--- version: alpha name: anthropic.com description: "Light product system built on #faf9f5 with #141413 as the primary CTA accent. Type anchored in Anthropic Serif at 68.3429px / weight 400. Extracted automatically from https://anthropic.com/ — rendered styles via getComputedStyle() + CSS custom properties (token-only values may not be painted)." narrative: | anthropic.com is built on a warm, off-white canvas (rgb(250, 249, 245)). The system uses rgb(20, 20, 19) as a near-neutral accent (low saturation). Sharp 0px corners on CTAs — architectural restraint, engineering precision alongside editorial serif type (Anthropic Serif) — voice of authority. Anthropic Serif is paired with Anthropic Sans for secondary roles. A restrained elevation system (1 distinct shadow) — shadows reserved for the few elements that must lift off the page. Motion is a first-class concern — 5 keyframe animations plus transition-driven interactions. colors: background: "#faf9f5" surface-1: "#f0eee6" surface-2: "#f9f9f7" ink: "#141413" ink-muted: "rgba(20, 20, 19, 0.65)" ink-subtle: "#141413" primary: "#141413" on-primary: "#ffffff" primary-hover: "#3d3d3a" hairline: "rgba(20, 20, 19, 0.1)" typography: display-xl: fontFamily: "Anthropic Serif, Georgia, 'Times New Roman', serif" fontSize: 68.3429px fontWeight: 400 lineHeight: 1.1 letterSpacing: 0 display-md: fontFamily: "Anthropic Sans, 'SF Pro Display', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif" fontSize: 24px fontWeight: 600 lineHeight: 1.3 letterSpacing: 0 body: fontFamily: "Anthropic Serif, Georgia, 'Times New Roman', serif" fontSize: 20px fontWeight: 400 lineHeight: 1.4 letterSpacing: 0 body-sm: fontFamily: "Anthropic Serif, Georgia, 'Times New Roman', serif" fontSize: 18px fontWeight: 600 lineHeight: 1.4 letterSpacing: 0 caption: fontFamily: "Anthropic Sans, 'SF Pro Display', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif" fontSize: 16px fontWeight: 500 lineHeight: 1.4 letterSpacing: 0 button: fontFamily: "Anthropic Sans, 'SF Pro Display', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif" fontSize: 16px fontWeight: 400 lineHeight: 1 letterSpacing: -0.08px rounded: none: 0px xs: 8px sm: 16px md: 24px lg: 1600px xl: 1608px pill: 1600px spacing: xxs: 2px xs: 4px sm: 8px md: 12px lg: 24px xl: 32px xxl: 64px components: button-ghost: backgroundColor: "transparent" textColor: "{colors.hairline}" typography: "{typography.body}" rounded: "{rounded.none}" padding: 22.4px 12px button-ghost-2: backgroundColor: "transparent" textColor: "{colors.hairline}" typography: "{typography.body}" rounded: "{rounded.none}" padding: 0px 0px 0px 12px button-dark--solid: backgroundColor: "{colors.hairline}" textColor: "{colors.background}" typography: "{typography.button}" rounded: "{rounded.xs}" padding: 8px 16px extracted_at: "2026-06-11T06:01:23.750Z" completeness: 68 scoreVersion: "v2" --- # Design System — anthropic.com > Extracted automatically by Prism from https://anthropic.com > Date: 2026-06-11 > Viewport: Desktop 1440x900 + Mobile 390x844 > Values are extracted, not hand-written: rendered styles via getComputedStyle() + colors declared in CSS custom properties (token-only values are marked `(token)` and may not be painted). ## 0. Design DNA **Density**: moderate  |  **Motion**: subtle  |  **Weight**: heavy  |  **Aesthetic**: editorial-minimal | Dimension | Value | Signal | |---|---|---| | Canvas | neutral | `#faf9f5` | | Type posture | serif-led (Anthropic Serif) | "Announcing Fable 5" | | Color assertion | dual-accent | #141413 | | Whitespace | moderate | section rhythm 48px | | Interaction | subtle | 5 keyframes, 20 transitions | | Radius language | 8px-rounded | from token scale | **Prism fingerprint**: `neutral-canvas · serif-display · dual-accent · 8px-rounded · subtle-motion` > **🤖 TL;DR for AI agents** (read this first — saves you scanning the full doc): > > - **Canvas**: `rgb(250, 249, 245)` is the page background. Every component composits against this. > - **Accent**: `rgb(20, 20, 19)` for primary CTAs ONLY. Never decorative. > - **Body type**: 20px (token: `typography.body`). Default for ALL text not in a heading role. > - **Section rhythm**: 48px