In this Snippet you can easily apply transparency to any supportive element by adding the following CSS code in your style-sheet. Also, remember to replace selector with the target element of your choice.
filter: alpha(opacity=50); /* internet explorer */
-khtml-opacity: 0.5; /* khtml, old safari */
-moz-opacity: 0.5; /* mozilla, netscape */
opacity: 0.5; /* fx, safari, opera */