accentcolor

Accent-color is a CSS property that controls the color of certain user agent UI elements rendered by the browser, such as checkboxes, radio buttons, and some form-related indicators, to help match a web page to a chosen theme. It affects only those native controls; custom-styled controls created with CSS are not directly affected by this property.

The property accepts two kinds of values: auto and a color. 'Auto' lets the browser pick a color based on the system or theme, while a color value specifies a specific color, using any valid CSS color syntax (named colors, hex, rgb(), hsl(), etc.).

Usage is straightforward: declare accent-color on an element, and the browser’s native controls within that element’s scope will render with the specified color where supported. The exact effect depends on the browser and platform, and not all environments implement it.

Support and status: Accent-color is part of the CSS Color Module and remains experimental in some engines. As of the mid-2020s, major Chromium-based browsers provide support for the property, while Firefox support varies by version and can be incomplete. Developers should provide sensible fallbacks and test across target environments. When designing themes, consider accessibility and ensure sufficient contrast for interactive UI elements, since the accent color can influence the perceived emphasis of controls.