded terminals), 48px headlines with normal tracking, and near-black `#121212` rectangles for primary CTAs — none of which is novel on its own, but the *consistency* is the point.

The indigo accent `#5368ee` carries every benchmark bar and metric chip — it is the "data is the proof" brand colour, deployed only where accuracy claims are being made. Comparison surfaces use grey `#f6f6f6` chips at 4px radius (the densest, most spreadsheet-grade shape on the page). The lineage runs through Vercel's clean enterprise canvas, Stripe's data-as-marketing hero charts, and Mintlify's developer-doc neutrality. The most distinctive brand decision — keeping headline tracking at `normal` rather than the `-0.02em` default of every modern SaaS — places You.com slightly outside the Stripe/Linear cluster and closer to Notion's open headline cadence.

The brand also rejects two adjacent registers. You.com is *not* the consumer search register (no chip-led hero, no chat input, no citation cards on the landing page), and it is *not* the academic-paper register (no mono headlines, no preprint conventions). The market position — web search infrastructure for AI builders — demands the developer-doc-meets-data-publication register.

**Named influences**:
- **Vercel** ([https://vercel.com](https://vercel.com)) — White canvas, near-black rectangle CTAs, and developer-doc neutrality.
- **Stripe** ([https://stripe.com](https://stripe.com)) — Data-as-marketing — accuracy bars and benchmark plots as the centrepiece; single-confident-action discipline.
- **Mintlify** ([https://mintlify.com](https://mintlify.com)) — Developer-doc register and the discipline of small radii on data chips.
- **Linear** ([https://linear.app](https://linear.app)) — Custom-sans + restrained chromatic palette; though Linear runs warmer.
- **Notion** ([https://www.notion.com](https://www.notion.com)) — Open headline tracking; humanist sans cadence.
- **JetBrains Mono** ([https://www.jetbrains.com/mono/](https://www.jetbrains.com/mono/)) — Code sample type companion.
- **Tailwind UI / Headless UI** — The 8px button radius + 12px card radius vocabulary.

## 14. Do's and Don'ts

### Do

- **Reserve the indigo `#5368ee` for "our data".** Benchmark bars, key metric chips, the brand mark — and let competitor data sit in zinc grey.
- **Use Lumen Sans at 500 with normal tracking.** The open headline tone is part of the developer-doc register.
- **Keep CTAs as near-black rectangles at 8px.** Pill or rounded-soft buttons collapse the enterprise posture.
- **Use 4px radius on benchmark chips.** That density is the data-publication signature.
- **Show data as the hero**, not the headline. The benchmark plot lives near the top of the fold.
- **Cite every accuracy claim** with a JetBrains Mono 11px source caption.
- **Animate benchmark bars on scroll** (600ms ease-out fill). It's the page's signature moment.
- **Use the `#fafafa` plot backdrop** to define benchmark sections; let the plot bleed into the section bg.
- **Set focus ring as 2px `#5368ee` with 2px white offset.**
- **Honour `prefers-reduced-motion`** — disable benchmark bar fill animation entirely when set.

### Don't

- **Don't import the chatty hero language of `you.com/search` consumer surface.** The API marketing page is a different brand voice.
- **Don't drop shadows on benchmark plots.** Data should read as raw, not designed-on.
- **Don't introduce a second saturated colour.** The page is white, near-black, zinc, and one indigo — that discipline is the brand.
- **Don't compress headline tracking.** Lumen Sans holds at `tracking: normal`. `-0.02em` collapses you into the Stripe register.
- **Don't pill-radius buttons.** The 8px corner is essential.
- **Don't use indigo as a CTA fill.** Indigo signals proof, not action; near-black `#121212` is the action colour.
- **Don't show competitor bars in any colour other than `#d9d9df`.** Coloured competitor bars suggest equality — the chromatic split is doing the persuasion.
- **Don't use Inter or system-sans fallback first.** Lumen Sans is the brand; the fallback chain runs through Arial.
- **Don't increase chip radius above 4px.** The dense shape is the data-publication signal.
- **Don't write CTAs in marketing voice** ("Discover", "Unlock", "Sign up free"). Developer-direct verbs only.
- **Don't add a third action variant.** Primary near-black + secondary outlined + rare brand-indigo is the entire ladder.
- **Don't auto-play any video on the marketing page.** Static charts and code samples carry the demo.

## 15. Agent Prompt Guide

### Quick Color Reference

```
bg:                #ffffff
bg-soft:           #f6f6f6
surface-alt:       #fafafa
text:              #121212
text-muted:        #5e5f6b
brand:             #5368ee
brand-soft:        #e8ecff
cta-bg:            #121212
benchmark-our:     #5368ee
benchmark-them:    #d9d9df
border:            rgba(18, 18, 18, 0.10)
```

### Example Component Prompts

1. *"Create a You.com-style API hero: pure white canvas, headline 'The Leading Web Search APIs for AI' in Lumen Sans 500 / 48px / normal tracking / `#121212`. Lede in Lumen Sans 400 / 18px / 1.55 line-height / `#5e5f6b`, capped at 720px width. Primary CTA 'Get API key' as a `#121212` rectangle at 8px radius / 10px 20px padding / Lumen Sans 500 / 14px / `#ffffff` text. Secondary CTA 'View docs' as outlined `1px rgba(18, 18, 18, 0.18)` at the same 8px radius."*

