<dimension>
A general term for any CSS value that combines a number with a unit (like '10px', '2em', or '50%').
Quick example
.box {
/* Examples of different dimension types */
width: 100px; /* length */
font-size: 1.2rem; /* length */
opacity: 0.5; /* number (not a dimension) */
} <dimension> Browser Support
Widely available Since 2015 96% global usage
This feature is well established and works across many devices and browser versions. It has been available across browsers since 2015.
Safe to use without fallbacks.
1+
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