PostHog — decoded design system

posthog.com · light · modern · tailwind · deep decode — measured live

PostHog's design system, decoded live by Mozaika: measured color roles, type scale, buttons with real hover/focus states, motion and the brand's own tokens.

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/decode/posthog.com.

Decoded design system

PostHog's decoded design system: background #EEEFE9, text #000000, accent #CD8407, link #374151, primary #E1D7C2; type scale h1 36px / h2 24px / body 15px; 4px spacing base; 4px base radius. The single interactive/action color is #CD8407 — used only on interactive or must-notice elements (buttons, links, key highlights), never on large fills.

Color roles

Using these colors

• Action color #CD8407 — the single interactive color; only on things you click or must notice, never large fills.
• primary #E1D7C2, secondary #DDD6C5 are visually the same color (Δ8) — treat as one role (the action color).
• accent, button_bg are all #CD8407 — one role, not several (the action color).
• accent #CD8407 — THE accent / action color — interactive & must-notice only (buttons, links, focus, one key highlight); never large fills or backgrounds. Scarcity is what makes it read as designed.
• link #374151 — inline text links and link-styled controls.

Typography

• Heading: Open Runde
• Body: IBM Plex Sans
• h1: 36px
• h2: 24px
• body: 15px

Spacing

• base unit: 4px
• scale: 2px, 4px, 5px, 6px, 8px, 10px, 12px, 16px, 20px, 24px

Radii

• base: 4px
• button: 6px

Shadows (elevation)

• subtle: rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(0, 0, 0, 0.25) 0px 25px 50px -12px
• card: rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(14, 18, 22, 0.35) 0px 10px 38px -10px, rgba(14, 18, 22, 0.2) 0px 10px 20px -15px

Motion

Micro-interactions run at 150ms (dominant) with cubic-bezier(0.4, 0, 0.2, 1).

• durations: 150ms · 300ms · 3000ms
• easings: cubic-bezier(0.4, 0, 0.2, 1) · linear
• animated properties: color, background-color, border-color, text-decoration-color

Native design tokens

Button states (measured)

• primary focus: outline 1px auto rgb(16, 16, 16)

Layout (measured)

• container max-width: 900px
• common grid: 2 columns

Motion choreography (measured)

Load order: svg.w-[189px]×2 → a.bg-button-shadow×2 → path.segment×3 → g.segment → li.ToastRoot → div.data-[state=active]:anim

Overlay recipe (measured)

dialog panel: #1E1F23 · radius 6px

Themes

dark counterpart: background #1D1F27, text #000000.

Responsive (measured)

• mobile (390px): hero 24px · nav inline

Install it

Drop this measured system into any shadcn/Tailwind project in one command:

npx shadcn add mozaika.design/r/decode/posthog.com

registry item · or query it over MCP: get_design_system("PostHog")

Export: DESIGN.md

# PostHog — Design System

> light, modern, medium, tailwind — deep decode (measured live)

## Colors

| Role | Value |
|------|-------|
| bg | `#EEEFE9` |
| surface | `#DFE0DB` |
| border | `#CACBC6` |
| text | `#000000` |
| text_muted | `#5A5A58` |
| primary | `#E1D7C2` |
| accent | `#CD8407` |
| link | `#374151` |
| secondary | `#DDD6C5` |
| button_bg | `#CD8407` |
| button_text | `#23251D` |

**Using these colors**

- **Action color** `#CD8407` — the single interactive color; it appears only on things you click or must notice (buttons, key highlights), never on large fills or backgrounds.
- `primary` `#E1D7C2`, `secondary` `#DDD6C5` are visually the same color (Δ8) — treat as one role.
- `accent`, `button_bg` are all `#CD8407` — one role, not several (your action color).
- **accent** `#CD8407` — THE accent / action color — interactive & must-notice only (buttons, links, focus, one key highlight); never large fills or backgrounds. Scarcity is what makes it read as designed.
- **link** `#374151` — inline text links and link-styled controls.
- **Page coverage** (full-page screenshot pixels): `#FDFDF8` 50.1% · `#D9D2C1` 40.5% · `#947958` 9.5%

