border-top-width property CSS Reference

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Definition and Usage

The border-top-width CSS property sets the width of the top border of a box.

• Initial medium
• Applies to all elements
• Inherited no
• Media visual
• Computed Value the absolute length or 0 if border-top-style is none or hidden
• Animatable yes, as a length
• Canonical order the unique non-ambiguous order defined by the formal grammar

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Syntax

Formal syntax: <br-width>

border-top-width: 10em    /* Any <length> value */
border-top-width: 3vmax
border-top-width: 6px
border-top-width: thin    /* A keyword */
border-top-width: medium
border-top-width: thick
border-top-width: inherit

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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:

Style	Preview	Description
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.

inherit

Represents the calculated value of the border-top-width of the parent's element.

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Examples

element {
    border-top-width: thin;
    border-top-style: solid;
    border-top-color: #000;
}

.element1{
	border-top: thick solid red;
}
.element2{
	border-top: medium solid orange;
}
.element3{
	border-top: thin solid green;
}

Live Sample

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Compatibility

Desktop browsers

Mobile browsers