On Running — decoded design system

on.com · light · modern · custom · deep decode — measured live

On Running'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.

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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/on.com.

Decoded design system

On Running's decoded design system: background #FFFFFF, text #000000, accent #2F7EFE, link #0000EE, primary #ED0000; type scale h1 50px / h2 33px / body 24px; 4px spacing base; 4px base radius. The single interactive/action color is #000000 — used only on interactive or must-notice elements (buttons, links, key highlights), never on large fills.

Color roles

Using these colors

• Action color #000000 — the single interactive color; only on things you click or must notice, never large fills.
• link, secondary are all #0000EE — one role, not several (the action color).
• accent #2F7EFE — accent for emphasis — keep it rare on the page.
• primary #ED0000 — a brand color — but the call-to-action uses #000000, not this.

Typography

• Heading: Noto Sans JP
• Body: Noto Sans JP
• Mono: On Semi Mono
• h1: 50px
• h2: 33px
• body: 24px

Spacing

• base unit: 4px
• scale: 2px, 4px, 8px, 12px, 16px, 20px, 24px, 32px, 40px, 48px

Radii

• base: 4px
• button: 40px

Shadows (elevation)

• subtle: rgba(0, 0, 0, 0.05) 0px 0px 0.5px 0px, rgba(0, 0, 0, 0.1) 0px 2px 4px 0px
• card: rgba(0, 0, 0, 0.1) -14px 0px 16px 0px

Motion

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

• durations: 300ms · 200ms · 500ms
• easings: ease · cubic-bezier(0.87, 0, 0.13, 1)
• animated properties: background, transform, color, opacity

Native design tokens

Button states (measured)

• primary hover: border 1px solid rgb(51, 51, 51) · background #333333

Layout (measured)

• container max-width: 650px
• nav: 90px absolute
• common grid: 12 columns

Motion choreography (measured)

Load order: span._container_bdd6m_27×12 → span._container_bdd6m_27 → div._closeButtonContainer_1v → div.onetrust-pc-dark-filter → div.otFloatingRounded → div._logoSection_1xk6q_201

Responsive (measured)

• breakpoints: 768px · 1024px · 1440px
• mobile (390px): nav inline

Install it

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

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

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

Export: DESIGN.md

# On Running — Design System

> light, modern, high, custom — deep decode (measured live)

## Colors

| Role | Value |
|------|-------|
| bg | `#FFFFFF` |
| surface | `#EFEFEF` |
| border | `#D8D8D8` |
| text | `#000000` |
| text_muted | `#606060` |
| primary | `#ED0000` |
| accent | `#2F7EFE` |
| link | `#0000EE` |
| secondary | `#0000EE` |
| button_bg | `#000000` |
| button_text | `#FFFFFF` |

**Using these colors**

- **Action color** `#000000` — the single interactive color; it appears only on things you click or must notice (buttons, key highlights), never on large fills or backgrounds.
- `link`, `secondary` are all `#0000EE` — one role, not several.
- **accent** `#2F7EFE` — accent for emphasis — keep it rare on the page.
- **primary** `#ED0000` — a brand color — but the call-to-action uses #000000, not this.
- **Page coverage** (full-page screenshot pixels): `#2C2D2C` 28.8% · `#7F7F7F` 24.9% · `#FFFFFF` 22% · `#575D58` 9.9%

## Typography

- Heading: **Noto Sans JP** _(free fallback: Newsreader)_
- Body: **Noto Sans JP** _(free fallback: Newsreader)_
- Mono: **On Semi Mono** _(measured)_

| Role | Size / weight · line-height · tracking |
|------|------------------------------------------|
| hero | 50px / 700 · lh 60px · tracking -0.5px |
| h2 | 33px / 600 · lh 40px |
| h3 | 31px / 400 · lh 40px |
| body | 24px / 700 · lh 29px |
| small | 20px / 700 · lh 30px |
| eyebrow | 12px / 500 · tracking 1.44px |

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

> **Fonts —** Noto Sans JP may be proprietary — safe free fallback: Newsreader (Google Fonts).

## Spacing
- base unit: 4px (inferred from the measured scale)
- measured scale: 2px, 4px, 8px, 12px, 16px, 20px, 24px, 32px, 40px, 48px — snap all gaps/padding to these
- section rhythm: 64px top/bottom padding per section (measured)

## Radius
- base: 4px
- button: 40px
- card: 4px
- sharp: 2px

## Buttons

| Button | Fill / text | Border | Radius | Padding | Font | Shadow |
|--------|-------------|--------|--------|---------|------|--------|
| primary | `#000000` / `#FFFFFF` | 1px solid rgb(0, 0, 0) | 40px | 0px 24px 0px 24px | 500 16px | none |
| secondary | `#FFFFFF` / `#000000` | 1px solid rgb(255, 255, 255) | 40px | 0px 24px 0px 24px | 500 16px | none |

**States (measured, not guessed)**

- primary hover: border `1px solid rgb(51, 51, 51)` · background `#333333`

## Shadows (elevation)
- subtle: `rgba(0, 0, 0, 0.05) 0px 0px 0.5px 0px, rgba(0, 0, 0, 0.1) 0px 2px 4px 0px`
- card: `rgba(0, 0, 0, 0.1) -14px 0px 16px 0px`

## Motion
- durations: 300ms (dominant) · 200ms · 500ms
- easings: `ease` (dominant) · `cubic-bezier(0.87, 0, 0.13, 1)`
- animated properties: background, transform, color, 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 |
|-------|-------|
| `--f-spinner-color-1` | `#0000001a` |
| `--f-spinner-color-2` | `#11181ccc` |
| `--sb-width` | `0px` |
| `--ticker-height` | `3rem` |
| `--adjust-banner-height` | `0px` |
| `--f-spinner-width` | `36px` |
| `--f-spinner-height` | `36px` |

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

## Layout (measured)
- container max 650px · common grid: 12-col
- nav: 90px absolute

| Section (y) | Height | Cols | Gap | Pad y | Split |
|---|---|---|---|---|---|
| 981 | 727 | 12 | — | 0/0 | — |
| 1789 | 685 | 12 | — | 0/0 | — |
| 2555 | 572 | 12 | — | 0/0 | — |
| 3208 | 748 | — | — | 0/0 | — |
| 4037 | 1618 | 12 | — | 0/0 | — |
| 4119 | 610 | 4 | 24 | 0/0 | — |

## Motion choreography (measured)
Load order: `span._container_bdd6m_27`×12 @0ms → `span._container_bdd6m_27` @0ms → `div._closeButtonContainer_1v` @401ms → `div.onetrust-pc-dark-filter` @1303ms → `div.otFloatingRounded` @1303ms → `div._logoSection_1xk6q_201` @2190ms
- `span._container_bdd6m_27` — opacity 0.6→1 — 400ms ease
- `div._navigationItemListSecti` — opacity 0→1 — 250ms ease (delay 100ms)
- `div._logoSection_1xk6q_201` — opacity 0→1 — 250ms ease (delay 100ms)
- `div._closeButtonContainer_1v` — opacity 1→0 — 200ms ease-in (delay 400ms)

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

## Components (measured)
- link: #000000 · no underline
- disabled: bg #FFFFFF · text #000000

## Responsive (measured)
- breakpoints: 768px · 1024px · 1440px
- mobile (390px): 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 On Running's publicly-visible CSS (colors, fonts, spacing, motion) — not affiliated with on.com. No screenshots stored. Removal requests: hello@mozaika.design.