--- version: alpha name: trpc.io description: "Light product system built on #ffffff with #398ccb as the primary CTA accent. Type anchored in system-ui at 48px / weight 800. Extracted automatically from https://trpc.io/ — rendered styles via getComputedStyle() + CSS custom properties (token-only values may not be painted)." narrative: | trpc.io is built on a pure-white canvas (rgb(255,255,255)). The system uses rgb(57, 140, 203) as the accent for primary actions and brand signals. Sharp 0px corners on CTAs — architectural restraint, engineering precision alongside system-ui as the primary typeface. A layered elevation system (8 distinct shadows) building a clear front-to-back hierarchy. Motion is a first-class concern — 6 keyframe animations plus transition-driven interactions. colors: background: "#ffffff" surface-1: "#ffffff" surface-2: "#f4f4f5" ink: "#1c1e21" ink-muted: "rgba(28, 30, 33, 0.65)" ink-subtle: "#474748" primary: "#398ccb" on-primary: "#111111" hairline: "#969faf" semantic-error: "#fd9c9f" semantic-success: "#008b00" semantic-warning: "#e6a700" semantic-info: "#87d8f2" typography: display-xl: fontFamily: "Inter, 'SF Pro Display', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif" fontSize: 48px fontWeight: 800 lineHeight: 1 letterSpacing: -1.2px display-lg: fontFamily: "Ubuntu, 'SF Pro Display', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif" fontSize: 48px fontWeight: 800 lineHeight: 1 letterSpacing: -1.2px display-md: fontFamily: "Ubuntu, 'SF Pro Display', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif" fontSize: 20px fontWeight: 700 lineHeight: 1.4 letterSpacing: 0 body: fontFamily: "ui-sans-serif, Georgia, 'Times New Roman', serif" fontSize: 16px fontWeight: 400 lineHeight: 1.5 letterSpacing: 0 body-sm: fontFamily: "ui-sans-serif, Georgia, 'Times New Roman', serif" fontSize: 14px fontWeight: 500 lineHeight: 1.5 letterSpacing: 0 button: fontFamily: "ui-sans-serif, Georgia, 'Times New Roman', serif" fontSize: 18px fontWeight: 700 lineHeight: 1.56 letterSpacing: 0 eyebrow: fontFamily: "ui-monospace, 'SF Mono', 'JetBrains Mono', Menlo, monospace" fontSize: 16px fontWeight: 400 lineHeight: 1.5 letterSpacing: 0 rounded: none: 0px xs: 4px sm: 8px md: 12px lg: 16px xl: 9999px spacing: xxs: 2px xs: 4px sm: 8px md: 12px lg: 24px xl: 32px xxl: 60px components: button-light--invert: backgroundColor: "{colors.surface-2}" textColor: "{colors.hairline}" typography: "{typography.body}" rounded: "{rounded.xs}" padding: 0px 8px button-primary-brand: backgroundColor: "{colors.primary}" textColor: "{colors.surface-1}" typography: "{typography.button}" rounded: "{rounded.sm}" padding: 8px 16px button-dark--solid: backgroundColor: "#171717" textColor: "{colors.primary}" typography: "{typography.body}" rounded: "{rounded.sm}" navigation-main-nav: backgroundColor: "transparent" typography: "{typography.body}" rounded: "{rounded.none}" padding: 96px 0px 0px code-block-inline-code--pre: backgroundColor: "{colors.surface-1}" textColor: "#24292e" typography: "{typography.body}" rounded: "{rounded.sm}" extracted_at: "2026-06-11T06:19:05.119Z" completeness: 84 scoreVersion: "v2" --- # Design System — trpc.io > Extracted automatically by Prism from https://trpc.io > 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). > ⚠️ **LOW-CONFIDENCE CAPTURE** — this extraction likely sampled an app shell / interactive demo, **not** the marketing page. Signals: button labels look like filenames (Node.js); only 0 card component detected. Treat the component, color and copy values below with caution, and re-extract the canonical marketing URL if fidelity matters. ## 0. Design DNA **Density**: moderate  |  **Motion**: subtle  |  **Weight**: heavy  |  **Aesthetic**: product-neutral | Dimension | Value | Signal | |---|---|---| | Canvas | neutral | `#ffffff` | | Type posture | sans-led (Roboto) | "Move Fast and Break Nothing. E" | | Color assertion | dual-accent | #398ccb | | Whitespace | moderate | section rhythm 48px | | Interaction | subtle | 6 keyframes, 17 transitions | | Radius language | 8px-rounded | from token scale | **Prism fingerprint**: `neutral-canvas · sans-display · dual-accent · 8px-rounded · subtle-motion` > **🤖 TL;DR for AI agents** (read this first — saves you scanning the full doc): > > - **Canvas**: `rgb(255,255,255)` is the page background. Every component composits against this. > - **Accent**: `rgb(57, 140, 203)` for primary CTAs ONLY. Never decorative. > - **Body type**: 16px (token: `typography.body`). Default for ALL text not in a heading role. > - **Section rhythm**: 48px between major bands. Card padding: 24px. > - **Default radius**: 8px 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 **Signature:** a radial gradient glow in the hero — colours: #f4f4f5, #262626. This is the brand's most recognizable visual — reproduce it, don't replace it with a generic card or flat panel. trpc.io uses a pure-white canvas (`#ffffff`), letting typography, color and imagery carry the visual weight. Headlines are set in **system-ui**, a sans-serif display face (the dominant type signature, e.g. "Move Fast and Break Nothing. End-to-end typesafe APIs made e" at 48px). Body text is set in **Roboto**. Headlines use weight 800 for confident, assertive presence — the brand wants to be heard. Negative letter-spacing at display sizes (-1.2px at 48px) compresses headlines into engineered blocks, dense and precise. Body text reads in Near-Black (`#1c1e21`) — softened from pure black, a small but deliberate detail that lowers reading friction. **Steel Blue** (`#398ccb`) is the single high-saturation color in the system — it earns its presence only on interactive elements, making CTAs and links the unmistakable focal points against the otherwise neutral palette. Elevation is built from multi-layer shadow stacks (8 distinct) — each combines several blurred layers at varying offsets to build a clear front-to-back hierarchy. 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. **Key Characteristics:** - Background: Pure White (`#ffffff`) - Primary typeface: Inter - Primary text: Near-Black (`#1c1e21`) - Accent: Steel Blue (`#398ccb`) - Display: 48px weight 800, letter-spacing -1.2px - Shadow system: 8 distinct elevation levels - Custom fonts loaded: Inter ## 2. Color Palette & Roles ### Background & Surface - **Pure White** (`#ffffff`): Page background (primary) - **Whitesmoke** (`#e5e7eb`): Surface / elevated background - **Off-White** (`#f4f4f5`): Surface / elevated background - **#fde68a** (`#fde68a`): Surface / elevated background - **Soft Pink** (`#fbcfe8`): Surface / elevated background ### Text & Content - **Near-Black** (`#1c1e21`): Primary body text - **Pure Black** (`#000000`): Secondary text - **Deep Navy** (`#0f172a`): Secondary text - **Charcoal** (`#1e293b`): Secondary text - **Near-Black** (`#171717`): Secondary text ### Accent & Interactive - **Cool Gray** (`#969faf`): Interactive / accent - **Steel Blue** (`#398ccb`): Interactive / accent - **Lavender** (`#c7d2fe`): Interactive / accent - **Deep Purple** (`#4f46e5`): Interactive / accent - **#d97706** (`#d97706`): Interactive / accent - **Cherry** (`#db2777`): Interactive / accent - **#fed7aa** (`#fed7aa`): Interactive / accent ### Border & Divider - **Whitesmoke** (`#dadde1`): Borders / dividers - **Light Grey** (`#c2c3c5`): Borders / dividers - **Whitesmoke** (`#e4e4e7`): Borders / dividers - **Light Blue** (`#c9d1d9`): Borders / dividers ### Full Extracted Palette **50 colors rendered on the page** + **66** more declared in design tokens (CSS custom properties — not necessarily painted). (21 categorized above + 95 additional below.) Rendered values are read via `getComputedStyle()`; token values come from CSS variable declarations. Third-party logo colors are filtered out. - `#52525b` — Charcoal - `#ea580c` — Bright Orange - `#d9f99d` — #d9f99d - `#65a30d` — #65a30d - `#bae6fd` — Light Blue - `#0284c7` — #0284c7 - `#24292e` — Near-Black - `#d32f2f` — M Tricolor Red - `#1976d2` — M Tricolor Blue - `#6f42c1` — Slate Blue - `#ebedf0` — Whitesmoke - `#22863a` — Forest Green - `#212121` — Near-Black - `#f6f7f8` — Off-White - `#18181b` — Near-Black - `#3f3f46` — Charcoal - `#a1a1aa` — Grey - `#444950` — Dark Gray - `#1f2937` — Charcoal - `#ec4899` — #ec4899 - `#f5f6f7` — Off-White - `#606770` — Dim Gray - `#0d1117` — Near-Black - `#ff7b72` — Coral - `#79c0ff` — Baby Blue - `#d2a8ff` — Lavender - `#ffa657` — Tangerine - `#a5d6ff` — Light Blue - `#8b949e` — Cool Gray - `#ebf2fc` — Light Gray *(token)* - `#589ed3` — Cornflower Blue *(token)* - `#f1f1f1` — Off-White *(token)* - *…+63 more in `raw-css.json` (`desktop.allColors`).