CSS background opacity with rgba not working in IE 8

I am using this CSS for background opacity of a <div>:

background: rgba(255, 255, 255, 0.3);

It’s working fine in Firefox, but not in IE 8. How do I make it work?

Solution 1:

To simulate RGBA and HSLA background in IE, you can use a gradient filter, with the same start and end color (alpha channel is the first pair in the value of HEX)

background: rgba(255, 255, 255, 0.3); /* browsers */
filter: progid:DXImageTransform.Microsoft.gradient(GradientType=0,startColorstr='#4cffffff', endColorstr='#4cffffff'); /* IE */

Solution 2:

Create a png which is larger than 1x1 pixel (thanks thirtydot), and which matches the transparency of your background.

EDIT : to fall back for IE6+ support, you can specify bkgd chunk for the png, this is a color which will replace the true alpha transparency if it is not supported. You can fix it with gimp eg.

Solution 3:

I believe this is the best because on this page has a tool to help you generate alpha-transparent background:

"Cross browser alpha transparent background CSS (rgba)" ^{_{(*now linked to archive.org)}}

#div {
    background:rgb(255,0,0);
    background: transparent\9;
    background:rgba(255,0,0,0.3);
    filter:progid:DXImageTransform.Microsoft.gradient(startColorstr=#4cFF0000,endColorstr=#4cFF0000);
    zoom: 1;
}