MozaikaDesign system

LangChain — Design System

dark · modern · medium · custom · confidence 90% · deep decode

The full decoded design system for LangChain: color roles, type scale, spacing, radii and paste-ready DESIGN.md / Tailwind / CSS exports.

Open in Mozaika →

This is a static, crawlable rendering for search & AI engines. The interactive version — filters, live decode console, copy & export — is at https://mozaika.design/ds/langchain.

Tokens

LangChain's decoded design system: background #030710, text #E5F4FF, accent #7FC8FF, link #7FC8FF, primary #CCE9FF; type scale h1 63px / h2 54px / body 20.25px; 4px spacing base; 18px base radius. The single interactive/action color is #E5F4FF — used only on interactive or must-notice elements (buttons, links, key highlights), never on large fills.

Color roles

RoleValue
bg#030710
surface#10151E
border#242A33
text#E5F4FF
text_muted#8F99A4
primary#CCE9FF
accent#7FC8FF
link#7FC8FF
secondary#E5F4FF
button_bg#E5F4FF
button_text#030710

Using these colors

Typography

Spacing

Radii

Shadows (elevation)

Motion

Micro-interactions run at 300ms (dominant) with ease.

Native design tokens

TokenValue
--colors--violet--violet-100#f8f7ff
--colors--green--green-400#1d3d3c
--dark--button-text#1d3d3c
--colors--blue--blue-500#043e5d
--colors--green--green-300#8b9c9c
--colors--violet--violet-400#beb4fd
--nav--button-text#1d3d3c
--colors--violet--violet-300#cfc8fe
--red--button-text#772730
--colors--green--green-100#e9ecec

…and 44 more measured on the page.

Button states (measured)

Layout (measured)

Motion choreography (measured)

Load order: a.swiper-slide×10 → h1.t-heading-1-rg → a.banner-link → a.banner-link → div.embed-icon×9 → a.navbar2_logo-link

Responsive (measured)

Per-section tokens (13)

Export: DESIGN.md

# LangChain — Design System

> dark, modern, medium, custom — deep decode (measured live)

## Colors

| Role | Value |
|------|-------|
| bg | `#030710` |
| surface | `#10151E` |
| border | `#242A33` |
| text | `#E5F4FF` |
| text_muted | `#8F99A4` |
| primary | `#CCE9FF` |
| accent | `#7FC8FF` |
| link | `#7FC8FF` |
| secondary | `#E5F4FF` |
| button_bg | `#E5F4FF` |
| button_text | `#030710` |

**Using these colors**

- **Action color** `#E5F4FF` — the single interactive color; it appears only on things you click or must notice (buttons, key highlights), never on large fills or backgrounds.
- `accent`, `link` are all `#7FC8FF` — one role, not several.
- `secondary`, `button_bg` are all `#E5F4FF` — one role, not several (your action color).
- **accent** `#7FC8FF` — accent for emphasis — keep it rare on the page.
- **primary** `#CCE9FF` — a neutral UI color (chips, tags, icon fills, chrome), not the action color (action = #E5F4FF).
- **Page coverage** (full-page screenshot pixels): `#030710` 85.1% · `#398BDC` 7% · `#0C1521` 5.3% · `#234465` 2.6%

## Typography

- Heading: **Twklausanne** _(free fallback: Newsreader)_
- Body: **Aeonik** _(free fallback: Space Grotesk)_

| Role | Size / weight · line-height · tracking |
|------|------------------------------------------|
| hero | 56px / 300 · lh 62px · tracking -1.68px |
| h2 | 32px / 300 · lh 35px · tracking -0.96px |
| body | 16px / 300 · lh 22px |
| small | 14px / 400 · lh 14px |

- Weight ladder: 300 · 400 — use these exact measured weights, not the 400/600 defaults.

> **Fonts —** Twklausanne may be proprietary — safe free fallback: Newsreader (Google Fonts). Aeonik is proprietary — closest free match: Space Grotesk (Google). Load Space Grotesk; keep Aeonik first so licensed users still get it.

