diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 1e19c57..bd42b2f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -33,5 +33,15 @@ jobs:
       - name: Install dependencies
         run: pnpm install --frozen-lockfile
 
+      - name: Validate design tokens
+        run: pnpm tokens:validate
+
+      - name: Check generated design tokens
+        run: |
+          test -f design-tokens/generated/astrea.tokens.css
+          test -f design-tokens/generated/astrea_tokens.dart
+          pnpm tokens:generate
+          git diff --exit-code -- design-tokens/generated
+
       - name: Build handbook
         run: pnpm build
diff --git a/design-tokens/README.md b/design-tokens/README.md
new file mode 100644
index 0000000..e706396
--- /dev/null
+++ b/design-tokens/README.md
@@ -0,0 +1,61 @@
+# Astrea design tokens
+
+`tokens.json` is the platform-agnostic representation of the foundations from the `10 - Foundations` page in the Astrea Figma file.
+
+The `generated/astrea.tokens.css` and `generated/astrea_tokens.dart` files are produced by:
+
+```bash
+node design-tokens/generate.mjs
+```
+
+Contrast-pair validation is run with:
+
+```bash
+node design-tokens/validate.mjs
+```
+
+The applications consume these outputs in their own repositories:
+
+- `app-web/src/styles/tokens.css`
+- `app-mobile/lib/core/design_tokens.dart`
+
+Synchronization must regenerate both files. Values must not be edited directly in generated outputs.
+
+## Update procedure
+
+When a foundation changes in Figma:
+
+1. Update `tokens.json` with the approved values from `10 - Foundations`.
+2. Run `pnpm tokens:validate`.
+3. Run `pnpm tokens:generate`.
+4. Copy `generated/astrea.tokens.css` to `app-web/src/styles/tokens.css`.
+5. Copy `generated/astrea_tokens.dart` to `app-mobile/lib/core/design_tokens.dart`.
+6. Verify that the outputs match the synchronized files.
+7. Run the local validations for all three repositories.
+8. Open the pull requests linked to the same issue.
+
+The `app-web` and `app-mobile` pull requests must state the source used in their description:
+
+```text
+Design tokens source: docs@<commit-or-tag>
+```
+
+The commit or tag identifies the version of `tokens.json` used to generate the outputs.
+
+## Usage rules
+
+- `color/border` is reserved for separators and decorative borders.
+- `color/border-strong` is used for fields, focus states, and interactive components.
+- `color/primary` and `color/accent` are used as backgrounds.
+- `color/primary-strong` and `color/accent-strong` are used for text, icons, and markers.
+- Text must meet a minimum contrast ratio of `4.5:1`.
+- Borders and graphical components must meet a minimum contrast ratio of `3:1`.
+
+## Fonts
+
+The applications bundle the following weights locally:
+
+- Montserrat: `400`, `600`, `700`
+- Inter: `400`, `600`, `700`
+
+The files are distributed under the SIL Open Font License. Each application repository keeps the `OFL.txt` notice with its font files.
diff --git a/design-tokens/generate.mjs b/design-tokens/generate.mjs
new file mode 100644
index 0000000..1250833
--- /dev/null
+++ b/design-tokens/generate.mjs
@@ -0,0 +1,71 @@
+import { readFile, mkdir, writeFile } from 'node:fs/promises';
+import { dirname, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const root = dirname(fileURLToPath(import.meta.url));
+const tokens = JSON.parse(await readFile(resolve(root, 'tokens.json'), 'utf8'));
+const outputDirectory = resolve(root, 'generated');
+
+const cssName = (name) => name.replace(/[^a-z0-9]+/gi, '-').toLowerCase();
+const dartName = (name, numericPrefix = 'value') => {
+  const identifier = name.replace(/-([a-z])/g, (_, letter) => letter.toUpperCase());
+  return /^[0-9]/.test(identifier) ? `${numericPrefix}${identifier}` : identifier;
+};
+const dartColor = (value) => `0xFF${value.slice(1)}`;
+
+const css = `:root {
+${Object.entries(tokens.color).map(([name, value]) => `  --color-${cssName(name)}: ${value.toLowerCase()};`).join('\n')}
