This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The <length-percentage> CSS data type represents a value that can be either a <length> or a <percentage>.
Refer to the documentation for <length> and <percentage> for details of the individual syntaxes allowed by this type.
<length-percentage> =
<length> |
<percentage>
This example demonstrates several properties that use <length-percentage> values.
<p>You can use percentages and lengths in so many places.</p>
p {
/* length-percentage examples */
width: 75%;
height: 200px;
margin: 3rem;
padding: 1%;
border-radius: 10px 10%;
font-size: 250%;
line-height: 1.5em;
/* length examples */
text-shadow: 1px 1px 1px red;
border: 5px solid red;
letter-spacing: 3px;
/* percentage example */
text-size-adjust: 20%;
}
Where a <length-percentage> is specified as an allowable type, this means that the percentage resolves to a length and therefore can be used in a calc() expression. Therefore, all of the following values are acceptable for width:
width: 200px; width: 20%; width: calc(100% - 200px);
| Specification |
|---|
| CSS Values and Units Module Level 4> # mixed-percentages> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
length-percentage |
1 | 12 | 1 | 3.5 | 1 | 18 | 4 | 10.1 | 1 | 1.0 | 4.4 | 1 |
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https://developer.mozilla.org/en-US/docs/Web/CSS/length-percentage