## Spacing
- base unit: 4px (inferred from the measured scale)
- measured scale: 8px, 10px, 12px, 16px, 18px, 20px, 22px, 24px, 32px, 43px — snap all gaps/padding to these

## Radius
- base: 18px
- button: 7px
- card: 6px

## Buttons

| Button | Fill / text | Border | Radius | Padding | Font | Shadow |
|--------|-------------|--------|--------|---------|------|--------|
| primary | `#E5F4FF` / `#030710` | none | 6px | 12px 18px 12px 18px | 400 14px | none |
| secondary | `rgba(0, 0, 0, 0)` / `#CCE9FF` | 1px solid rgb(47, 75, 104) | 6px | 12px 18px 12px 18px | 400 14px | none |

**States (measured, not guessed)**

- primary hover: box-shadow `rgba(127, 200, 255, 0.4) 0px 0px 20px 4px`
- primary focus: outline `1px auto rgb(16, 16, 16)`
- secondary hover: box-shadow `rgba(127, 200, 255, 0.3) 0px 0px 20px 2px`
- transition: `all 0.3s ease`

## Shadows (elevation)
- overlay: `rgba(127, 200, 255, 0.5) 0px 0px 32px 0px`

## Motion
- durations: 300ms (dominant) · 200ms · 500ms
- easings: `ease` (dominant) · `ease-out`
- animated properties: opacity

Micro-interactions use the dominant duration + easing; nothing on the page animates slower than the longest duration above — don't invent springier motion.

## Their own tokens (verbatim from :root)

| Token | Value |
|-------|-------|
| `--colors--violet--violet-100` | `#f8f7ff` |
| `--colors--green--green-400` | `#1d3d3c` |
| `--dark--button-text` | `#1d3d3c` |
| `--colors--blue--blue-500` | `#043e5d` |
| `--colors--green--green-300` | `#8b9c9c` |
| `--colors--violet--violet-400` | `#beb4fd` |
| `--nav--button-text` | `#1d3d3c` |
| `--colors--violet--violet-300` | `#cfc8fe` |
| `--red--button-text` | `#772730` |
| `--colors--green--green-100` | `#e9ecec` |
| `--colors--red--red-400` | `#772730` |
| `--colors--blue--blue-400` | `#076597` |

_…and 42 more measured on the page._

Prefer these names when extending their system — it's the brand's actual vocabulary.

## Layout (measured)
- container max 1416px
- nav: 72px sticky

| Section (y) | Height | Cols | Gap | Pad y | Split |
|---|---|---|---|---|---|
| 126 | 434 | — | — | 0/0 | — |
| 560 | 1302 | — | — | 0/0 | — |

## Motion choreography (measured)
Load order: `a.swiper-slide`×10 @0ms → `h1.t-heading-1-rg` @0ms → `a.banner-link` @256ms → `a.banner-link` @256ms → `div.embed-icon`×9 @256ms → `a.navbar2_logo-link` @256ms

Rebuild the timeline, not just the durations — order, delays and staggers above are the choreography.

## Responsive (measured)
- breakpoints: 479px · 767px · 992px
- mobile (390px): hero 36px · body 16px · nav: hamburger

## How to apply
Paste the Tailwind `@theme` (or CSS variables) as your base, then build each
section to its spec — verify every color, radius, and font against these tokens.
Hover/focus states, shadows and motion timings above are measured from the live page — match them exactly, don't re-guess them.

---

> **Decoded with Mozaika** — measured live, not guessed. Full decoded design system + one-command install: mozaika.design/ds/langchain

Export: Tailwind v4 (@theme)

