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.

.selector {
    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 */
}

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