<rem>
A CSS unit that is relative to the font-size of the root element (usually the <html> tag). Unlike 'em', it doesn't change based on the parent's font size, making scaling much more predictable.
Quick example
html {
font-size: 16px;
}
.my-text {
/* This will be exactly 32 pixels regardless of where it's nested */
font-size: 2rem;
}<rem> Browser Support
Newly available Since 2024 86% global usage
Since 2024 this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
Works in all modern browsers. May need a fallback for older browsers.
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