+
+  --font-family-heading: '${tokens.font.heading}', sans-serif;
+  --font-family-body: '${tokens.font.body}', sans-serif;
+${Object.entries(tokens.type).flatMap(([name, value]) => [
+  `  --font-size-${cssName(name)}: ${value['font-size']}px;`,
+  `  --line-height-${cssName(name)}: ${value['line-height']}px;`
+]).join('\n')}
+${Object.entries(tokens.spacing).map(([name, value]) => `  --spacing-${cssName(name)}: ${value}px;`).join('\n')}
+}
+
+.text-petit {
+  font-family: var(--font-family-body);
+  font-size: var(--font-size-petit);
+  line-height: var(--line-height-petit);
+}
+
+.text-petit-gras {
+  font-family: var(--font-family-body);
+  font-size: var(--font-size-petit-gras);
+  font-weight: 700;
+  line-height: var(--line-height-petit-gras);
+}
+
+.text-titre {
+  font-family: var(--font-family-heading);
+  font-weight: 600;
+}
+
+.text-corps {
+  font-family: var(--font-family-body);
+}
+`;
+
+const dart = `import 'package:flutter/material.dart';
+
+abstract final class AstreaColors {
+${Object.entries(tokens.color).map(([name, value]) => `  static const ${dartName(name)} = Color(${dartColor(value)});`).join('\n')}
+}
+
+abstract final class AstreaTypography {
+  static const heading = '${tokens.font.heading}';
+  static const body = '${tokens.font.body}';
+${Object.entries(tokens.type).map(([name, value]) => `  static const ${dartName(name)}FontSize = ${value['font-size']}.0;
+  static const ${dartName(name)}LineHeight = ${value['line-height']}.0;`).join('\n')}
+}
+
+abstract final class AstreaSpacing {
+${Object.entries(tokens.spacing).map(([name, value]) => `  static const ${dartName(name, 'spacing')} = ${value}.0;`).join('\n')}
+}
+`;
+
+await mkdir(outputDirectory, { recursive: true });
+await writeFile(resolve(outputDirectory, 'astrea.tokens.css'), css);
+await writeFile(resolve(outputDirectory, 'astrea_tokens.dart'), dart);
diff --git a/design-tokens/generated/astrea.tokens.css b/design-tokens/generated/astrea.tokens.css
new file mode 100644
index 0000000..857fc27
--- /dev/null
+++ b/design-tokens/generated/astrea.tokens.css
@@ -0,0 +1,62 @@
+:root {
+  --color-primary: #4caf50;
+  --color-primary-hover: #43a047;
+  --color-primary-strong: #2e7d32;
+  --color-on-primary: #212529;
+  --color-accent: #ff9800;
+  --color-accent-strong: #b34700;
+  --color-on-accent: #212529;
+  --color-tertiary: #2b6cb0;
+  --color-ink: #212529;
+  --color-muted: #5b6560;
+  --color-border: #ddd8ce;
+  --color-border-strong: #7c847f;
+  --color-error: #b3261e;
+  --color-error-border: #b3261e;
+  --color-error-bg: #fdedeb;
+  --color-surface: #ffffff;
+  --color-page: #faf7f2;
+  --color-badge: #e8f5e9;
+  --color-map: #efeae0;
+  --color-brand-gradient-start: #43a047;
+  --color-brand-gradient-end: #ffa726;
+  --color-on-error: #ffffff;
+
+  --font-family-heading: 'Montserrat', sans-serif;
+  --font-family-body: 'Inter', sans-serif;
+  --font-size-petit: 12px;
+  --line-height-petit: 16px;
+  --font-size-petit-gras: 12px;
+  --line-height-petit-gras: 16px;
+  --spacing-12: 12px;
+  --spacing-20: 20px;
+  --spacing-32: 32px;
+  --spacing-40: 40px;
+  --spacing-56: 56px;
+  --spacing-xs: 4px;
+  --spacing-sm: 8px;
+  --spacing-md: 16px;
+  --spacing-lg: 24px;
+}
+
+.text-petit {
+  font-family: var(--font-family-body);
+  font-size: var(--font-size-petit);
+  line-height: var(--line-height-petit);
+}
+
+.text-petit-gras {
+  font-family: var(--font-family-body);
+  font-size: var(--font-size-petit-gras);
+  font-weight: 700;
+  line-height: var(--line-height-petit-gras);
+}
+
+.text-titre {
+  font-family: var(--font-family-heading);
+  font-weight: 600;
+}
+
+.text-corps {
+  font-family: var(--font-family-body);
+}
diff --git a/design-tokens/generated/astrea_tokens.dart b/design-tokens/generated/astrea_tokens.dart
new file mode 100644
index 0000000..27bd237
--- /dev/null
+++ b/design-tokens/generated/astrea_tokens.dart
