border-bottom property

The border-bottom property specifies a color, type, and width for a bottom border. It is a shorthand property for border-bottom-width, border-bottom-style and border-bottom-color.

Syntax

selector {
	border-bottom: width type color;
}

The order of the properties does not matter.

Let's give the element a black bottom border with 2px width:

<div id="elem"></div>

#elem {
	border-bottom: 2px solid black;
	background: #f9f9f9;
	width: 300px;
	height: 100px;
}