Theming Websites with CSS

Techniques for building switchable themes with custom properties, design tokens, and modern colour functions.

Content tagged theming

• Tutorial:One-Line Theme-Aware Colors with light-dark()

  A single declaration per color, resolved automatically for both light and dark mode.

  The light-dark() CSS function collapses a light value and a dark value into one declaration, resolved by color-scheme — no duplicate custom properties, no @media (prefers-color-scheme) block per themed property.