* ### CSS Custom Properties (Design Tokens) **Spacing Token** - `--ifm-menu-link-padding-vertical`: `.375rem` - `--ifm-spacing-vertical`: `1rem` - `--ifm-card-horizontal-spacing`: `1rem` - `--ifm-alert-padding-horizontal`: `1rem` **Primary Brand Color** - `--ifm-color-primary-contrast-background`: `#ebf2fc` - `--ifm-color-primary-lighter`: `#589ed3` - `--ifm-color-primary-dark`: `#317eb9` - `--ifm-color-primary-contrast-foreground`: `#102445` **Font Size Token** - `--ifm-h2-font-size`: `1.5rem` - `--ifm-blockquote-font-size`: `100%` - `--ifm-font-size-base`: `100%` - `--ifm-code-font-size`: `95%` **Font Weight Token** - `--ifm-font-weight-semibold`: `500` - `--ifm-font-weight-base`: `400` - `--ifm-font-weight-normal`: `400` - `--ifm-button-font-weight`: `700` **Success** - `--ifm-color-success-darker`: `#008b00` - `--ifm-color-success-contrast-foreground`: `#003100` - `--ifm-color-success-lightest`: `#80d280` - `--ifm-color-success-light`: `#26b226` **Secondary Color** - `--ifm-color-secondary-contrast-background`: `#fdfdfe` - `--ifm-color-secondary-darker`: `#c8c9cc` - `--ifm-font-color-secondary`: `#525860` - `--ifm-color-secondary`: `#ebedf0` **Border Radius Token** - `--ifm-pre-border-radius`: `.4rem` - `--ifm-pagination-nav-border-radius`: `.4rem` - `--ifm-card-border-radius`: `calc(.4rem*2)` - `--ifm-pagination-border-radius`: `.4rem` **Error / Destructive** - `--ifm-color-danger-lightest`: `#fd9c9f` - `--ifm-color-danger-lighter`: `#fb7478` - `--ifm-color-danger-light`: `#fb565b` - `--ifm-color-danger-darker`: `#d53035` **Warning** - `--ifm-color-warning-dark`: `#e6a700` - `--ifm-color-warning-lightest`: `#ffdd80` - `--ifm-color-warning-contrast-background`: `#fff8e6` - `--ifm-color-warning`: `#ffba00` **Z-Index Token** - `--ifm-z-index-overlay`: `400` - `--ifm-z-index-dropdown`: `100` - `--ifm-z-index-fixed`: `200` **Text Color** - `--ifm-color-content`: `#1c1e21` - `--ifm-color-content-inverse`: `#fff` - `--ifm-color-content-secondary`: `#525860` **Motion Token** - `--ifm-transition-fast`: `.2s` - `--ifm-button-transition-duration`: `.2s` - `--ifm-transition-timing-default`: `cubic-bezier(.08,.52,.52,1)` **Shadow Token** - `--ifm-global-shadow-tl`: `0 12px 28px 0 rgba(0,0,0,.2),0 2px 4px 0 rgba(0,0,0,.1)` - `--tw-drop-shadow`: `` - `--ifm-global-shadow-lw`: `0 1px 2px 0 rgba(0,0,0,.1)` - `--ifm-blockquote-shadow`: `none` **Font Family Token** - `--ifm-font-family-monospace`: `SFMono-Regular,Menlo,Monaco,Consolas,"Liberation Mono","Courier New",monospace` **Background** - `--ifm-menu-color-background-hover`: `rgba(0,0,0,.05)` - `--ifm-pills-color-background-active`: `rgba(0,0,0,.05)` - `--ifm-menu-color-background-active`: `rgba(0,0,0,.05)` **Other tokens** - `--ifm-badge-border-color`: `` - `--ifm-table-head-color`: `` - `--ifm-pre-color`: `` - `--ifm-heading-color`: `` - `--ifm-scrollbar-track-background-color`: `#f1f1f1` - `--ifm-color-gray-400`: `#ccd0d5` - `--ifm-blockquote-color`: `#444950` - `--ifm-navbar-link-color`: `#1c1e21` ## 3. Typography Rules ### Font Families - **Primary**: `ui-sans-serif` - **Secondary**: `system-ui` - **Font 3**: `Inter` - **Font 4**: `codicon` - **Font 5**: `ui-monospace` ### Custom Fonts Loaded - **Inter** weight 400 (normal) - **codicon** weight normal (normal) ### Typography Hierarchy | Role | Font | Size | Weight | Line Height | Letter Spacing | Notes | |------|------|------|--------|-------------|----------------|-------| | Display Hero | Inter | 48px | 800 | 1 | -1.2px | Main headline (h1) | | Section Heading | Ubuntu | 48px | 800 | 1 | -1.2px | Section titles (h1) | | Sub-heading | Ubuntu | 20px | 700 | 1.4 | normal | Third-level heading (h3) | | Button Large | ui-sans-serif | 18px | 700 | 1.56 | normal | Button label (18px) | | Body | ui-sans-serif | 16px | 400 | 1.5 | normal | Standard reading text | | Button Large | ui-sans-serif | 16px | 500 | 1.5 | normal | Button label (16px) | | Eyebrow / Overline | ui-monospace | 16px | 400 | 1.5 | normal | Label above heading, uppercase tag | | Link | ui-sans-serif | 14px | 500 | 1.5 | normal | Link (14px) — Decoration: none | ### Font Weight Scale CSS custom properties define 9 explicit weight steps: - `--ifm-font-weight-light`: `300` — Light - `--ifm-font-weight-base`: `400` — Regular - `--ifm-font-weight-normal`: `400` — Regular - `--ifm-font-weight-semibold`: `500` — Medium - `--ifm-dropdown-font-weight`: `500` — Medium - `--ifm-button-font-weight`: `700` — Bold - `--ifm-table-head-font-weight`: `700` — Bold - `--ifm-heading-font-weight`: `700` — Bold - `--ifm-font-weight-bold`: `700` — Bold ### Full Font Size Scale Sizes detected in the design (descending): `48px`, `30px`, `24px`, `20px`, `18px`, `16px`, `14px` > 2 size(s) detected outside the sampled hierarchy (30px, 24px). These appear on elements not in the sampled set — likely additional display sizes, marketing-section overrides, or third-party-widget styles. ## 4. Component Stylings ### Buttons **Light / Invert** - Background: `#f4f4f5` `{colors.surface-2}` - Text: `#969faf` `{colors.hairline}` - Padding: 0px 8px - Radius: 6px - Font: 16px weight 500 - Use: Bright CTA on dark sections **Primary Brand** - Background: `#398ccb` `{colors.primary}` - Text: `#ffffff` `{colors.surface-1}` - Padding: 8px 16px - Radius: 8px - Shadow: `rgba(14, 165, 233, 0.2) 0px 20px 25px -5px, rgba(14, 165, 233, 0.2) 0px 8px 10px...` - Font: 18px weight 700 - Use: Primary CTA / brand action **Dark / Solid** - Background: `#171717` - Text: `#398ccb` `{colors.primary}` - Padding: 0px - Radius: 8px - Border: 20px solid rgb(23, 23, 23) - Shadow: `rgba(57, 140, 203, 0.15) 0px -24px 300px 0px` - Font: 16px weight 400 - Use: Solid dark CTA **Subtle** - Background: `rgba(0, 0, 0, 0.3)` - Text: `#ffffff` `{colors.surface-1}` - Padding: 6.4px 8px - Radius: 6.4px - Font: 16px weight 400 - Use: Quiet action against page bg ### Navigation **Main Nav** - Background: `transparent` - Padding: 96px 0px 0px - Radius: none - Font: 16px weight 400 - Use: Static flex nav — N/A items - Hover: color: `#243e53`, outline: `rgb(36, 62, 83) none 3px` ### Code Blocks **Inline Code / Pre** - Background: `#ffffff` `{colors.surface-1}` - Text: `#24292e` - Padding: 0px - Radius: 6.4px - Border: 1px solid rgb(218, 221, 225) - Font: 16px weight 400 — ui-monospace - Use: Code samples, CLI commands, syntax highlighting blocks ## 4b. Component Behaviors (State Matrix) ### Interaction State Narrative - **NavLink**: - **hover:** text #1c1e21 → #243e53 - **FooterLink**: - **hover:** text #606770 → #4e7899 *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(28, 30, 33)" link: default: bg: "rgb(255, 255, 255)" fg: "rgb(28, 30, 33)" navLink: default: bg: "rgba(0, 0, 0, 0)" fg: "rgb(28, 30, 33)" hover: bg: "transparent" fg: "rgb(36, 62, 83)" footerLink: default: bg: "rgba(0, 0, 0, 0)" fg: "rgb(96, 103, 112)" hover: bg: "transparent" fg: "rgb(78, 120, 153)" ``` **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: `Light / Invert`, `Primary Brand`, `Dark / Solid`, `Subtle` - **DO NOT introduce new buttons variants** without justification ### Navigation - **1 shape(s)** in this system: `Main Nav` - **DO NOT introduce new navigation variants** without justification ### Code Blocks - **1 shape(s)** in this system: `Inline Code / Pre` - **DO NOT introduce new code blocks variants** without justification ## 5. Layout Principles ### Layout Type **top-nav + content** ### Grid Single column, centered content ### Max Width 1320px ### 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 | 60px | ### Border Radius Scale | Name | Value | Use | |------|-------|-----| | None | 0px | No rounding | | Xs | 4px | Tiny corners (badges, micro elements) | | Sm | 8px | Buttons, inputs, small elements | | Md | 12px | Cards, containers | | Lg | 16px | Large rounded elements, pill segments | | Xl | 9999px | Category strips, featured containers | | Full | 9999px | Pills, avatars, circular elements | ### Shape Language | Component | Border Radius | |-----------|---------------| | Buttons | `6px` | | Navigation | `none` | | Code Blocks | `6.4px` | | Page Body | `0px` | **Shape Personality**: Moderate Rounding — Medium corners (4–12px). Modern SaaS standard, neither sharp nor pill. **Full Radius Spectrum**: 0px, 2px, 2.96px, 3px, 4px, 6px, 6.4px, 8px (from `allBorderRadii` scan) ## 5b. Spacing Rhythm Names **Measured section padding**: bands use ~32px internal vertical padding (up to 72px) — **compact**. (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** | `60px` | 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). **5/8 structural patterns detected.