CSS3 box-shadow:

浏览器参照基准:Firefox4 and Later, Chrome5 and Later, Safari5 and Later, Opera10.53 and Later, IE9.0 and Later

基本阴影效果(偏移值都为正):

#box-shadow{
	-moz-box-shadow:5px 5px #999;               /* For Firefox3.6+ */
	-webkit-box-shadow:5px 5px #999;            /* For Chrome5+, Safari5+ */
	box-shadow:5px 5px #999;                    /* For Latest Opera */
}

基本阴影效果(偏移值都为负):

#box-shadow2{
	-moz-box-shadow:-5px -5px #888;               /* For Firefox3.6+ */
	-webkit-box-shadow:-5px -5px #888;            /* For Chrome5+, Safari5+ */
	box-shadow:-5px -5px #888;                    /* For Latest Opera */
}

基本阴影效果(水平偏移为负,垂直偏移为负):

#box-shadow3{
	-moz-box-shadow:-5px 5px #888;               /* For Firefox3.6+ */
	-webkit-box-shadow:-5px 5px #888;            /* For Chrome5+, Safari5+ */
	box-shadow:-5px 5px #888;                    /* For Latest Opera */
}

基本阴影效果(水平偏移为正,垂直偏移为负):

#box-shadow4{
	-moz-box-shadow:5px -5px #888;               /* For Firefox3.6+ */
	-webkit-box-shadow:5px -5px #888;            /* For Chrome5+, Safari5+ */
	box-shadow:5px -5px #888;                    /* For Latest Opera */
}

* 还可以试试把某个偏移值设置为0,这时阴影的效果就只是单边的

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