between major bands. Card padding: 24px. > - **Default radius**: 16px on buttons/inputs. Pills (`9999px`) only for icon-buttons or status chips. > > **Before generating UI**: import this DESIGN.md, scan §2 (Color Palette) + §4 (Components) + §10 (Agent Guide). Skip §11–12 unless extending. ## 1. Visual Theme & Atmosphere anthropic.com's canvas is a warm, intentionally-tinted surface (`#faf9f5`) — a refusal of the default white that immediately signals editorial intent. This isn't sterility, it's an invitation to read. Typography is anchored in **Anthropic Serif**. Headlines use weight 700 for confident, assertive presence — the brand wants to be heard. Body text reads in Near-Black (`#141413`) — softened from pure black, a small but deliberate detail that lowers reading friction. **Near-Black** (`#141413`) provides interactive distinction without visual aggression. Elevation comes from a small, deliberate set of shadows (1 distinct), each a multi-layer stack — several blurred layers at varying offsets — used sparingly rather than across the whole UI. Border radius varies from pill-shaped (fully rounded) to moderately rounded elements, creating visual rhythm. Motion design uses smooth easing curves for polished state transitions. The site uses a variable font with OPSZ axes, enabling precise weight/width control across the type hierarchy. **Key Characteristics:** - Background: Off-White (`#faf9f5`) - Primary typeface: Jetbrains Mono - Primary text: Near-Black (`#141413`) - Accent: Near-Black (`#141413`) - Display: 60.8653px weight 700 - Shadow system: 1 distinct elevation levels - Custom fonts loaded: Jetbrains Mono, Anthropic Sans, Anthropic Serif, Anthropic Mono ## 2. Color Palette & Roles ### Background & Surface - **Off-White** (`#faf9f5`): Page background (primary) - **Whitesmoke** (`#f0eee6`): Surface / elevated background - **Off-White** (`#f9f9f7`): Surface / elevated background - **Vibrant Yellow** (`#f5e3c7`): Surface / elevated background - **#e3dacc** (`#e3dacc`): Surface / elevated background ### Text & Content - **Near-Black** (`#141413`): Primary body text - **Pure Black** (`#000000`): Secondary text - **Near-Black** (`#181818`): Secondary text - **Near-Black** (`#101010`): Secondary text ### Accent & Interactive - **Terracotta** (`#c6613f`): Interactive / accent ### Full Extracted Palette **12 colors rendered on the page** + **13** more declared in design tokens (CSS custom properties — not necessarily painted). (10 categorized above + 15 additional below.) Rendered values are read via `getComputedStyle()`; token values come from CSS variable declarations. Third-party logo colors are filtered out. - `#87867f` — Slate Grey - `#b0aea5` — Cool Gray - `#d97757` — Warm Terracotta *(token)* - `#3d3d3a` — Charcoal *(token)* - `#5e5d59` — Slate Grey *(token)* - `#c46686` — #c46686 *(token)* - `#bcd1ca` — Silver *(token)* - `#ebcece` — Pink *(token)* - `#cbcadb` — Silver *(token)* - `#788c5d` — Stone *(token)* - `#d4a27f` — #d4a27f *(token)* - `#e8e6dc` — Beige *(token)* - `#d1cfc5` — Silver *(token)* - `#ebdbbc` — #ebdbbc *(token)* - `#6a9bcc` — Cornflower Blue *(token)* ### CSS Custom Properties (Design Tokens) **Spacing Token** - `--_spacing---space--11`: `clamp(3.5rem, 2.7346938775510203rem + 3.2653061224489797vw, 6rem)` - `--_spacing---section-space--extra-small`: `clamp(1.75rem, 1.6734693877551021rem + 0.326530612244898vw, 2rem)` - `--_typography---letter-spacing--0em`: `0em` - `--_spacing---section-space--medium`: `clamp(3.5rem, 2.7346938775510203rem + 3.2653061224489797vw, 6rem)` **Font Weight Token** - `--_text-style---font-weight`: `400` **Font Size Token** - `--_text-style---font-size`: `1.25rem` - `---font-size--paragraph-m`: `clamp(1.125rem, 1.086734693877551rem + 0.163265306122449vw, 1.25rem)` - `--_typography---font-size--paragraph-xs`: `1rem` - `---font-size--paragraph-s`: `clamp(1rem, 0.9617346938775511rem + 0.163265306122449vw, 1.125rem)` **Border Radius Token** - `--radius--main`: `.5rem` - `--radius--large`: `1rem` - `--radius--round`: `100vw` - `--radius--small`: `.25rem` **Motion Token** - `--nav--menu-open-duration`: `400ms` - `--nav--dropdown-duration`: `200ms` - `--nav--dropdown-open-duration`: `200ms` **Font Family Token** - `--_text-style---font-family`: `"Anthropic Serif",Georgia,sans-serif` **Other tokens** - `--_color-theme---border`: `#1414131a` - `--_color-theme---button-primary--border-hover`: `#3d3d3a` - `--_color-theme---button-primary--text`: `#faf9f5` - `--_color-theme---button-tertiary--border`: `#1414131a` - `--_button-style---text`: `#faf9f5` - `--align--text-right`: `right` - `--_color-theme---button-primary--text-hover`: `#faf9f5` - `--_typography---font--display-sans`: `"Anthropic Sans",Arial,sans-serif` ## 3. Typography Rules ### Font Families - **Primary**: `Anthropic Serif` - **Secondary**: `Anthropic Sans` - **Font 3**: `webflow-icons` - **Font 4**: `Jetbrains Mono` - **Font 5**: `Anthropic Mono` ### Custom Fonts Loaded - **webflow-icons** weight 400 (normal) - **Jetbrains Mono** weight 400 (normal) - **Anthropic Sans** weight 300 800 (normal) - **Anthropic Serif** weight 300 800 (normal) - **Anthropic Mono** weight 300 800 (normal) ### Typography Hierarchy | Role | Font | Size | Weight | Line Height | Letter Spacing | Notes | |------|------|------|--------|-------------|----------------|-------| | Display Hero | Anthropic Serif | 68.3429px | 400 | 1.1 | normal | Main headline (h2) | | Sub-heading | Anthropic Sans | 24px | 600 | 1.3 | normal | Third-level heading (h3) | | Body | Anthropic Serif | 20px | 400 | 1.4 | normal | Standard reading text | | Link Large | Anthropic Serif | 18px | 600 | 1.4 | normal | Link (18px) — Decoration: 1px | | Button Large | Anthropic Sans | 16px | 400 | 1 | -0.08px | Button label (16px) | | Link Large | Anthropic Serif | 16px | 400 | 1.4 | normal | Link (16px) — Decoration: 1px | | Caption / Badge | Anthropic Sans | 16px | 500 | 1.4 | normal | small text (16px) | | Button | Anthropic Sans | 15px | 400 | 1 | -0.08px | Button label (15px) | ### Full Font Size Scale Sizes detected in the design (descending): `68.34px`, `60.87px`, `24px`, `20px`, `18px`, `16px`, `15px`, `14px`, `12px` > 3 size(s) detected outside the sampled hierarchy (60.8653px, 14px, 12px). These appear on elements not in the sampled set — likely additional display sizes, marketing-section overrides, or third-party-widget styles. ### OpenType & Variable Font Features **Variable font axes:** - OPSZ axis ## 4. Component Stylings ### Buttons **Ghost** - Background: `transparent` - Text: `#141413` `{colors.hairline}` - Padding: 22.4px 12px - Radius: 0px - Font: 20px weight 400 - Use: Subtle action, toolbar, nav button **Ghost** - Background: `transparent` - Text: `#141413` `{colors.hairline}` - Padding: 0px 0px 0px 12px - Radius: 0px - Font: 20px weight 400 - Use: Subtle action, toolbar, nav button **Dark / Solid** - Background: `#141413` `{colors.hairline}` - Text: `#faf9f5` `{colors.background}` - Padding: 8px 16px - Radius: 8px 0px 0px 8px - Border: 1px solid rgb(20, 20, 19) - Font: 16px weight 400 - Use: Solid dark CTA **Dark / Solid** - Background: `#141413` `{colors.hairline}` - Text: `#faf9f5` `{colors.background}` - Padding: 8px 16px - Radius: 8px - Border: 1px solid rgb(20, 20, 19) - Font: 16px weight 400 - Use: Solid dark CTA **Pill** - Background: `transparent` - Text: `#141413` `{colors.hairline}` - Padding: 0px - Radius: 8px - Font: 16px weight 400 - Use: Status pills, tags, chips **Light / Invert** - Background: `#faf9f5` `{colors.background}` - Text: `#141413` `{colors.hairline}` - Padding: 12px 31.4776px - Radius: 0px 0px 8px 8px - Font: 18px weight 600 - Use: Bright CTA on dark sections ## 4b. Component Behaviors (State Matrix) ### Interaction State Narrative *State transitions extracted via Playwright simulation — exact values in the YAML matrix below.* ```yaml component-behaviors: button: default: bg: "rgba(0, 0, 0, 0)" fg: "rgb(20, 20, 19)" link: default: bg: "rgb(250, 249, 245)" fg: "rgb(20, 20, 19)" navLink: default: bg: "rgba(0, 0, 0, 0)" fg: "rgb(20, 20, 19)" hover: bg: "transparent" fg: "inherit" badge: default: bg: "rgba(0, 0, 0, 0)" fg: "rgb(20, 20, 19)" footerLink: default: bg: "rgba(0, 0, 0, 0)" fg: "rgb(176, 174, 165)" hover: bg: "transparent" fg: "inherit" ``` **Agent usage**: Validate generated components against this matrix. If your output's `:hover` state changes properties not listed here, you are off-brand. ## 4c. Component Vocabulary (Closed System) *This brand uses ONLY the following component vocabulary. Introducing new variants without justification breaks the system's tonal coherence.