** ### Hero Pattern - **Composition:** centered — Centered composition — heading + subheading + CTAs stacked vertically, content centered horizontally. Common for SaaS marketing pages. - **Viewport coverage:** full-viewport hero (≥70% screen height) - **Heading:** "Move Fast and Break Nothing. End-to-end typesafe APIs made easy." — 48px center-aligned - **Subheading:** "Experience the full power of TypeScript inference to boost productivity for your full-stack application." - **Media:** present, positioned top - **CTAs:** 3 (primary: "Star40,311") - **Clone instruction:** Reproduce the **centered** layout. Use the heading font-size token at the documented size. Place media top of text. ### Navigation Pattern - **Position:** sticky (stays visible during scroll) - **Layout:** logo-left-links-left — Logo and links both on the left (CTAs typically right) - **Height:** 60px - **Logo:** ✓ present - **Nav links:** 6 primary items - **CTAs in nav:** 0 (no buttons — links only) - **Theme toggle:** ✓ dark/light mode switcher present - **Clone instruction:** Build a sticky logo left links left navigation. Link-only — no button styling needed. ### Card Grid Pattern - **Card count:** 6 cards detected - **Columns (desktop):** 4-up grid - **Card dimensions:** 408×164px (aspect 2.49:1) - **Gap:** 24px between cards - **Content:** ✗ no image + icon - **Clone instruction:** Build a 4-column grid (desktop) with cards at ~2.49:1 aspect ratio. Text/icon-only cards (no photography). ### Testimonial Pattern - **Count:** 13 testimonial blocks - **Layout:** grid - **Avg quote length:** 198 chars (medium quote) - **Includes:** ✗ no avatars | ✗ no logos | ✗ no ratings - **Clone instruction:** Build a grid of 13 testimonials. ### Footer Pattern - **Columns:** 3 - **Links:** 10 total - **Height:** 276px - **Includes:** ✗ no newsletter | ✓ social icons | - **Clone instruction:** Build a 3-column footer with ~3 links per column, social media links. ## 6. Depth & Elevation | Level | Treatment | Use | |-------|-----------|-----| | Flat (Level 0) | No shadow | Page background, content blocks | | Layered (Level 1) |
`rgba(0, 0, 0, 0.2) 0px 5px 40px 0px` | Cards, elevated surfaces | | Layered (Level 2) |
`rgba(14, 165, 233, 0.2) 0px 20px 25px -5px`,
`rgba(14, 165, 233, 0.2) 0px 8px 10px -6px` | Cards, elevated surfaces | | Layered (Level 3) |
`rgba(0, 0, 0, 0.1) 0px 20px 25px -5px`,
`rgba(0, 0, 0, 0.1) 0px 8px 10px -6px` | Cards, elevated surfaces | | Layered (Level 4) |
`rgba(57, 140, 203, 0.15) 0px -24px 300px 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 ### Easing System | CSS Variable | Curve | Semantic Name | |--------------|-------|---------------| | `--ifm-transition-timing-default` | `cubic-bezier(.08,.52,.52,1)` | Custom Ease — Balanced | ### Duration Scale | CSS Variable | Value | Tier | |--------------|-------|------| | `--ifm-button-transition-duration` | `.2s` | Normal | ### Copy-Paste Transition Snippets **Color / Background** ```css transition: color 0.2s cubic-bezier(0.08, 0.52, 0.52, 1); ``` **Opacity** ```css transition: opacity 0.2s cubic-bezier(0.08, 0.52, 0.52, 1), transform 0.2s cubic-bezier(0.08, 0.52, 0.52, 1), visibility 0.2s cub...; ``` **Background** ```css transition: background 0.2s; ``` **All Props** ```css transition: 0.2s cubic-bezier(0.08, 0.52, 0.52, 1); ``` ### Keyframe Animation Catalog | Animation Name | Type | Animated Props | Use Hint | |----------------|------|----------------|----------| | `infinite-scroll` | Slide | transform | UI transition | | `loader` | Fade + Move | opacity, transform | Loading indicator | | `pulse` | Fade | opacity | Attention / status | | `loading-spin_HK5v` | Rotate / Spin | transform | Loading indicator | | `fade-in` | Fade | opacity | Element entrance | | `loading_zvTa` | Custom | background-position-x, background-position-y | Loading indicator | ### Motion Fingerprint - **Speed Character**: Balanced Pacing (median duration: `200ms`) - **Dominant Easing**: custom cubic-bezier curves - **Animation Library**: 6 unique animations (6 total including variants) > This design moves with balanced pacing timing using custom cubic-bezier curves, creating a UI that feels natural and fluid. ## 8. Do's and Don'ts ### Do - Use Near-Black (`#1c1e21`) for text — not pure