代码如下:

<style type=\"text/css\">
#round {
height: 200px;
width:100px;
margin:0px auto;
background-image: -moz-linear-gradient(top, #F00, #000);
background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0, #F00), color-stop(1,#000));
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr=\'#F00\', endColorstr=\'#000\', GradientType=\'0\');
}
</style>
<div id=\"round\"></div>