按钮加颜色渐变

    background-image: -moz-linear-gradient(top, #ffffff, #f5f5f5);
    background-image: -ms-linear-gradient(top, #ffffff, #f5f5f5);
    background-image: -webkit-gradient(linear, 0 0, 0 100%, from(#ffffff), to(#f5f5f5));
    background-image: -webkit-linear-gradient(top, #ffffff, #f5f5f5);
    background-image: -o-linear-gradient(top, #ffffff, #f5f5f5);
    background-image: linear-gradient(top, #ffffff, #f5f5f5);
    background-repeat: repeat-x;
 filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffffff', endColorstr='#f5f5f5', GradientType=0);