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CSS Variables Builder - Free Online CSS Tool | IconVault

Build a CSS custom property theme visually: add variables, edit colors, start from Light, Dark or Pastel presets, preview and export :root CSS. Free.

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CSS Variables Builder

Build CSS custom-property themes, export :root CSS

5 of 5 free uses left

Starter theme

Variables (6)

Add variable

5 of 5 free copies left - everything runs in your browser.

Sample heading

Sample card

Cards, headings and buttons on this page follow your variables live.

Outline card

Edit any value on the left and watch this preview update instantly.

--primary in action

:root {
  --primary: #4f46e5;
  --background: #ffffff;
  --card: #f4f5fb;
  --text: #111827;
  --muted: #6b7280;
  --radius: 12px;
}

About this tool

IconVault's CSS Variables Builder creates CSS custom properties (variables) through a visual theme editor. Add variables with names and values, get a color picker automatically when a value is a color, or start from starter themes like Light, Dark and Pastel and customize from there. A live preview shows your theme applied to sample components, and the tool exports a clean :root block you can drop into any project.

Everything runs 100% in your browser: no sign-up, no uploads, free to use. It is the fastest way to set up a design token palette for colors, spacing, radii and typography, then switch themes by swapping one block of variables. The generated CSS is plain standard custom-property syntax that works in every modern browser.

Frequently asked questions

Popular searches

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