* ### Buttons - **4 shape(s)** in this system: `Ghost`, `Dark / Solid`, `Pill`, `Light / Invert` - **DO NOT introduce new buttons variants** without justification ## 5. Layout Principles ### Layout Type **top-nav + content** ### Grid Flexbox column ### Max Width min(89.5rem, 100vw) ### Spacing System Compact spacing — information density prioritized | Token | Value | |-------|-------| | xxs | 2px | | xs | 4px | | sm | 8px | | md | 12px | | base | 16px | | lg | 24px | | xl | 32px | | 2xl | 48px | | 3xl | 64px | ### Border Radius Scale | Name | Value | Use | |------|-------|-----| | None | 0px | No rounding | | Xs | 8px | Tiny corners (badges, micro elements) | | Sm | 16px | Buttons, inputs, small elements | | Md | 24px | Cards, containers | | Lg | 1600px | Large rounded elements, pill segments | | Xl | 1608px | Category strips, featured containers | | Full | 1600px | Pills, avatars, circular elements | ### Shape Language | Component | Border Radius | |-----------|---------------| | Buttons | `0px` | | Page Body | `0px` | | Navigation | `0px` | **Shape Personality**: Sharp & Angular — No rounding. Precise, editorial, enterprise feel. **Full Radius Spectrum**: 0px, 8px, 16px, 24px, full/pill (from `allBorderRadii` scan) ## 5b. Spacing Rhythm Names **Measured section padding**: bands use ~76px internal vertical padding (up to 91px) — **generous**. (Distinct from the gap *between* sections above.) Reproduce this generous vertical breathing room; cramped spacing is the #1 tell of a cheap clone. *Named spacing tokens with explicit use cases. Use these names in YOUR code instead of raw pixels for consistency.* | Name | Value | Use case | |------|-------|----------| | **hero** | `64px` | Top/bottom of full-bleed hero sections | | **section** | `32px` | Between major bands (color change, content shift) | | **subsection** | `24px` | Within a section, between content groups | | **card** | `12px` | Card padding, list-item spacing | | **compact** | `8px` | Form fields, tight clusters, badge padding | | **micro** | `4px` | Icon-text gap, tag inner padding | **Agent rule**: NEVER hardcode raw pixel values for spacing in generated UI. Always reference these named tokens (`spacing-rhythm.section`, etc.). ## 5c. Widget & Structure Library Structural patterns extracted from the page DOM — these are the **blueprints** an agent should follow to reproduce the page architecture (not just CSS values). **4/8 structural patterns detected.** ### Hero Pattern - **Composition:** left-aligned — - **Viewport coverage:** 179px tall (not full-viewport) - **Heading:** "AI research and products that put safety at the frontierAI research and products that put safety at " — 61px left-aligned - **Subheading:** "AI will have a vast impact on the world. Anthropic is a public benefit corporation dedicated to securing its benefits and mitigating its risks." - **CTAs:** none detected in hero (unusual — agent should verify) - **Clone instruction:** Reproduce the **left-aligned** layout. Use the heading font-size token at the documented size. No imagery needed for hero — text-driven. ### Navigation Pattern - **Position:** static (scrolls with page) - **Layout:** unknown — Layout not classified - **Height:** 68px - **Logo:** ✓ present - **Nav links:** 4 primary items - **CTAs in nav:** 0 (no buttons — links only) - **Clone instruction:** Build a static unknown navigation. Link-only — no button styling needed. ### Card Grid Pattern - **Card count:** 4 cards detected - **Columns (desktop):** 7-up grid - **Card dimensions:** 215×714px (aspect 0.3:1) - **Gap:** 31px between cards - **Content:** ✗ no image - **Clone instruction:** Build a 7-column grid (desktop) with cards at ~0.3:1 aspect ratio. Text/icon-only cards (no photography). ### Footer Pattern - **Columns:** 2 - **Links:** 83 total - **Height:** 865px - **Includes:** ✗ no newsletter | ✓ social icons | ✓ copyright - **Clone instruction:** Build a 2-column footer with ~42 links per column, social media links, and a copyright line. ## 6. Depth & Elevation | Level | Treatment | Use | |-------|-----------|-----| | Flat (Level 0) | No shadow | Page background, content blocks | | Layered (Level 1) |
