My primary CSS file contains the following:
#wrapper {
width: 760px;
margin: 0 auto;
padding: 20px;
/* Fallback for web browsers that do not support RGBA */
background: #ffffff;
/* RGBA with 0.8 opacity */
background: rgba(255, 255, 255, 0.8);
}
For Internet Explorer compatibility, my ie.css file includes the following using conditional comments in the head section:
#wrapper {
background: transparent;
-ms-filter: "progid:DXImageTransform.Microsoft.gradient(startColorstr=#CCFFFFFF,endColorstr=#CCFFFFFF)";
/* IE8 */
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr=#CCFFFFFF,endColorstr=#CCFFFFFF);
/* IE6 & 7 */
zoom: 1;
}
While this setup functions correctly in IE7 and IE9, there is an issue with the background appearing as transparent in IE8.