Opacity CSS not working in IE8

Question

Setting these (exactly like I have written) has served me when I needed it:

-moz-opacity: 0.70;
opacity:.70;
filter: alpha(opacity=70);

No idea if this still applies to 8, but historically IE doesn't apply several styles to elements that don't "have layout."

see: http://www.satzansatz.de/cssd/onhavinglayout.html

You need to set Opacity first for standards-compliant browsers, then the various versions of IE. See Example:

but this opacity code not work in ie8

.slidedownTrigger
{
    cursor: pointer;
    opacity: .75; /* Standards Compliant Browsers */
    filter: alpha(opacity=75); /* IE 7 and Earlier */
    /* Next 2 lines IE8 */
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=75)";
    filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=75);
}

Note that I eliminated -moz as Firefox is a Standards Compliant browser and that line is no longer necessary. Also, -khtml is depreciated, so I eliminated that style as well.

Furthermore, IE's filters will not validate to w3c standards, so if you want your page to validate, separate your standards stylesheet from your IE stylesheet by using an if IE statement like below:

<!--[if IE]>
<link rel="stylesheet" type="text/css"  href="http://www.mysite.com/css/ie.css" />
<![endif]-->

If you separate the ie quirks, your site will validate just fine.

Apparently alpha transparency only works on block level elements in IE 8. Set display: block.

Using display: inline-block; works on IE8 to resolve this problem.

FWIW, opacity: 0.75 works on all standards-compliant browsers.