`rgba(0, 0, 0, 0.01) 0px 2px 2px 0px`,
`rgba(0, 0, 0, 0.02) 0px 4px 4px 0px`,
`rgba(0, 0, 0, 0.04) 0px 16px 24px 0px` | Cards, elevated surfaces | **Shadow Philosophy**: Multi-layered shadow system creating natural, atmospheric depth. Each shadow level combines multiple layers for realistic elevation. ## 7. Motion & Interaction ### Dominant Easing Curves | Curve | Semantic Name | |-------|---------------| | `cubic-bezier(0.16,1,0.3,1)` | Ease Out — Decelerating | | `cubic-bezier(0.77,0,0.175,1)` | Quart In-Out — Precise Symmetric | ### Duration Scale | CSS Variable | Value | Tier | |--------------|-------|------| | `--nav--menu-open-duration` | `400ms` | Slow | | `--nav--dropdown-duration` | `200ms` | Normal | | `--nav--dropdown-open-duration` | `200ms` | Normal | | `--nav--menu-close-duration` | `400ms` | Slow | ### Copy-Paste Transition Snippets **Transform** ```css transition: transform 0.2s, color 0.2s; ``` **All Props** ```css transition: text-decoration-color 0.2s; ``` **Transform** ```css transition: transform 0.2s; ``` **Opacity** ```css transition: opacity 0.4s cubic-bezier(0.77, 0, 0.175, 1); ``` ### Keyframe Animation Catalog | Animation Name | Type | Animated Props | Use Hint | |----------------|------|----------------|----------| | `spin` | Rotate / Spin | transform | Loading indicator | | `marquee` | Slide | transform | UI transition | | `fadein` | Fade | opacity | Element entrance | | `menuOpen` | Custom | clip-path | UI transition | | `menuClose` | Custom | clip-path | UI transition | ### Motion Fingerprint - **Speed Character**: Deliberate & Calm (median duration: `336ms`) - **Dominant Easing**: custom cubic-bezier curves - **Animation Library**: 5 unique animations (5 total including variants) > This design moves with deliberate & calm timing using custom cubic-bezier curves, creating a UI that feels calm and controlled. ## 8. Do's and Don'ts ### Do - Use Off-White (`#faf9f5`) as the page background — it's intentionally not pure white - Use Near-Black (`#141413`) for text — not pure black, it's warmer and more readable - Use Anthropic Serif as the primary typeface — it defines the brand personality - Use the extracted shadow patterns for elevation — they are tuned to match the brand palette - Use full-pill radius (9999px) only for specific elements (avatars, pills, toggles) - Use Near-Black (`#141413`) as the primary accent — it's the brand's signature interactive color - Use 8px 0px 0px 8px border-radius on buttons — the standard corner rounding for interactive elements - Maintain nav height at 68px — consistent vertical space for the navigation bar - Respect the 4px–32px spacing range — the design uses a wide scale for visual breathing room - Use a 7-column grid on desktop — density matters for this content type ### Don't - Don't use pure white (`#ffffff`) as a page background — the warm tone is part of the brand identity - Don't use pure black (`#000000`) for text — the near-black adds warmth - Don't substitute with generic sans-serif or serif — the custom font carries the brand - Don't invent new shadow values — use only the extracted shadow levels - Don't apply pill radius on rectangular buttons or cards — it's reserved for specific interactive elements - Don't introduce additional saturated accent colors — the palette is intentionally controlled - Don't collapse or hide the nav on scroll without an explicit scroll-triggered animation — the design uses fixed nav presence - Don't make the nav sticky — this design lets it scroll away to maximize content focus - Don't put a CTA button in the nav — this design uses links only at the top ## 7b. Enforceable Brand Rules *Structured Do/Don't with reasoning and validation tests. Agents can programmatically verify generated UI.