2. *"Design a You.com-style benchmark plot: `#fafafa` bg / 12px radius / no border / 32px padding. Chart title 'SimpleQA Accuracy' in Lumen Sans 500 / 24px above. Horizontal bar chart with 4 rows. Top row 'You.com' uses `#5368ee` fill at 4px radius with white label '86%' inside the bar. Other rows use `#d9d9df` fill at 4px radius with `#5e5f6b` label. Source caption below in JetBrains Mono 11px / `#7c7d87`."*

3. *"Build a You.com-style API code sample card: `#fafafa` bg, 12px radius, `1px rgba(18, 18, 18, 0.06)` border, 20px padding. JetBrains Mono 13px / 1.55 line-height code with minimal syntax highlighting (keywords in `#5368ee`, strings in `#15803d`, comments in `#7c7d87`). Copy button at top-right — ghost style, transparent bg, hover `#f6f6f6`."*

4. *"Create a You.com-style feature card: `#ffffff` bg, 12px radius, `1px rgba(18, 18, 18, 0.10)` border, 24px padding, no shadow. Icon at top in `#5368ee` (SVG, 24px). Card title in Lumen Sans 500 / 18px / `#121212`. Description in Lumen Sans 400 / 15px / 1.5 line-height / `#5e5f6b`. Optional learn-more link at bottom in `#5368ee`."*

5. *"Build a You.com-style nav bar: 64px height, white bg, no border (until scroll). Wordmark left in Lumen Sans 600 / 18px. Nav links right at Lumen Sans 500 / 14px / `#121212`. Right cluster: 'Sign in' ghost button + 'Get API key' near-black rectangle at 8px radius."*

6. *"Design a You.com-style 3-up capability rail: 3-column grid on desktop (1200px container), 24px gutter. Above the rail: section eyebrow 'Capabilities' in Lumen Sans 500 / 12px uppercase / 0.06em tracking / `#5e5f6b`, then heading 'Built for AI builders' in Lumen Sans 500 / 30px / `#121212`. Each cell is a feature card."*

### Iteration Guide

1. **Verify headline tracking is `normal`, not `-0.02em`.** Lumen Sans's open headline cadence is the brand's most distinctive typographic move.
2. **Audit indigo usage — it's "our data", never CTA fill.** If you find an indigo button on the page, it should be the rare brand-CTA exception (max 1 per page).
3. **Check benchmark chip radius is 4px.** Larger radii collapse the data-publication register.
4. **Confirm `#d9d9df` for competitor bars, never coloured.** The chromatic split is the persuasion.
5. **Verify CTA copy uses developer-direct verbs** ("Get API key", "View docs"). Replace any consumer-SaaS verbs.
6. **Add `tnum` to all benchmark numerals.** Tabular alignment is mandatory.
7. **Strip any drop shadows from cards and benchmark plots.** Hairline borders only.
8. **Ensure benchmark bar fill animation is `ease-out` over 600ms** — and disabled under `prefers-reduced-motion`.
Prose

1. Visual Theme & Atmosphere

You.com’s marketing surface stages the company as web-data infrastructure for AI builders. The hero — “The Leading Web Search APIs for AI” — sits in custom Lumen Sans at 48px / 500 weight on pure white, with a measured benchmark plot below the fold showing SimpleQA and FRAMES accuracy. The indigo #5368ee brand accent fills the You.com bars; competitor bars get a neutral #d9d9df grey. That single chromatic decision — saturated indigo for our data, neutral grey for theirs — does most of the persuasive work on the page.

The visual register is measured-data publication. Lumen Sans (a humanist face with mild contrast and slightly rounded terminals, custom-designed for the company) reads as Inter’s calmer cousin — open headlines, no negative tracking, generous body line-height. Where Stripe compresses headlines, where Linear tightens tracking, where Vercel goes near-Inter, You.com leaves headlines open. The lack of negative tracking is itself a brand choice: the type breathes, and the breath signals “we’re confident in our numbers, we don’t need typographic compression to demand attention.”

The chromatic palette is narrow by design. White, near-black #121212, neutral grey #f6f6f6, and one saturated indigo #5368ee. The indigo never appears as a CTA fill (those are near-black rectangles); it appears as the colour of proof — benchmark bars, accuracy chips, citation links. The “our data is indigo, their data is grey” pattern propagates throughout the site.

The 4px benchmark-chip radius is the densest, most spreadsheet-grade shape on the page — most modern sites land at 6–8px minimum on chips. The 4px choice signals “this is data, not decoration.” Cards round at 12px, buttons at 8px — both standard, neither expressive. The shape vocabulary is conservative on purpose; the data is the protagonist.

Atmospheric vocabulary: developer-doc-white, Lumen-open, indigo-proof, near-black-rectangle-CTA, accuracy-bar, benchmark-publication, Vercel-cousin-Mintlify-cousin, search-as-infrastructure, our-data-vs-theirs.

