You better not use a background image and use the css3 gradient instead. Sort of:
input[type="button"], input[type="submit"], button { background-color: #a3d4ff; background-image: -webkit-gradient(linear, left top, left bottom, from(#a3d4ff), to(#88bcf2)); background-image: -webkit-linear-gradient(top, #a3d4ff, #88bcf2); background-image: -moz-linear-gradient(top, #a3d4ff, #88bcf2); background-image: -o-linear-gradient(top, #a3d4ff, #88bcf2); background-image: linear-gradient(to bottom, #a3d4ff, #88bcf2); border-radius:3px; display: inline-block; line-height: 22px; padding:7px 12px; margin:0; border: 1px solid #88bcf2; color: #FFFFFF; font-size: 15px; font-weight: bold; letter-spacing: -1px; text-shadow: 0 1px 1px #70A7E0; cursor:pointer; }
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