## Typography

- Heading: **Open Runde** _(free fallback: Newsreader)_
- Body: **IBM Plex Sans**

| Role | Size / weight · line-height · tracking |
|------|------------------------------------------|
| hero | 36px / 800 · lh 40px · tracking -0.9px |
| h2 | 24px / 700 · lh 32px · tracking -0.6px |
| h3 | 21px / 700 · lh 30px · tracking -0.54px |
| body | 15px / 400 · lh 23px |
| small | 14px / 600 · lh 20px |

- Weight ladder: 400 · 500 · 600 · 700 · 800 — use these exact measured weights, not the 400/600 defaults.

> **Fonts —** Open Runde may be proprietary — safe free fallback: Newsreader (Google Fonts). IBM Plex Sans — free, on Google.

## Spacing
- base unit: 4px (inferred from the measured scale)
- measured scale: 2px, 4px, 5px, 6px, 8px, 10px, 12px, 16px, 20px, 24px — snap all gaps/padding to these

## Radius
- base: 4px
- button: 6px
- card: 4px
- pill: 9999px

## Buttons

| Button | Fill / text | Border | Radius | Padding | Font | Shadow |
|--------|-------------|--------|--------|---------|------|--------|
| primary | `#CD8407` / `#23251D` | 1px solid rgb(177, 120, 22) | 6px | 0px 0px 0px 0px | 400 16px | none |
| secondary | `rgba(0, 0, 0, 0)` / `#4D4F46` | none | — | 0px 0px 0px 0px | 400 16px | none |

**States (measured, not guessed)**

- primary focus: outline `1px auto rgb(16, 16, 16)`
- transition: `color 0.15s cubic-bezier(0.4, 0, 0.2, 1)`

## Shadows (elevation)
- subtle: `rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(0, 0, 0, 0.25) 0px 25px 50px -12px`
- card: `rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(14, 18, 22, 0.35) 0px 10px 38px -10px, rgba(14, 18, 22, 0.2) 0px 10px 20px -15px`

## Motion
- durations: 150ms (dominant) · 300ms · 3000ms
- easings: `cubic-bezier(0.4, 0, 0.2, 1)` (dominant) · `linear`
- animated properties: color, background-color, border-color, text-decoration-color

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 |
|-------|-------|
| `--viewport-padding` | `25px` |

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

## Layout (measured)
- container max 900px · common grid: 2-col
- nav: 0px

| Section (y) | Height | Cols | Gap | Pad y | Split |
|---|---|---|---|---|---|
| 162 | 714 | — | — | 0/0 | — |
| 3367 | 511 | 2 | 64 | 0/0 | — |

## Motion choreography (measured)
Load order: ``×2 @0ms → `a.bg-button-shadow`×2 @1ms → `path.segment`×3 @46ms → `g.segment` @469ms → `li.ToastRoot` @1493ms → `` @2729ms
- `?` — transform scale(1)→scale(1) — 2000ms · loops
- `a.bg-button-shadow` — transform scale(1)→scale(1) — 3000ms · loops
- overlay dialog (auto-opened): panel #1E1F23 · r 6px · border 1px solid rgb(62, 66, 79) · shadow rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(0, 0, 0, 0) 0px 0px 0px 0px, rgba(14, 18, 22, 0.35) 0px 10px 38px -10px, rgba(14, 18, 22, 0.2) 0px 10px 20px -15px

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

## Components (measured)
- link: #65675E · no underline — hover #4D4F46
- disabled: bg rgba(0, 0, 0, 0) · text #9EA096

## Themes (both measured)
- dark counterpart: bg `#1D1F27` · text `#000000`

## Responsive (measured)
- mobile (390px): hero 24px · body 16px · nav: inline

## 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.

An automated reading of PostHog's publicly-visible CSS (colors, fonts, spacing, motion) — not affiliated with posthog.com. No screenshots stored. Removal requests: hello@mozaika.design.