CSS3 RGBa - To: CSS3 - Information and samples

Code used in this page

.alpha70 {
	position: relative;
	z-index: 2;
	width: 100px;
	height: 100px;
	color: #fff;
	margin-top: -30px;
	padding: 10px;
	
	/* Fallback for web browsers that doesn't support RGBa */
	background: rgb(0, 0, 0);
	/* For IE 5.5 - 7*/
	filter:progid:DXImageTransform.Microsoft.gradient(startColorstr=#b2000000, endColorstr=#b2000000);
	/* For IE 8*/
	-ms-filter: "progid:DXImageTransform.Microsoft.gradient(startColorstr=#b2000000, endColorstr=#b2000000)";
	
	/* RGBa with 0.7 opacity */
	background: rgba(0, 0, 0, 0.7);
}