black, it's warmer and more readable - Use ui-sans-serif as the primary typeface — it defines the brand personality - Use negative letter-spacing (-1.2px) at display sizes for compressed, editorial headlines - 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 Steel Blue (`#398ccb`) as the primary accent — it's the brand's signature interactive color - Use 8px border-radius on buttons — the standard corner rounding for interactive elements - Keep navigation sticky to the top — the design uses a persistent navigation pattern - Maintain nav height at 60px — consistent vertical space for the navigation bar - Respect the 4px–32px spacing range — the design uses a wide scale for visual breathing room - Make the hero full-viewport (≥70% screen height) — this design uses an immersive hero, not a tall navbar - Include exactly 3 CTAs in the hero (primary + secondary) — this design pattern is multi-action, not single-purpose - Make the navigation sticky — it stays visible during scroll, signaling content depth - Include a theme toggle in the nav — dark mode is a first-class feature - Each card uses an icon (not photo) — the visual language is illustrative, not photographic - Use a 4-column grid on desktop — density matters for this content type - Lay out testimonials in a grid (13+ items) — quantity signals scale and trust ### Don't - 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 increase letter-spacing on headings — the type is designed to run tight at scale - 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 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(255,255,255)` as the base canvas" why: "Every component is designed to composit against this exact tone" test: "document.body.style.backgroundColor === 'rgb(255,255,255)'" - id: brand-accent-001 type: do rule: "Reserve `rgb(57, 140, 203)` for primary CTAs and brand-mark signals only" why: "Single chromatic assertion device — overuse dilutes meaning" test: "querySelectorAll('[style*=\"rgb(57, 140, 203)\"]').length <= 3 per fold" ``` ## 9. Responsive Behavior ### Breakpoints | Name | Width | Key Changes | |------|-------|-------------| | Mobile | 400px | Single column, compact spacing | | Mobile | 460px | Single column, compact spacing | | Mobile Large | 640px | Expanded mobile layout | | Tablet | 768px | Multi-column grids begin | | Tablet | 996px | Multi-column grids begin | | Desktop | 1280px | Full feature layout | | Large Desktop | 1440px | Maximum content width | ### Token Diff — Desktop vs Mobile | Element | Property | Desktop | Mobile | |---------|----------|---------|--------| | heading | font-size | `48px` | `24px` | | heading | line-height | `48px` | `30px` | | heading | letter-spacing | `-1.2px` | `-0.6px` | | button | width | `auto` | `30px` | ### Collapsing Strategy - Headlines: 48px → 24px 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: 0px 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): - **Hero CTAs:** 3 on desktop → 1 on mobile (secondary CTAs dropped on small screens). - **Navigation collapses to hamburger** — 6 links visible on desktop, 1 on mobile (the rest hide behind a menu toggle). - **Card grid: 4-up → 1-up** — cards stack as viewport narrows, becoming a vertical list on mobile. - **Footer columns collapse:** 3 columns (desktop) → 1 column (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.* - **Mesh gradients** — 1 multi-stop organic color field(s) as background atmosphere. > **Motion fingerprint**: mesh gradients ## 9b. Visual Tone & Photography **Tone:** Mixed photography + illustration A balanced mix of photographic content and vector graphics. Photos likely carry product/lifestyle context while SVG handles icons, logos, and decorative accents. **Canonical Brand Image (OG):** - https://og-image.trpc.io/api/landing?cache-buster=26 *This is the image shown when the site is shared on social media — represents the brand visual essence.* **Hero Image (above-fold dominant visual):** - Aspect: 1:1 (square / portrait) - Rendered size: 80×80px - Alt text: "Greptile" - *Use this aspect ratio + composition for your clone's hero — mimicking the proportion preserves the visual hierarchy.