Key Characteristics

  • Pure white #ffffff developer-doc canvas
  • Custom Lumen Sans at weight 500 with normal tracking (open, not compressed)
  • Saturated indigo #5368ee reserved for “our data” — never a CTA fill
  • Near-black #121212 rectangle CTAs at 8px radius
  • 4px benchmark chip radius — densest shape on the page
  • #fafafa plot backdrop with #5368ee + #d9d9df bar pair
  • 12px cards with hairline borders — flat, no shadow
  • Single-family type system (Lumen Sans + JetBrains Mono companion)
  • 720px hero prose width — broadsheet narrow on a 1200px page
  • Data-first hierarchy — the benchmark plot is the hero, not the headline

2. Color Palette & Roles

Primary

  • bg #ffffff — pure white developer-doc canvas, the defining surface.
  • text #121212 — near-black body text; warmer than pure #000.
  • bg-soft #f6f6f6 — competitor-bar grey on benchmark plots; also used for code-sample plates.
  • surface-alt #fafafa — benchmark plot backdrop; one notch lighter than #f6f6f6.
  • cta-bg #121212 — primary CTA near-black rectangle.
  • on-cta #ffffff — white label on near-black.

Brand & Accent (indigo)

  • brand #5368ee — signature indigo; benchmark bars, link colour, brand mark.
  • brand-hover #3a4ec8 — darker pressed indigo for buttons and links.
  • brand-deep #293b9a — deepest accent on white (badge text, emphasis).
  • brand-soft #e8ecff — info surface tint, status pill bg.
  • brand-faint #f4f6ff — quietest indigo tint, used as section background in rare promotional bands.
  • brand-glow rgba(83, 104, 238, 0.20) — focus glow effect.

Interactive

  • link #5368ee — saturated indigo, underline on hover.
  • link-hover #3a4ec8 — pressed state.
  • selected-bg #e8ecff — selected nav item, selected row in spec tables.
  • disabled-bg #f6f6f6 — disabled fill.
  • disabled-text #a8a9b1 — disabled label.
  • focus-ring #5368ee — 2px solid with 2px white offset.

Neutral Scale

  • near-black #121212 — primary text.
  • slate-medium #2a2b35 — secondary heading emphasis.
  • slate-muted #5e5f6b — secondary copy, the most-used muted tone.
  • slate-soft #7c7d87 — supporting copy.
  • slate-faint #a8a9b1 — disabled, microcopy.
  • slate-line #d9d9df — competitor bar fill (also a strong divider).

Surface & Borders

  • surface-0 (page)#ffffff pure white.
  • surface-1 (panel)#fafafa benchmark plot backdrop.
  • surface-2 (chip-grey)#f6f6f6 for code samples and competitor data.
  • surface-3 (hover)#f8f8f8 interactive hover state.
  • border rgba(18, 18, 18, 0.10) — default hairline.
  • border-strong rgba(18, 18, 18, 0.18) — emphasized rule, used on button-secondary.
  • border-soft rgba(18, 18, 18, 0.06) — quietest division.

Shadow Colors

You.com is flat-first. Marketing surface uses tonal layering and hairline borders for 95% of depth. The single place a real shadow appears is the navigation dropdown (rgba(18, 18, 18, 0.10) 0 16px 32px -12px) and the rare modal. Shadows are near-black tinted, never indigo-tinted.

Semantic

  • success#dcfce7 / #15803d. Used for “API key generated”, “Account active”.
  • warning#fef3c7 / #854d0e. Used for rate-limit warnings.
  • danger#fee2e2 / #b91c1c. Used for failed requests, account issues.
  • info#e8ecff / #293b9a. Reuses brand-indigo pair; signals “You.com info” tone.

Benchmark-specific

The chart pair is doctrinal:

  • benchmark-our #5368ee — saturated indigo, “our number”.
  • benchmark-them #d9d9df — neutral grey, “their number”. Slightly darker than #f6f6f6 to remain visible on #fafafa plot ground.
  • benchmark-ground #fafafa — plot backdrop.
  • benchmark-axis rgba(18, 18, 18, 0.12) — axis lines, gridlines.

3. Typography Rules

Font Family

  • Display & Body: Lumen Sans, a custom humanist sans with mild contrast and modestly rounded terminals. Loaded with weights 400 / 500 / 600. Lumen reads as Inter’s calmer, more-rounded cousin — slightly warmer, slightly more open. Fallback chain: Arial → ui-sans-serif → system-ui → sans-serif.
  • Mono: JetBrains Mono for code samples and rare benchmark numerals. Fallback to ui-monospace, "SF Mono", Menlo, Consolas, monospace.
  • OpenType features: kern always; ss01 on display headlines (cleaner alt-glyphs); tnum + zero mandatory on mono for legible numerics in code samples.

