Definition and Usage
The border-bottom-width CSS property sets the width of the bottom border of a box.
- Initialmedium
- Applies toall elements
- Inheritedno
- Mediavisual
- Computed Valuethe absolute length or 0 if border-bottom-style is none or hidden
- Animatableyes, as a length
- Canonical orderthe unique non-ambiguous order defined by the formal grammar
Syntax
Formal syntax: <br-width>
border-bottom-width: 10em /* Any <length> value */ border-bottom-width: 3vmax border-bottom-width: 6px border-bottom-width: thin /* A keyword */ border-bottom-width: medium border-bottom-width: thick border-right-width: inherit
Values
<br-width>Is either a non-negative explicit <length> value or a keyword denoting the thickness of the bottom border. The keyword must be one of the following values:
thin | A thin border | |
medium | A medium border | |
thick | A thick border |
The specification doesn’t precisely define the thickness of each of the keywords, which is therefore implementation specific. Nevertheless, it requests that the thickness does follow the thin ≤ medium ≤ thick inequality and that the values are constant on a single document.
inheritRepresents the calculated value of the border-bottom-width of the parent’s element.
Examples
element {
border-bottom-width: thin;
border-bottom-style: solid;
border-bottom-color: #000;
}
Compatibility
Desktop browsers
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 1.0 | 1.0 (1.0) | 4.0 | 3.5 | 1.0 (85) |
Mobile browsers
| Feature | Android | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | NA | NA | NA | NA | NA |