@@ -0,0 +1,47 @@
+import 'package:flutter/material.dart';
+
+abstract final class AstreaColors {
+  static const primary = Color(0xFF4CAF50);
+  static const primaryHover = Color(0xFF43A047);
+  static const primaryStrong = Color(0xFF2E7D32);
+  static const onPrimary = Color(0xFF212529);
+  static const accent = Color(0xFFFF9800);
+  static const accentStrong = Color(0xFFB34700);
+  static const onAccent = Color(0xFF212529);
+  static const tertiary = Color(0xFF2B6CB0);
+  static const ink = Color(0xFF212529);
+  static const muted = Color(0xFF5B6560);
+  static const border = Color(0xFFDDD8CE);
+  static const borderStrong = Color(0xFF7C847F);
+  static const error = Color(0xFFB3261E);
+  static const errorBorder = Color(0xFFB3261E);
+  static const errorBg = Color(0xFFFDEDEB);
+  static const surface = Color(0xFFFFFFFF);
+  static const page = Color(0xFFFAF7F2);
+  static const badge = Color(0xFFE8F5E9);
+  static const map = Color(0xFFEFEAE0);
+  static const brandGradientStart = Color(0xFF43A047);
+  static const brandGradientEnd = Color(0xFFFFA726);
+  static const onError = Color(0xFFFFFFFF);
+}
+
+abstract final class AstreaTypography {
+  static const heading = 'Montserrat';
+  static const body = 'Inter';
+  static const petitFontSize = 12.0;
+  static const petitLineHeight = 16.0;
+  static const petitGrasFontSize = 12.0;
+  static const petitGrasLineHeight = 16.0;
+}
+
+abstract final class AstreaSpacing {
+  static const spacing12 = 12.0;
+  static const spacing20 = 20.0;
+  static const spacing32 = 32.0;
+  static const spacing40 = 40.0;
+  static const spacing56 = 56.0;
+  static const xs = 4.0;
+  static const sm = 8.0;
+  static const md = 16.0;
+  static const lg = 24.0;
+}
diff --git a/design-tokens/tokens.json b/design-tokens/tokens.json
new file mode 100644
index 0000000..e63f757
--- /dev/null
+++ b/design-tokens/tokens.json
@@ -0,0 +1,53 @@
+{
+  "color": {
+    "primary": "#4CAF50",
+    "primary-hover": "#43A047",
+    "primary-strong": "#2E7D32",
+    "on-primary": "#212529",
+    "accent": "#FF9800",
+    "accent-strong": "#B34700",
+    "on-accent": "#212529",
+    "tertiary": "#2B6CB0",
+    "ink": "#212529",
+    "muted": "#5B6560",
+    "border": "#DDD8CE",
+    "border-strong": "#7C847F",
+    "error": "#B3261E",
+    "error-border": "#B3261E",
+    "error-bg": "#FDEDEB",
+    "surface": "#FFFFFF",
+    "page": "#FAF7F2",
+    "badge": "#E8F5E9",
+    "map": "#EFEAE0",
+    "brand-gradient-start": "#43A047",
+    "brand-gradient-end": "#FFA726",
+    "on-error": "#FFFFFF"
+  },
+  "font": {
+    "heading": "Montserrat",
+    "body": "Inter"
+  },
+  "type": {
+    "petit": {
+      "font-family": "body",
+      "font-size": 12,
+      "line-height": 16
+    },
+    "petit-gras": {
+      "font-family": "body",
+      "font-size": 12,
+      "line-height": 16
+    }
+  },
+  "spacing": {
+    "xs": 4,
+    "sm": 8,
+    "md": 16,
+    "lg": 24,
+    "12": 12,
+    "20": 20,
+    "32": 32,
+    "40": 40,
+    "56": 56
+  }
+}
diff --git a/design-tokens/validate.mjs b/design-tokens/validate.mjs
new file mode 100644
index 0000000..156e2bf
--- /dev/null
+++ b/design-tokens/validate.mjs
@@ -0,0 +1,45 @@
+import { readFile } from 'node:fs/promises';
+import { dirname, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const root = dirname(fileURLToPath(import.meta.url));
+const tokens = JSON.parse(await readFile(resolve(root, 'tokens.json'), 'utf8'));
+
+const luminance = (hex) => {
+  const channels = [1, 3, 5].map((offset) => parseInt(hex.slice(offset, offset + 2), 16) / 255);
+  const [r, g, b] = channels.map((channel) =>
+    channel <= 0.04045 ? channel / 12.92 : ((channel + 0.055) / 1.055) ** 2.4,
+  );
+  return 0.2126 * r + 0.7152 * g + 0.0722 * b;
+};
+
+const contrast = (foreground, background) => {
+  const values = [luminance(foreground), luminance(background)].sort((a, b) => b - a);
+  return (values[0] + 0.05) / (values[1] + 0.05);
