Go to CP ---> Design ---> Design management (css) ---> Paste this :
Code
/* ----////// Banner code css /////------- */
#banners a img {
opacity:0.3; -moz-opacity:0.3; filter:alpha(opacity=40);
}
#banners a:hover img {
Place where ur banners are
[code]<div id="banners">Your banners need to be in here</div>
Place where ur banners are :
Code
<div id="banners">Your banners need to be in here</div>