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CSS Custom Properties Theming

intermediatecss~15min

Background

Custom properties enable dynamic theming without preprocessor recompilation.

Problem

Create a theming system using CSS custom properties that can be updated at runtime.

Input

Theme variable definitions

Output

Dynamic themed UI

Sample tests

Sample 1

Input: data-theme="dark"
Expected: dark theme applied

Your solution

Learning objective

Learn CSS custom properties and dynamic theming