@theme {
  /* action color #E5F4FF — the one interactive color; buttons/links/emphasis only, never large fills. */
  --color-bg: #030710;
  --color-surface: #10151E;
  --color-border: #242A33;
  --color-text: #E5F4FF;
  --color-text-muted: #8F99A4;
  --color-primary: #CCE9FF;  /* a neutral UI color (chips, tags, icon fills, chrome), not the action color (action = #E5F4FF). */
  --color-accent: #7FC8FF;  /* accent for emphasis — keep it rare on the page. */
  --color-link: #7FC8FF;  /* inline text links and link-styled controls. */
  --color-secondary: #E5F4FF;  /* same color as the action (see accent). */
  --color-button-bg: #E5F4FF;  /* primary-button fill — the main call-to-action color. */
  --color-button-text: #030710;
  /* fonts: Twklausanne may be proprietary — safe free fallback: Newsreader (Google Fonts). Aeonik is proprietary — closest free match: Space Grotesk (Google). Load Space Grotesk; keep Aeonik first so licensed users still get it. */
  --font-heading: "Twklausanne", "Newsreader", system-ui, -apple-system, 'Segoe UI', sans-serif;
  --font-body: "Aeonik", "Space Grotesk", system-ui, -apple-system, 'Segoe UI', sans-serif;
  /* measured weights: 300, 400 — use these, not 400/600 */
  --text-hero: 56px; --font-weight-hero: 300; --leading-hero: 62px; --tracking-hero: -1.68px;
  --text-h2: 32px; --font-weight-h2: 300; --leading-h2: 35px; --tracking-h2: -0.96px;
  --text-body: 16px; --font-weight-body: 300; --leading-body: 22px;
  --text-small: 14px; --font-weight-small: 400; --leading-small: 14px;
  --radius-base: 18px;
  --radius-button: 7px;
  --radius-card: 6px;
  --shadow-overlay: rgba(127, 200, 255, 0.5) 0px 0px 32px 0px;
  --outline-focus: 1px auto rgb(16, 16, 16);  /* measured focus ring */
  --ease-brand: ease;
  --duration-fast: 200ms;  /* use: duration-[var(--duration-fast)] */
  --duration-base: 300ms;
  --duration-slow: 500ms;
  --spacing: 4px;  /* measured base — drives the p-*/gap-* scale. steps seen on the page: 8, 10, 12, 16, 18, 20, 22, 24, 32, 43px */
}

Export: CSS variables

:root {
  /* action color #E5F4FF — the one interactive color; buttons/links/emphasis only, never large fills. */
  --bg: #030710;
  --surface: #10151E;
  --border: #242A33;
  --text: #E5F4FF;
  --text-muted: #8F99A4;
  --primary: #CCE9FF;  /* a neutral UI color (chips, tags, icon fills, chrome), not the action color (action = #E5F4FF). */
  --accent: #7FC8FF;  /* accent for emphasis — keep it rare on the page. */
  --link: #7FC8FF;  /* inline text links and link-styled controls. */
  --secondary: #E5F4FF;  /* same color as the action (see accent). */
  --button-bg: #E5F4FF;  /* primary-button fill — the main call-to-action color. */
  --button-text: #030710;
  --font-heading: "Twklausanne", "Newsreader", system-ui, -apple-system, 'Segoe UI', sans-serif;
  --font-body: "Aeonik", "Space Grotesk", system-ui, -apple-system, 'Segoe UI', sans-serif;
  --text-hero: 56px; --weight-hero: 300; --leading-hero: 62px; --tracking-hero: -1.68px;
  --text-h2: 32px; --weight-h2: 300; --leading-h2: 35px; --tracking-h2: -0.96px;
  --text-body: 16px; --weight-body: 300; --leading-body: 22px;
  --text-small: 14px; --weight-small: 400; --leading-small: 14px;
  --radius: 18px;
  --radius-button: 7px;
  --radius-card: 6px;
  --shadow-overlay: rgba(127, 200, 255, 0.5) 0px 0px 32px 0px;
  --focus-ring: 1px auto rgb(16, 16, 16);
  --ease: ease;
  --duration-fast: 200ms;
  --duration-base: 300ms;
  --duration-slow: 500ms;
}

/* their own tokens, verbatim from the site's :root */
:root {
  --colors--violet--violet-100: #f8f7ff;
  --colors--green--green-400: #1d3d3c;
  --dark--button-text: #1d3d3c;
  --colors--blue--blue-500: #043e5d;
  --colors--green--green-300: #8b9c9c;
  --colors--violet--violet-400: #beb4fd;
  --nav--button-text: #1d3d3c;
  --colors--violet--violet-300: #cfc8fe;
  --red--button-text: #772730;
  --colors--green--green-100: #e9ecec;
  --colors--red--red-400: #772730;
  --colors--blue--blue-400: #076597;
}
/* fonts: Twklausanne may be proprietary — safe free fallback: Newsreader (Google Fonts). Aeonik is proprietary — closest free match: Space Grotesk (Google). Load Space Grotesk; keep Aeonik first so licensed users still get it. */