* **Aspect Ratio Distribution:** - Landscape (1.15–2.3): 0 (0%) - Portrait (<0.87): 0 (0%) - Square (0.87–1.15): 6 (100%) **Media Format Mix:** - PNG: 1 (logos, transparent UI elements, mockups) **Average rendered image size:** 76×76px **Above-fold image count:** 0 / 6 **Decorative Patterns Detected:** - 3 multi-stop linear gradients (mesh-like, 3+ color stops) — the brand leans on rich color transitions for visual depth - 1 radial gradient — circular color blooms used for spotlight/glow effects - 26 background patterns (non-photo url() backgrounds) — textures/illustrations as backdrops **Clone instruction for decorative work:** This is a gradient-rich design — invest in multi-stop CSS gradients (3+ color stops), not solid backgrounds. **Imagery Guidance for clones:** - Mix photography and illustration intentionally: photos for product/context, vectors for icons + decorative accents. - Respect the format split — replacing JPGs with illustrations (or vice versa) will shift the brand tone. ## 10. Agent Prompt Guide ### Quick Reference - Background: Pure White (`#ffffff`) - Primary text: Near-Black (`#1c1e21`) - Accent: Steel Blue (`#398ccb`) - Border: Cool Gray (`#969faf`) - Font: ui-sans-serif - Body: 16px weight 400 ### Example Component Prompts - "Create a hero section on Pure White background (#ffffff). Headline at 48px ui-sans-serif weight 800, line-height 1, letter-spacing -1.2px, color #1c1e21." - "Create the primary CTA button: `#398ccb` background, `#ffffff` text, 8px border-radius, 8px 16px padding, 700 weight, ui-sans-serif font." - "Build navigation: sticky on `#ffffff`. ui-sans-serif 16px weight 400 for links." ### Iteration Guide 1. **Canvas**: Set the light canvas to Pure White (`#ffffff`) — every component is composited against this exact base. 2. **Typography**: All type in ui-sans-serif, weight range 300–800. Never exceed 800 — heavier weights break the brand's tonal restraint. 3. **Accent**: Steel Blue (`#398ccb`) is the sole interactive color. On hover → Lavender (`#c7d2fe`). Use CSS transitions, not opacity/brightness filters. 4. **Motion**: All transitions use `cubic-bezier(0.08,0.52,0.52,1)`. Timing: 200ms for micro-interactions, 200ms 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-surface-1: #ffffff; --ca-surface-2: #f4f4f5; --ca-ink-muted: #1c1e21; --ca-ink-subtle: #474748; --ca-primary: #398ccb; --ca-on-primary: #111111; --ca-hairline: #969faf; --ca-semantic-error: #fd9c9f; --ca-semantic-success: #008b00; --ca-semantic-warning: #e6a700; --ca-semantic-info: #87d8f2; } /* Typography */ :root { --ca-font-primary: "Inter", system-ui, sans-serif; --ca-text-display: 48px; --ca-text-heading: 48px; --ca-text-body: 16px; --ca-text-small: 14px; --ca-text-button: 18px; } /* 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: 60px; --ca-radius-none: 0px; --ca-radius-xs: 4px; --ca-radius-sm: 8px; --ca-radius-md: 12px; --ca-radius-lg: 16px; --ca-radius-xl: 9999px; --ca-radius-full: 9999px; } ``` ## 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: div height: 7865px width: full-bleed layout: flex-column justify=normal children: 4 vertical-padding: ~32px - section: header tag: header classes: ["mx-auto", "pt-12", "text-center", "lg:pt-16"] height: 1224px width: 1272px layout: block children: 3 vertical-padding: ~48px padding: "96px 0px 0px" - section: feature-section tag: main classes: ["container", "mx-auto", "space-y-28", "px-6"] height: 7529px width: 1320px layout: block children: 8 vertical-padding: ~72px (generous) padding: "0px 24px" - section: feature-section tag: div classes: ["main-wrapper", "mainWrapper_gJqL"] height: 7529px width: full-bleed layout: flex-column justify=normal children: 1 bg-treatment: radial-gradient - section: content-section tag: section height: 352px width: 1272px layout: block children: 1 - section: feature-section tag: section height: 228px width: 1272px layout: block children: 2 - section: feature-section tag: section classes: ["py-4", "md:py-8"] height: 1313px width: 1272px layout: block children: 2 vertical-padding: ~32px padding: "32px 0px" - section: content-section tag: div classes: ["code-container"] height: 521px width: 610px layout: block children: 1 padding: "16px 0px" - section: unknown tag: div classes: ["code-container"] height: 176px width: 610px layout: block children: 1 padding: "16px 0px" - section: unknown tag: div classes: ["code-container"] height: 248px width: 610px layout: block children: 