* ```yaml rules: - id: brand-canvas-001 type: do rule: "Always use the page background `rgb(250, 249, 245)` as the base canvas" why: "Every component is designed to composit against this exact tone" test: "document.body.style.backgroundColor === 'rgb(250, 249, 245)'" - id: brand-accent-001 type: do rule: "Reserve `rgb(20, 20, 19)` for primary CTAs and brand-mark signals only" why: "Single chromatic assertion device — overuse dilutes meaning" test: "querySelectorAll('[style*=\"rgb(20, 20, 19)\"]').length <= 3 per fold" ``` ## 9. Responsive Behavior ### Breakpoints | Name | Width | Key Changes | |------|-------|-------------| | Mobile | 479px | Single column, compact spacing | | Mobile Large | 767px | Expanded mobile layout | | Tablet | 991px | Multi-column grids begin | ### Token Diff — Desktop vs Mobile | Element | Property | Desktop | Mobile | |---------|----------|---------|--------| | heading | font-size | `60.8653px` | `40.2939px` | | heading | line-height | `66.9518px` | `44.3233px` | | nav | height | `68px` | `auto` | | button | width | `139.594px` | `100%` | ### Collapsing Strategy - Headlines: 60.8653px → 40.2939px on mobile - Navigation: horizontal links → hamburger menu on mobile - Cards: multi-column → stacked vertical on mobile - Footer: multi-column → stacked single column on mobile ### Touch Targets - Buttons: 22.4px 12px padding - Navigation: adequate spacing between items - Interactive elements: minimum 44px touch target recommended ### Collapsing Narrative How the structural patterns adapt from desktop to mobile (extracted from both viewport extractions): - **Card grid: 7-up → 1-up** — cards stack as viewport narrows, becoming a vertical list on mobile. ## 7c. Visual Effects & Dynamic Behavior *The live/dynamic layer beyond static CSS — reproduce these, not flat substitutes. This is often what separates a faithful clone from a wireframe.* - **Clip-path shapes** — 8 non-rectangular cut(s). > **Motion fingerprint**: non-rectangular shapes (10) ## 9b. Visual Tone & Photography **Tone:** No imagery No detectable photographic content. The site composes entirely with typography, color blocks, and minimal vector graphics. Clone strategy: lean on type hierarchy + layout rhythm rather than visual media. **Canonical Brand Image (OG):** - https://cdn.prod.website-files.com/67ce28cfec624e2b733f8a52/68309ab48369f7ad9b4a40e1_open-graph.jpg *This is the image shown when the site is shared on social media — represents the brand visual essence.* **Media Format Mix:** - *No detectable images.* **Imagery Guidance for clones:** - Don't add stock imagery just to "fill space" — this site's clarity comes from typographic restraint. - Use generous whitespace, strong type hierarchy, and color blocks for visual rhythm. ## 10. Agent Prompt Guide ### Quick Reference - Background: Off-White (`#faf9f5`) - Primary text: Near-Black (`#141413`) - Accent: Near-Black (`#141413`) - Border: Translucent Jet Black (10%) (`rgba(20, 20, 19, 0.1)`) - Font: Anthropic Serif - Body: 20px weight 400 ### Example Component Prompts - "Create a hero section on Off-White background (#faf9f5). Headline at 60.8653px Anthropic Serif weight 700, line-height 1.1, color #141413." - "Create the primary CTA button: `#141413` background, `#141413` text, 1600px border-radius, 22.4px 12px padding, 700 weight, Anthropic Serif font." - "Build navigation: static on `#faf9f5`. Anthropic Serif 20px weight 400 for links." ### Iteration Guide 1. **Canvas**: Set the light canvas to Off-White (`#faf9f5`) — every component is composited against this exact base. 2. **Typography**: All type in Anthropic Serif, weight range 400–700. Never exceed 700 — heavier weights break the brand's tonal restraint. 3. **Accent**: Near-Black (`#141413`) is the sole interactive color. On hover → Terracotta (`#c6613f`). Use CSS transitions, not opacity/brightness filters. 4. **Motion**: All transitions use `cubic-bezier(0.77,0,0.175,1)`. Timing: 200ms for micro-interactions, 400ms for layout changes. Never use linear for UI transitions — preserve the brand's easing personality. 5. **Shape**: CTAs at `0px`. Apply border-radius from the extracted scale only — don't invent intermediate values. 6. **Spacing**: Use the `--ca-space-*` token scale (4px–32px). All padding, margin, and gap values are multiples from this scale — no magic numbers. 