I made a violin for you. You should use gradients with rgba. This is not supported in all browsers, so you may want to manipulate them. However, this is the only way to do this in CSS.
Here is the code:
HTML:
<html> <head> </head> <body> <img src="http://upload.wikimedia.org/wikipedia/meta/6/6d/Wikipedia_wordmark_1x.png" /> <div class="whatever"></div> </body> </html>
CSS
body { margin:0px; } img { height:30px; position:relative; } .whatever { background-image: -webkit-gradient( linear, left top, left bottom, color-stop(0, #ff00ff), color-stop(1, rgba(0,0,0,0)) ); background-image: -o-linear-gradient(bottom, #ff00ff 0%, rgba(0,0,0,0) 100%); background-image: -moz-linear-gradient(bottom, #ff00ff 0%, rgba(0,0,0,0) 100%); background-image: -webkit-linear-gradient(bottom, #ff00ff 0%, rgba(0,0,0,0) 100%); background-image: -ms-linear-gradient(bottom, #ff00ff 0%, rgba(0,0,0,0) 100%); background-image: linear-gradient(to bottom, #ff00ff 0%, rgba(0,0,0,0) 100%); height:30px; position:relative; width:100px; top:-34px; }