Hierarchy

RoleFontSizeWeightLine HeightLetter SpacingOT FeaturesNotes
display-heroLumen Sans725001.05normalss01Rare hero — major page openers
displayLumen Sans605001.08normalSection openers
h1Lumen Sans485001.1normalStandard hero (“The Leading Web Search APIs for AI”)
h2Lumen Sans305001.2normalSection heading
h3Lumen Sans245001.3normalSubsection
h4Lumen Sans185001.4normalCard heading
h5Lumen Sans165001.4normalInline heading
eyebrowLumen Sans125001.40.06emuppercaseSection label
body-largeLumen Sans184001.55normalLede
bodyLumen Sans164001.5normalDefault body
body-smallLumen Sans144001.5normalSecondary copy
captionLumen Sans134001.4normalHelper text
caption-tabularJetBrains Mono135001.4normaltnumSpec-row data
labelLumen Sans125001.3normalForm labels, tags
label-ctaLumen Sans145001.2normalButton text
codeJetBrains Mono134001.55normaltnum zeroAPI code samples
code-microJetBrains Mono114001.4normalFootnote, citation
benchmarkJetBrains Mono135001.3normaltnumAccuracy values, chart labels

Principles

  • Normal tracking on display. Lumen Sans headlines hold at tracking: normal — no -0.02em compression. The open headline tone is the brand’s most distinctive typographic move.
  • 500 is the heading weight. Never 600 or 700 on display; never 400 on h1-h3. The single weight stripe gives the page a calm authority.
  • Single-family type system. No serif counterpoint, no editorial italic. Lumen Sans + JetBrains Mono is the entire vocabulary.
  • Body line-height of 1.5–1.55. Slightly more leading than developer-doc default (1.4–1.5). Reads as comfortable rather than dense.
  • Mono for code only — and benchmark labels. JetBrains Mono surfaces only inside code samples or chart-axis labels. The marketing prose stays sans throughout.
  • Numbers in mono with tnum. Tabular numerals are mandatory on benchmark values and code samples — every chart aligns numerically.
  • No italic body emphasis. Use weight 500 on body for emphasis; italic is reserved for citation captions.

4. Component Stylings

Buttons

Primary (near-black rectangle)#121212 bg, #ffffff text, 8px radius, Lumen Sans 500 / 14px, padding 10px 20px. Hover lifts to #2a2b35; active drops to #000. Used for: “Get API key”, “Talk to sales”, “Create account”.

Secondary (outlined rectangle)#ffffff bg, #121212 text, 1px rgba(18, 18, 18, 0.18) border, 8px radius, identical typography to primary. Hover wash #f8f8f8. Used for: “View docs”, “Read benchmarks”, “Contact us”.

Indigo (brand CTA)#5368ee bg, #ffffff text, 8px radius. Hover #3a4ec8. Reserved for the rare brand-hero CTA — appears at most once per page, signals “try our data” path.

Ghost — transparent, #121212 text, 6px radius, 8px 12px padding. Hover wash #f6f6f6. Used for nav links, inline actions.

Cards

Feature card#ffffff bg, 1px rgba(18, 18, 18, 0.10) border, 12px radius, 24px padding, no shadow. Used for capability tiles, doc links, pricing tiers.

Code sample card#fafafa bg, 1px rgba(18, 18, 18, 0.06) border, 12px radius, 20px padding. JetBrains Mono content inside. Copy button at top-right.

Benchmark card#fafafa bg, no border, 12px radius, 32px padding. Contains a single horizontal-bar chart with You.com indigo + competitor grey bars.

Badges, Tags, Pills

Benchmark chip (indigo)#5368ee bg, #ffffff text, Lumen Sans 500 / 12px, 4px radius. The signature data shape — used on bar segments and key-metric chips.

Benchmark chip (grey)#d9d9df bg, #5e5f6b text, same typography, 4px radius. The competitor counterpart.

Status pill (indigo soft)#e8ecff bg, #293b9a text, Lumen Sans 500 / 12px, pill radius (9999). Used for nav Beta, New, Live indicators.

Inputs & Forms

Default input#ffffff bg, 1px rgba(18, 18, 18, 0.18) border, 8px radius, 10px 14px padding, Lumen Sans 400 / 16px, #a8a9b1 placeholder. Focus ring 0 0 0 2px #5368ee with 2px white offset.

Form labels — Lumen Sans 500 / 14px, #121212, 4px margin-bottom from input.

Helper text — Lumen Sans 400 / 13px, #5e5f6b, 4px margin-top from input.

Error state — border #fee2e2; helper text flips to #b91c1c.

Top nav — 64px header height, #ffffff bg with 1px rgba(18, 18, 18, 0.06) bottom border (only on scroll), Lumen Sans 500 / 14px / #121212 links. Hover lightens to #5e5f6b. Right cluster: “Sign in” ghost link + “Get API key” near-black rectangle CTA.

Footer nav — Lumen Sans 400 / 14px / #5e5f6b, 4-column grid on desktop.

Benchmark Plot (the signature module)

Chart container#fafafa bg, no border, 12px radius, 32px padding. Chart title in Lumen Sans 500 / 24px above. Source caption in JetBrains Mono 11px / #7c7d87 below.

Bar (our)#5368ee fill, 4px radius, height ~24px. Bar label inside-end if fits, else outside-end. Label in Lumen Sans 500 / 13px / #ffffff (inside) or #121212 (outside).

Bar (their)#d9d9df fill, 4px radius, same height. Label #5e5f6b.

