CSS Variables Theme Builder
Define design tokens and export them as CSS custom properties.
Design tokens as CSS variables
A theme built on CSS custom properties is easy to maintain and re-skin — change a token in one place and it updates everywhere. This builder lets you define your tokens (colors, spacing, radii) and exports them as a clean :root block.
Centralizing values as variables is the foundation of a scalable design system and effortless dark-mode theming. Define your tokens, and copy the generated custom properties straight into your stylesheet as the single source of truth.
Copy-ready tokens
Custom properties defined on :root cascade everywhere, so re-skinning is a matter of changing tokens in one place. Built in your browser, nothing uploaded.
Frequently asked questions
How do I enter the tokens?
One token per line as "name: value", such as "brand: #0ea5e9" or "radius: 12px". Each line becomes a --name: value; custom property inside a :root block, with spaces in names turned into hyphens.
Which token names does the preview use?
brand colors the heading, surface sets the card background, radius rounds its corners, and space sets its padding. Other tokens are exported but not previewed.
How do I use the variables in my CSS?
Reference them with var(), for example color: var(--brand). Redefine the same names inside a [data-theme="dark"] or prefers-color-scheme block to switch themes without touching component styles.
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