7. **Tokens**: Import from §11 CSS Export (`--ca-*` vars). Never hardcode hex values — always reference a token so theming remains consistent. ## 11. CSS Design Tokens Raw Export *Copy-paste ready `:root {}` block — all values extracted directly from the live site.* ```css /* Colors */ :root { --ca-background: #faf9f5; --ca-surface-1: #f0eee6; --ca-surface-2: #f9f9f7; --ca-hairline: #141413; --ca-on-primary: #ffffff; --ca-primary-hover: #3d3d3a; } /* Typography */ :root { --ca-font-primary: "Anthropic Serif", system-ui, sans-serif; --ca-text-display: 68.3429px; --ca-text-body: 20px; --ca-text-small: 18px; --ca-text-caption: 16px; --ca-text-button: 16px; } /* Spacing & Radius */ :root { --ca-space-xxs: 2px; --ca-space-xs: 4px; --ca-space-sm: 8px; --ca-space-md: 12px; --ca-space-base: 16px; --ca-space-lg: 24px; --ca-space-xl: 32px; --ca-space-2xl: 48px; --ca-space-3xl: 64px; --ca-radius-none: 0px; --ca-radius-xs: 8px; --ca-radius-sm: 16px; --ca-radius-md: 24px; --ca-radius-lg: 1600px; --ca-radius-xl: 1608px; --ca-radius-full: 1600px; } ``` ## 13. Page Structure Skeleton *The actual layout the source site uses. Reproduce these sections in order to match the site structure.* ```yaml page-skeleton: - section: hero tag: main classes: ["page_wrap", "u-bg-ivory-medium"] height: 3351px width: full-bleed layout: flex-column justify=normal children: 7 bg: "rgb(240, 238, 230)" - section: header tag: header classes: ["hero_wrap"] height: 390px width: full-bleed layout: flex-column justify=normal children: 3 - section: feature-section tag: div height: 179px width: 1285px layout: block children: 1 - section: feature-section tag: div classes: ["home_hero_grid", "u-grid-tablet"] height: 179px width: 1285px layout: grid: 12-col gap=31.4776px children: 2 - section: unknown tag: div classes: ["home_hero_bump"] height: 123px width: 517px layout: block children: 1 padding: "0px 0px 5px" - section: hero tag: section height: 946px width: full-bleed layout: flex-column justify=center children: 3 - section: feature-section tag: div classes: ["is-fable-marmot"] height: 824px width: 1285px layout: flex-row justify=space-between children: 2 vertical-padding: ~91px (generous) padding: "90.7755px 0px" - section: feature-section tag: div classes: ["g_section_wrap"] height: 623px width: full-bleed layout: flex-column justify=center children: 2 - section: feature-section tag: div classes: ["u-radius-medium"] height: 532px width: 1285px layout: block children: 2 - section: feature-section tag: section classes: ["g_section_wrap"] height: 458px width: full-bleed layout: flex-column justify=center children: 3 - section: feature-section tag: div height: 368px width: 1285px layout: block children: 2 - section: footer tag: footer classes: ["footer_wrap", "u-theme-dark"] height: 865px width: full-bleed layout: block children: 3 bg: "rgb(20, 20, 19)" tone: dark vertical-padding: ~76px (generous) - section: footer tag: div height: 865px width: 1285px layout: block children: 1 vertical-padding: ~76px (generous) padding: "75.8204px 0px" - section: navigation tag: nav classes: ["footer_grid"] height: 714px width: 1285px layout: grid: 12-col gap=31.4776px children: 3 - section: footer tag: section classes: ["footer_group_wrap"] height: 714px width: 215px layout: flex-column justify=normal children: 2 - section: footer tag: section classes: ["footer_group_wrap"] height: 714px width: 215px layout: flex-column justify=normal children: 2 - section: footer tag: section classes: ["footer_group_wrap"] height: 714px width: 215px layout: flex-column justify=normal children: 2 - section: footer tag: section classes: ["footer_group_wrap"] height: 714px width: 215px layout: flex-column justify=normal children: 2 ``` **Agent rule**: rebuild sections in this order (sorted by vertical position). Match the layout primitive (grid N-col / flex direction / block). ## 14. Copy Library (Real Content from Source) *Actual text content extracted from the live page. Use these strings verbatim when reproducing the site — they carry the brand voice.