Axisrgba(18, 18, 18, 0.12) line, JetBrains Mono 11px tick labels.

Tooltips

Tooltip#121212 bg, #ffffff text, 6px radius, Lumen Sans 400 / 13px, 8px 12px padding, 200ms fade.

Toasts

Toast#ffffff bg, 1px rgba(18, 18, 18, 0.10) border, 8px radius, ambient shadow, 12px 16px padding. Slides up from bottom-right.

Modals

Modal#ffffff panel, 12px radius, modal shadow, 40px padding. Backdrop rgba(18, 18, 18, 0.5).

5. Layout Principles

Spacing System

Base unit 4px. Scale: 1, 2, 4, 6, 8, 10, 12, 16, 20, 24, 32, 48, 64, 80, 96, 128. Component padding lives in 8–24; section padding 80–128. The system reads as developer-doc dense — slightly tighter than Anthropic, slightly looser than Stripe.

Grid & Container

  • Page max-width: 1200px, centred, clamp(24px, 5vw, 64px) site gutter.
  • Hero prose-width: 720px max — broadsheet narrow.
  • Grid columns: 12, 24px gutter.
  • Feature grid: 3-up cards on desktop with equal-width columns.
  • Benchmark plot: full-width within container.

Whitespace Philosophy

Between sections: 80–128px on desktop, 48px on mobile. Within sections: 24–48px between groups. The page is organised as hero + benchmark plot + accuracy claim + 3-up capability rail + API code sample + pricing/contact. The benchmark plot lives near the top of the fold — it’s the proof, not the conclusion.

Section Cadence

The page alternates white and #fafafa faint-grey bands every 2–3 sections. The benchmark plot uses the #fafafa band so the chart’s plot backdrop continues seamlessly into the section. There is no dark-mode brand band — light throughout.

6. Shapes & Radius Scale

TierValueUse
Micro2pxHairline indicators, focus inner-stroke
Small4pxBenchmark chips, bar segments — the signature dense shape
Medium6pxGhost buttons, dropdown items
Standard8pxButtons (primary, secondary, indigo), inputs
Card12pxFeature cards, code sample cards, benchmark plot container
Featured16pxReserved (rare hero modules)
Pill9999pxStatus pills, nav badges

The 4px benchmark-chip radius is the densest shape on the page and the most distinctive — most modern sites land at 6–8px minimum on chips and pills. The tighter radius signals “data, not decoration.” Cards hold at 12px (matching Stripe and Notion); buttons at 8px (matching Vercel and Linear).

7. Depth & Elevation

LevelTreatmentUse
0 (flat)No shadow, no borderPage bg, hero copy
1 (hairline)1px rgba(18, 18, 18, 0.10) borderDefault cards
2 (tonal)#fafafa bg tint, no shadowCode panels, benchmark plot section
3 (ambient)rgba(18, 18, 18, 0.04) 0 1px 3pxToast, light hover
4 (dropdown)rgba(18, 18, 18, 0.10) 0 16px 32px -12pxNav dropdown menu
5 (modal)rgba(18, 18, 18, 0.16) 0 24px 48px -12pxModal panel

Shadow Philosophy

You.com is flat-first, like Cartesia and Vercel. Marketing surface depth comes from tonal layering plus hairline borders. The benchmark plot — the most data-dense module — has no border, no shadow; it relies on the #fafafa plot ground to define its boundaries against the white page. Real shadows live only on dropdowns and modals, both near-black tinted at low opacity. The indigo brand accent never appears in shadow — it’s reserved for fill and focus-ring.

8. Interaction & Motion

Easing curves

  • Standardcubic-bezier(0.4, 0, 0.2, 1) — default for hover, focus.
  • Emphasizedcubic-bezier(0.2, 0, 0, 1) — incoming elements, modals.
  • Outcubic-bezier(0.16, 1, 0.3, 1) — overshoot-free decelerate for benchmark-bar fill animations.

Duration buckets

  • Instant — 80ms — focus ring, micro-state.
  • Fast — 120ms — hover bg shift.
  • Standard — 200ms — default transitions.
  • Slow — 320ms — modal opens, dropdowns.
  • Page — 400ms — route transitions.
  • Bar — 600ms — benchmark bar fill animation (the signature page-scroll moment).

Per-component micro-states

  • Button hover — bg shifts via 120ms ease-standard. No translate, no scale.
  • Card hover — border-soft brightens from rgba(18, 18, 18, 0.10) to rgba(18, 18, 18, 0.18) over 200ms.
  • Link hover — colour stays indigo, underline reveals via text-decoration over 120ms.
  • Input focus — focus-ring fades in 80ms; border swaps to #5368ee.
  • Benchmark bar fill — bars animate width 0 → final over 600ms ease-out when scrolled into view via IntersectionObserver. This is the page’s signature moment — the data resolves before the user’s eyes.
  • Toast — slides up 8px and fades 0 → 1 over 320ms.
  • Modal — backdrop fades 0 → 0.5 over 200ms; panel scales 0.98 → 1 simultaneously.

Page transitions

Marketing pages use SPA-style transitions with 400ms ease-standard fade-through. Section anchors use scroll-behavior: smooth.