1 padding: "16px 0px" - section: feature-section tag: section classes: ["mx-auto", "hidden", "max-w-[1600px]", "md:block"] height: 1036px width: 1272px layout: block children: 3 - section: feature-section tag: section classes: ["mx-auto", "max-w-[80ch]", "px-6", "md:px-0"] height: 224px width: 814px layout: block children: 2 - section: feature-section tag: section height: 1384px width: 1272px layout: block children: 2 - section: feature-section tag: section classes: ["pb-12"] height: 984px width: 1272px layout: block children: 2 vertical-padding: ~24px padding: "0px 0px 48px" - section: footer tag: footer classes: ["footer"] height: 276px width: full-bleed layout: block children: 1 bg: "rgb(245, 246, 247)" vertical-padding: ~32px padding: "32px" - section: logo-strip tag: div classes: ["container", "container-fluid"] height: 212px width: 1320px layout: block children: 2 padding: "0px 16px" ``` **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: - "SUPPORTED BY" sub-headings: - "Automatic typesafety" - "Alex/KATT" ctas: - "11.x" - "Search K" - "Star 40,311" - "Quickstart" - "Copy" - "Node.js" - "Use this template" navigation: - "tRPC" - "Star 40,311" - "22 more" - "Docs" - "Quickstart" - "Awesome tRPC Collection" - "Using Next.js" - "11.x" footer-links: - "Docs" - "GitHub" ``` **Agent rule**: reuse these exact strings when generating UI. Do NOT translate or rephrase — brand voice is preserved through the original wording. ## 15. Asset Inventory (Image Roles & Ratios) *Image inventory classified by role and aspect ratio. When reproducing the site, allocate this number of assets per role.* ```yaml assets: logo: count: 13 avg-ratio: 3.37 common-aspect: "~16:6 banner" sample-alts: - "Cal.com" - "Google" - "Netflix" thumbnail: count: 19 avg-ratio: 1.00 common-aspect: "~1:1 square" sample-alts: - "tRPC logo" - "Greptile" - "CodeRabbit" ``` **Agent rule**: when generating placeholder images, match these counts and aspect ratios. Use neutral placeholder backgrounds for `product` (e.g. `#f5f5f5`), full-color photography hints for `hero` and `editorial`. ## 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 `0px` · radius `0px` · weight `500`_ **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** 3 · **docs** 5 · **social** 24 · **footer** 18 · **other** 10 **Projects / case studies detected** (clustered by URL + featured image): *Trpc* — medium confidence, 4 items: | Title | Featured image | Link | |---|---|---| | Star 40,311 | — | https://github.com/trpc/trpc/stargazers | | Use this template | — | https://github.com/trpc/examples-minimal/generate | | GitHub | — | https://github.com/trpc/trpc/tree/main | | Trpc | — | https://github.com/trpc/trpc | **Signals:** 28/60 links carry a featured image · dominant link roles: footer-link (24), content-card (21), inline-link (9). --- ## Extraction Completeness: 84/100 (B) | Category | Score | Max | Detail | |----------|-------|-----|--------| | Colors & Palette | 25 | 25 | 21 named colors | | Typography | 20 | 20 | 8 roles defined | | Components | 12 | 20 | 3 specs extracted | | Motion & Interaction | 12 | 15 | Keyframes | | CSS Custom Properties | 10 | 10 | 377 vars | | Responsive Breakpoints | 5 | 5 | 7 breakpoints | | Variable Fonts | 0 | 5 | None detected | ## 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 (Inter, codicon)** — 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. - **1 parasitic shadow(s) detected** — colored box-shadows (not near-black) found in allShadows. These likely originate from browser extensions or third-party injected widgets (e.g. Grammarly, chat overlays), not from the site's own design system. Discard them when building. | Category | What's missing | Fallback strategy | |----------|----------------|-------------------| | **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 | 377 CSS vars (semantic naming requires ≥20 for high) | | §3 Typography | High | 8 typography roles inferred | | §4 Components | Medium | 3 component variants captured | | §7 Motion | High | Keyframes + transitions | | §8 Do's/Don'ts | High | 25 rules generated; design-decisions.json has evidence per rule | | §9 Responsive | High | 7 breakpoints detected | | §9b Photography | High | 6 images, hero present | ## 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 `