+};
+
+const color = (name) => tokens.color[name];
+const checks = [
+  ['ink', 'page', 4.5],
+  ['ink', 'surface', 4.5],
+  ['muted', 'page', 4.5],
+  ['muted', 'surface', 4.5],
+  ['primary-strong', 'page', 4.5],
+  ['accent-strong', 'page', 4.5],
+  ['error', 'error-bg', 4.5],
+  ['on-error', 'error', 4.5],
+  ['border-strong', 'surface', 3],
+  ['border-strong', 'page', 3],
+  ['border-strong', 'error-bg', 3],
+];
+
+for (const [foreground, background, threshold] of checks) {
+  const ratio = contrast(color(foreground), color(background));
+  if (ratio < threshold) {
+    throw new Error(
+      `${foreground}/${background}: ${ratio.toFixed(2)}:1 < ${threshold.toFixed(1)}:1`,
+    );
+  }
+}
+
+console.log(`Validated ${checks.length} WCAG token pairs.`);
diff --git a/docs/standards/design-tokens.md b/docs/standards/design-tokens.md
new file mode 100644
index 0000000..1c54c6f
--- /dev/null
+++ b/docs/standards/design-tokens.md
@@ -0,0 +1,49 @@
+---
+title: Design tokens
+sidebar_position: 1
+description: Source and synchronization of Astrea's shared visual foundations.
+---
+
+# Shared design tokens
+
+Astrea's visual foundations are defined in the `10 - Foundations` Figma page and represented in [`design-tokens/tokens.json`](https://github.com/Astrea-EIP/docs/blob/main/design-tokens/tokens.json).
+
+The JSON is the source consumed by the generated outputs:
+
+- CSS for `app-web`
+- Dart for `app-mobile`
+
+Generated outputs must not be edited manually. An update starts in Figma, then updates `tokens.json`, regenerates the outputs, and synchronizes both application repositories.
+
+## Synchronization procedure
+
+After an approved change in Figma:
+
+1. Update `design-tokens/tokens.json`.
+2. Run `pnpm tokens:validate`.
+3. Run `pnpm tokens:generate`.
+4. Synchronize `design-tokens/generated/astrea.tokens.css` with `app-web/src/styles/tokens.css`.
+5. Synchronize `design-tokens/generated/astrea_tokens.dart` with `app-mobile/lib/core/design_tokens.dart`.
+6. Validate all three repositories with their usual local commands.
+7. Open one pull request per repository, all linked to the same issue.
+
+The Web and Mobile pull requests must state the commit or tag of the source used:
+
+```text
+Design tokens source: docs@<commit-or-tag>
+```
+
+The `docs` repository CI validates contrast ratios and fails if generation modifies the versioned outputs.
+
+## Accessibility
+
+- Text must reach `4.5:1`.
+- Components and borders must reach `3:1`.
+- `color/border` is reserved for separators and decorative borders.
+- `color/border-strong` is reserved for fields, focus states, and interactive components.
+
+Figma values that fail when used outside their intended context remain available, but their usage must follow these rules.
+
+## Fonts
+
+`app-web` and `app-mobile` bundle Montserrat and Inter locally, with weights `400`, `600`, and `700`. The files are distributed under the SIL Open Font License; `OFL.txt` notices are kept in each application repository.
diff --git a/package.json b/package.json
index ed56793..be1d209 100644
--- a/package.json
+++ b/package.json
@@ -3,6 +3,8 @@
   "version": "0.0.0",
   "private": true,
   "scripts": {
+    "tokens:generate": "node design-tokens/generate.mjs",
+    "tokens:validate": "node design-tokens/validate.mjs",
     "docusaurus": "docusaurus",
     "start": "docusaurus start",
     "build": "docusaurus build",
diff --git a/sidebars.js b/sidebars.js
index 51b1589..82a019c 100644
--- a/sidebars.js
+++ b/sidebars.js
@@ -52,6 +52,16 @@ const sidebars = {
       },
       items: [{ type: 'autogenerated', dirName: 'operations' }],
     },
+    {
+      type: 'category',
+      label: 'Standards',
+      link: {
+        type: 'generated-index',
+        title: 'Standards',
+        description: 'Shared engineering and design standards.',
+      },
+      items: [{ type: 'autogenerated', dirName: 'standards' }],
+    },
   ],
 };