Reduced-motion strategy

prefers-reduced-motion: reduce is fully honoured. The benchmark bar fill animation disables entirely — bars render at final width with no animation (this is the most consequential reduced-motion override). Translate transforms become opacity fades. Smooth scroll disables.

9. Accessibility & A11y

Contrast pairs (computed)

PairRatioWCAG
#121212 on #ffffff (body)17.4:1AAA
#ffffff on #121212 (CTA)17.4:1AAA
#5e5f6b on #ffffff (muted)6.2:1AAA
#5368ee on #ffffff (link / indigo CTA)4.7:1AA at body
#ffffff on #5368ee (indigo bar label)4.7:1AA at body
#293b9a on #e8ecff (badge)7.5:1AAA
#5e5f6b on #d9d9df (competitor bar label)5.6:1AA

Focus indicators

2px solid #5368ee with 2px white offset on every interactive surface. Inputs additionally swap their border to #5368ee on focus. The indigo focus is visually distinct from any neutral UI colour.

ARIA patterns

  • Benchmark chart — wraps a properly-marked-up <table> for screen readers (rows: model name, accuracy, p-value); the visual chart is role="img" + aria-label="Benchmark chart: You.com 86% accuracy on SimpleQA versus competitors at 78%, 71%, 65%". Keyboard users tab into the table; visual users see the chart.
  • Comboboxrole="combobox" + aria-controls + aria-expanded + aria-activedescendant.
  • Modalrole="dialog" + aria-modal="true" + aria-labelledby + aria-describedby. Initial focus on first input; ESC dismisses.
  • Tooltiprole="tooltip" + aria-describedby from trigger.
  • Tabsrole="tablist" + role="tab" + aria-selected + arrow-key navigation.

Keyboard navigation

  • Tab order matches reading order — header, hero CTA, benchmark plot (skipped, links to data table), feature cards, footer.
  • ESC closes modals, dropdowns.
  • Arrow keys move within tab-lists, dropdowns, comboboxes.
  • Skip-to-content link on first Tab.

Screen reader hints

  • Benchmark chart announces full data via the adjacent <table> markup; users hear “You.com: 86 percent accuracy. Competitor A: 78 percent…”
  • The 4px-radius benchmark chip uses aria-label describing the metric (“Indigo chip indicating You.com’s 86% accuracy on SimpleQA”).
  • All decorative SVG illustrations are aria-hidden="true".
  • Code samples wrap in <pre><code> with aria-label="Python example using You.com Search API".

Reduced motion

Honoured globally. The benchmark bar fill animation is the most affected — bars render at final width with no animation when prefers-reduced-motion: reduce is set.

10. Responsive Behavior

Breakpoints

NameMin-widthNotes
mobile0Single column, 24px gutter, hero at 32px
tablet640px2-up feature grid, hero at 36px
desktop1024px3-up grid, hero at 48px
wide1280pxFull 12-column grid, hero at 60px on landing
max1440pxContainer caps at 1200px, gutter expands

Touch targets

All interactive elements honour 44×44px minimum. Primary CTAs at 10px 20px padding render at ~40px tall — paired with extended tap padding via ::before pseudo-element on mobile.

Collapsing strategy

  • Hero — single-column on mobile (copy → primary CTA → secondary CTA stacked).
  • Benchmark plot — horizontal-bar chart stays horizontal at all sizes; bar labels reflow under bars on mobile.
  • Feature grid — 3-up desktop → 2-up tablet → 1-up mobile.
  • Top nav — links collapse into a hamburger drawer at <1024px; primary CTA stays visible.
  • Code samples — desktop fits the full sample horizontally; mobile uses a horizontal scroll within the card.

Image behaviour

  • All product images SVG or AVIF with WebP fallback.
  • loading="lazy" below the fold.
  • aspect-ratio to prevent CLS.

Container queries

Used on the benchmark card — at @container (max-width: 480px) the chart switches from horizontal-bar to a stacked label / value pair layout for mobile readability.

11. Content & Voice

Tone

Measured, factual, developer-direct. You.com speaks the way a research-grade SaaS speaks to engineers — claims are quantified (“86% accuracy on SimpleQA”), the audience is assumed to be technical, and there is no consumer-marketing exuberance. The tone shares vocabulary with Stripe’s developer pages and Vercel’s framework documentation.

Microcopy patterns

  • Button verbs — “Get API key”, “View docs”, “Read benchmarks”, “Talk to sales”, “See pricing”. Concrete actions, no abstract verbs.
  • Error messages[Field/Operation]: [problem]. [Resolution]. Example: “API key: invalid. Generate a new key in your dashboard.”
  • Success confirmations — minimal: “API key copied”, “Account created”. No celebratory language.
  • Empty states — “No requests yet. [Get started with the API →]”
  • Citation copy — “Source: SimpleQA benchmark, May 2024”. JetBrains Mono 11px, #7c7d87.

CTA verb conventions

The brand uses specific, technical verbs:

  1. Get API key — top hero CTA, the canonical conversion path.
  2. View docs — secondary, for evaluators.
  3. Read benchmarks — for proof-driven readers.
  4. Talk to sales — for enterprise.
  5. See pricing — for budget-driven evaluators.

