This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The border-right-width CSS property sets the width of the right border of an element.
border-right-width: thick;
border-right-width: 2em;
border-right-width: 4px;
border-right-width: 2ex;
border-right-width: 0;
<section class="default-example" id="default-example">
<div class="transition-all" id="example-element">
This is a box with a border around it.
</div>
</section>
#example-element {
background-color: palegreen;
color: black;
border: 0 solid crimson;
padding: 0.75em;
width: 80%;
height: 100px;
}
/* Keyword values */ border-right-width: thin; border-right-width: medium; border-right-width: thick; /* <length> values */ border-right-width: 10em; border-right-width: 3vmax; border-right-width: 6px; /* Global keywords */ border-right-width: inherit; border-right-width: initial; border-right-width: revert; border-right-width: revert-layer; border-right-width: unset;
<line-width>Defines the width of the border, either as an explicit nonnegative <length> or a keyword. If it's a keyword, it must be one of the following values:
thinmediumthickNote: Because the specification doesn't define the exact thickness denoted by each keyword, the precise result when using one of them is implementation-specific. Nevertheless, they always follow the pattern thin ≤ medium ≤ thick, and the values are constant within a single document.
| Initial value | medium |
|---|---|
| Applies to | all elements. It also applies to ::first-letter. |
| Inherited | no |
| Computed value | the absolute length or 0 if border-right-style is none or hidden
|
| Animation type | a length |
border-right-width =
<line-width>
<line-width> =
<length [0,∞]> |
thin |
medium |
thick
<div>Element 1</div> <div>Element 2</div>
div {
border: 1px solid red;
margin: 1em 0;
}
div:nth-child(1) {
border-right-width: thick;
}
div:nth-child(2) {
border-right-width: 2em;
}
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
border-right-width |
1 | 12 | 1 | 3.5 | 1 | 18 | 4 | 10.1 | 1 | 1.0 | 2.2 | 1 |
border-bottom-width, border-left-width, border-top-width, and border-width.border, border-right, border-right-style, and border-right-color.
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https://developer.mozilla.org/en-US/docs/Web/CSS/border-right-width