* ```yaml copy: section-headings: - "Announcing Fable 5" - "Latest releases" - "At Anthropic, we build AI to serve humanity’s long-term well-being." sub-headings: - "Expanding Project Glasswing" - "Claude Opus 4.8" - "Core views on AI safety" - "Products" ctas: - "Commitments" - "Try Claude Try Claude Learn more about Claude" - "Try Claude Try Claude" - "Try Claude" - "Learn more about Claude" - "Continue reading" - "Read announcement Read announcement" - "Model details Model details" navigation: - "Try Claude" - "Skip to main content" - "Skip to footer" - "Research" - "Policy" - "News" - "research" - "products" - "Claude" - "Claude Code" footer-links: - "Claude" ``` **Agent rule**: reuse these exact strings when generating UI. Do NOT translate or rephrase — brand voice is preserved through the original wording. ## 16. Component HTML Templates *Suggested HTML markup for reproducing the key components — based on what was detected in the source DOM.* ### Button (primary action) ```html ``` _Source pattern detected: padding `22.4px 12px` · radius `0px` · weight `400`_ **Agent rule**: use these markup skeletons as the structural baseline. Apply tokens from §2-3 for visual styling. ## 17. Content Architecture & Resources (Links by Purpose) *The page's links classified by purpose — the information architecture to reproduce. Categories, featured images, devices and projects are extracted from the rendered DOM, not guessed.* **By purpose:** **nav** 6 · **cta** 1 · **auth** 1 · **product** 21 · **pricing** 5 · **docs** 1 · **blog** 6 · **social** 3 · **footer** 7 · **other** 9 **Primary actions (conversion path):** - Primary call-to-action — "Try Claude" (the conversion path) → `https://claude.ai/` - Account access — "Log in to Claude" (login/signup) → `https://claude.ai/login` **Signals:** 5/60 links carry a featured image · device mockups detected: phone ×1 · dominant link roles: footer-link (21), inline-link (16), content-card (16). --- ## Extraction Completeness: 68/100 (C) | Category | Score | Max | Detail | |----------|-------|-----|--------| | Colors & Palette | 14 | 25 | 10 named colors | | Typography | 20 | 20 | 8 roles defined | | Components | 4 | 20 | 1 specs extracted | | Motion & Interaction | 12 | 15 | Keyframes | | CSS Custom Properties | 10 | 10 | 282 vars | | Responsive Breakpoints | 3 | 5 | 3 breakpoints | | Variable Fonts | 5 | 5 | OPSZ axes | ## 12. Known Gaps & Confidence Explicit list of what this extraction could NOT capture. Agents should not invent values for these — either skip the feature or use the documented baseline + heuristic fallback. *Auto-detected extraction limitations — understand before building:* - **Licensed web fonts (webflow-icons, Jetbrains Mono, Anthropic Sans)** — detected but not downloaded. Substitute with your licensed copy or a close fallback (see Typography section for metrics). - **Sparse component extraction** — fewer than 5 component types detected. Highly dynamic sections (modals, datepickers, carousels) require interaction to render and are not captured in a static pass. | Category | What's missing | Fallback strategy | |----------|----------------|-------------------| | **Photography** | No photographic content detected on this page | Don't add stock imagery; clarity comes from type + color blocks | | **Form inputs** | No text input fields detected on this page | Use the documented border-radius + accent border on focus; 12-16px padding inside | ### Per-section confidence | Section | Confidence | Reason | |---------|------------|--------| | §1 Visual Theme | High | Body bg extracted via getComputedStyle() | | §2 Colors | High | 282 CSS vars (semantic naming requires ≥20 for high) | | §3 Typography | High | 8 typography roles inferred | | §4 Components | Low | 1 component variants captured | | §7 Motion | High | Keyframes + transitions | | §8 Do's/Don'ts | High | 19 rules generated; design-decisions.json has evidence per rule | | §9 Responsive | High | 3 breakpoints detected | | §9b Photography | Low | 0 images, hero not detected | ## 11.1 CSS Implementation Guide (CSS Interception Engine v2.15+) *Ready-to-use CSS from Prism's CSS Interception Engine — intercepted directly from the site's CSS files (bypasses CORS). Copy-paste into your `