Avoided: Sign up (too consumer), Discover, Unlock, Get started (too vague), Try free (too SaaS-template).

Empty states

  • Empty dashboard: “No API requests yet. [Read the quickstart →]”
  • Empty benchmark filter: “No models match those filters. Try removing one filter.”
  • Empty search: “Nothing here yet. Try a different query.”

Tone anchors

  • Cite. Every accuracy claim links to source.
  • Quantify. “86%” beats “industry-leading”.
  • Use second person (“you”, “your”) sparingly — addresses the developer directly when discussing developer experience, but stays third-person when discussing data (“the model achieves 86%”).
  • Avoid superlatives. “Leading” is the strongest claim You.com makes about itself; “the best” is absent.
  • Never apologise. There is no “We know AI is hard, but…” register.

12. Dark Mode & Theming

The marketing surface is light-only by design. The consumer search surface at you.com/search ships its own theming (with light + dark modes) but the developer-API marketing site holds light throughout.

If a dark mode were ever shipped for the marketing surface, it would need to:

  • Swap canvas to #0a0a14 (deep cool near-black with mild indigo undertone).
  • Elevate text to #f6f6f6 (matching the light-mode chip-grey but flipped for hierarchy).
  • Drop the indigo saturation to #7282f0 for body-level contrast on dark.
  • Replace #fafafa benchmark ground with #1a1b25; competitor bar grey becomes #3a3b45.
  • Keep indigo bar fill — the brand colour holds across modes.
  • Replace #121212 CTA with #f6f6f6 CTA (inverts the chrome).

But none of this is shipped on the marketing surface. Light-only — no dark variant offered for you.com marketing pages.

13. Lineage & Influences

You.com’s site documents the company’s strategic pivot from consumer search engine to developer-grade web-data API. The visual language reflects that shift wholesale: where the consumer product (still live at you.com/search) leans on chatty hero surfaces and chip-led personalisation, the developer marketing page runs a measured-data register that quotes Vercel and Stripe in equal measure. Pure white canvas, custom Lumen Sans at 500 weight (a humanist face with mild contrast and slightly rounded terminals), 48px headlines with normal tracking, and near-black #121212 rectangles for primary CTAs — none of which is novel on its own, but the consistency is the point.

The indigo accent #5368ee carries every benchmark bar and metric chip — it is the “data is the proof” brand colour, deployed only where accuracy claims are being made. Comparison surfaces use grey #f6f6f6 chips at 4px radius (the densest, most spreadsheet-grade shape on the page). The lineage runs through Vercel’s clean enterprise canvas, Stripe’s data-as-marketing hero charts, and Mintlify’s developer-doc neutrality. The most distinctive brand decision — keeping headline tracking at normal rather than the -0.02em default of every modern SaaS — places You.com slightly outside the Stripe/Linear cluster and closer to Notion’s open headline cadence.

The brand also rejects two adjacent registers. You.com is not the consumer search register (no chip-led hero, no chat input, no citation cards on the landing page), and it is not the academic-paper register (no mono headlines, no preprint conventions). The market position — web search infrastructure for AI builders — demands the developer-doc-meets-data-publication register.

Named influences:

  • Vercel (https://vercel.com) — White canvas, near-black rectangle CTAs, and developer-doc neutrality.
  • Stripe (https://stripe.com) — Data-as-marketing — accuracy bars and benchmark plots as the centrepiece; single-confident-action discipline.
  • Mintlify (https://mintlify.com) — Developer-doc register and the discipline of small radii on data chips.
  • Linear (https://linear.app) — Custom-sans + restrained chromatic palette; though Linear runs warmer.
  • Notion (https://www.notion.com) — Open headline tracking; humanist sans cadence.
  • JetBrains Mono (https://www.jetbrains.com/mono/) — Code sample type companion.
  • Tailwind UI / Headless UI — The 8px button radius + 12px card radius vocabulary.

14. Do’s and Don’ts

Do

  • Reserve the indigo #5368ee for “our data”. Benchmark bars, key metric chips, the brand mark — and let competitor data sit in zinc grey.
  • Use Lumen Sans at 500 with normal tracking. The open headline tone is part of the developer-doc register.
  • Keep CTAs as near-black rectangles at 8px. Pill or rounded-soft buttons collapse the enterprise posture.
  • Use 4px radius on benchmark chips. That density is the data-publication signature.
  • Show data as the hero, not the headline. The benchmark plot lives near the top of the fold.
  • Cite every accuracy claim with a JetBrains Mono 11px source caption.
  • Animate benchmark bars on scroll (600ms ease-out fill). It’s the page’s signature moment.
  • Use the #fafafa plot backdrop to define benchmark sections; let the plot bleed into the section bg.
  • Set focus ring as 2px #5368ee with 2px white offset.
  • Honour prefers-reduced-motion — disable benchmark bar fill animation entirely when set.

Don’t

  • Don’t import the chatty hero language of you.com/search consumer surface. The API marketing page is a different brand voice.
  • Don’t drop shadows on benchmark plots. Data should read as raw, not designed-on.
  • Don’t introduce a second saturated colour. The page is white, near-black, zinc, and one indigo — that discipline is the brand.
  • Don’t compress headline tracking. Lumen Sans holds at tracking: normal. -0.02em collapses you into the Stripe register.
  • Don’t pill-radius buttons. The 8px corner is essential.
  • Don’t use indigo as a CTA fill. Indigo signals proof, not action; near-black #121212 is the action colour.
  • Don’t show competitor bars in any colour other than #d9d9df. Coloured competitor bars suggest equality — the chromatic split is doing the persuasion.
  • Don’t use Inter or system-sans fallback first. Lumen Sans is the brand; the fallback chain runs through Arial.
  • Don’t increase chip radius above 4px. The dense shape is the data-publication signal.
  • Don’t write CTAs in marketing voice (“Discover”, “Unlock”, “Sign up free”). Developer-direct verbs only.
  • Don’t add a third action variant. Primary near-black + secondary outlined + rare brand-indigo is the entire ladder.
  • Don’t auto-play any video on the marketing page. Static charts and code samples carry the demo.

15. Agent Prompt Guide

Quick Color Reference

bg:                #ffffff
bg-soft:           #f6f6f6
surface-alt:       #fafafa
text:              #121212
text-muted:        #5e5f6b
brand:             #5368ee
brand-soft:        #e8ecff
cta-bg:            #121212
benchmark-our:     #5368ee
benchmark-them:    #d9d9df
border:            rgba(18, 18, 18, 0.10)

Example Component Prompts

  1. “Create a You.com-style API hero: pure white canvas, headline ‘The Leading Web Search APIs for AI’ in Lumen Sans 500 / 48px / normal tracking / #121212. Lede in Lumen Sans 400 / 18px / 1.55 line-height / #5e5f6b, capped at 720px width. Primary CTA ‘Get API key’ as a #121212 rectangle at 8px radius / 10px 20px padding / Lumen Sans 500 / 14px / #ffffff text. Secondary CTA ‘View docs’ as outlined 1px rgba(18, 18, 18, 0.18) at the same 8px radius.”

  2. “Design a You.com-style benchmark plot: #fafafa bg / 12px radius / no border / 32px padding. Chart title ‘SimpleQA Accuracy’ in Lumen Sans 500 / 24px above. Horizontal bar chart with 4 rows. Top row ‘You.com’ uses #5368ee fill at 4px radius with white label ‘86%’ inside the bar. Other rows use #d9d9df fill at 4px radius with #5e5f6b label. Source caption below in JetBrains Mono 11px / #7c7d87.”

  3. “Build a You.com-style API code sample card: #fafafa bg, 12px radius, 1px rgba(18, 18, 18, 0.06) border, 20px padding. JetBrains Mono 13px / 1.55 line-height code with minimal syntax highlighting (keywords in #5368ee, strings in #15803d, comments in #7c7d87). Copy button at top-right — ghost style, transparent bg, hover #f6f6f6.”

  4. “Create a You.com-style feature card: #ffffff bg, 12px radius, 1px rgba(18, 18, 18, 0.10) border, 24px padding, no shadow. Icon at top in #5368ee (SVG, 24px). Card title in Lumen Sans 500 / 18px / #121212. Description in Lumen Sans 400 / 15px / 1.5 line-height / #5e5f6b. Optional learn-more link at bottom in #5368ee.”

  5. “Build a You.com-style nav bar: 64px height, white bg, no border (until scroll). Wordmark left in Lumen Sans 600 / 18px. Nav links right at Lumen Sans 500 / 14px / #121212. Right cluster: ‘Sign in’ ghost button + ‘Get API key’ near-black rectangle at 8px radius.”

  6. “Design a You.com-style 3-up capability rail: 3-column grid on desktop (1200px container), 24px gutter. Above the rail: section eyebrow ‘Capabilities’ in Lumen Sans 500 / 12px uppercase / 0.06em tracking / #5e5f6b, then heading ‘Built for AI builders’ in Lumen Sans 500 / 30px / #121212. Each cell is a feature card.”

Iteration Guide

  1. Verify headline tracking is normal, not -0.02em. Lumen Sans’s open headline cadence is the brand’s most distinctive typographic move.
  2. Audit indigo usage — it’s “our data”, never CTA fill. If you find an indigo button on the page, it should be the rare brand-CTA exception (max 1 per page).
  3. Check benchmark chip radius is 4px. Larger radii collapse the data-publication register.
  4. Confirm #d9d9df for competitor bars, never coloured. The chromatic split is the persuasion.
  5. Verify CTA copy uses developer-direct verbs (“Get API key”, “View docs”). Replace any consumer-SaaS verbs.
  6. Add tnum to all benchmark numerals. Tabular alignment is mandatory.
  7. Strip any drop shadows from cards and benchmark plots. Hairline borders only.
  8. Ensure benchmark bar fill animation is ease-out over 600ms — and disabled under prefers-reduced-motion.
Ship with this

Drop you-com into your project, then ship the actual sections in an afternoon.

1 · install design
npx design-md add you-com
2 · ship landing page
npx agentkit init --design you-com
How AgentKit reads DESIGN.md
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