特效介绍
5种没有图片的css圆角效果，简洁型、立体的、反向的、菱形的和反向菱形的等。兼容IE6。关于其原理，可以访问：纯CSS打造支持IE6的无图片圆角教程
使用方法
1、在head区域引入css样式，并非全都引用，需要那种效果就引用哪段css样式：<style type="text/css">
*{margin:0;padding:0;list-style-type:none;}
a,img{border:0;}
body{font:12px/180% Arial, Helvetica, sans-serif, "新宋体";}
.demo{width:760px;margin:0 auto;}
/*简洁型css圆角矩形*/
.b1,.b2,.b3,.b4,.b1b,.b2b,.b3b,.b4b,.b{display:block;overflow:hidden;}
.b1,.b2,.b3,.b1b,.b2b,.b3b{height:1px;}
.b2,.b3,.b4,.b2b,.b3b,.b4b,.b{border-left:1px solid #999;border-right:1px solid #999;}
.b1,.b1b{margin:0 5px;background:#999;}
.b2,.b2b{margin:0 3px;border-width:2px;}
.b3,.b3b{margin:0 2px;}
.b4,.b4b{height:2px;margin:0 1px;}
.d1{background:#F7F8F9;}
.k{height:300px;}
/*3D圆角矩形*/
.raised{background:transparent;width:40%;}
.raised h1,.raised p{margin:0 10px;}
.raised h1{font-size:2em;color:#fff;}
.raised p{padding-bottom:0.5em;}
.raised .b1,.raised .b2,.raised .b3,.raised .b4,.raised .b1b,.raised .b2b,.raised .b3b,.raised .b4b{display:block;overflow:hidden;font-size:1px;}
.raised .b1,.raised .b2,.raised .b3,.raised .b1b,.raised .b2b,.raised .b3b{height:1px;}
.raised .b2{background:#ccc;border-left:1px solid #fff;border-right:1px solid #eee;}
.raised .b3{background:#ccc;border-left:1px solid #fff;border-right:1px solid #ddd;}
.raised .b4{background:#ccc;border-left:1px solid #fff;border-right:1px solid #aaa;}
.raised .b4b{background:#ccc;border-left:1px solid #eee;border-right:1px solid #999;}
.raised .b3b{background:#ccc;border-left:1px solid #ddd;border-right:1px solid #999;}
.raised .b2b{background:#ccc;border-left:1px solid #aaa;border-right:1px solid #999;}
.raised .b1{margin:0 5px;background:#fff;}
.raised .b2, .raised .b2b{margin:0 3px;border-width:0 2px;}
.raised .b3, .raised .b3b{margin:0 2px;}
.raised .b4, .raised .b4b{height:2px;margin:0 1px;}
.raised .b1b{margin:0 5px;background:#999;}
.raised .boxcontent{display:block;background:#ccc;border-left:1px solid #fff;border-right:1px solid #999;}
/*反向css圆角矩形*/
.serif{background:transparent;width:40%;}
.serif h1, .serif p{margin:0 10px;}
.serif h1{font-size:2em;color:#fff;}
.serif p{padding-bottom:0.5em;}
.serif .b1, .serif .b2, .serif .b3, .serif .b4{display:block;overflow:hidden;font-size:1px;}
.serif .b1, .serif .b2, .serif .b3{height:1px;}
.serif .b2, .serif .b3{background:#fc0;border-left:1px solid #fff;border-right:1px solid #fff;}
.serif .b4{background:#fc0;border-left:1px solid #fff;border-right:1px solid #fff;}
.serif .b1{margin:0;background:#fff;}
.serif .b2{margin:0 1px;border-width:0 2px;}
.serif .b3{margin:0 3px;}
.serif .b4{height:2px;margin:0 4px;}
.serif .boxcontent{display:block; background:#fc0;border-left:1px solid #fff;border-right:1px solid #fff;margin:0 5px;}
/*略带菱形的css圆角矩形*/
.curved{background:transparent;width:40%;}
.curved h1, .curved p{margin:0 10px;}
.curved h1{font-size:2em;color:#fff;}
.curved p{padding-bottom:0.5em;}
.curved .b1, .curved .b2, .curved .b3, .curved .b4{display:block;overflow:hidden;height:1px;font-size:1px;}
.curved .b2, .curved .b3, .curved .b4{background:#e0cea3;border-left:1px solid #fff;border-right:1px solid #fff;}
.curved .b1{margin:0 4px;background:#fff;}
.curved .b2{margin:0 4px;height:2px;}
.curved .b3{margin:0 3px;}
.curved .b4{margin:0;height:1px;border-width:0 3px 0 3px;}
.curved .boxcontent{display:block;background:#e0cea3;border:0 solid #fff;border-width:0 1px;}
/*特殊css圆角矩形*/
.pillar{background:transparent;width:40%;}
.pillar h1, .pillar p{margin:0 10px;}
.pillar h1{font-size:2em;color:#fff;}
.pillar p{padding-bottom:0.5em;}
.pillar .b1, .pillar .b2, .pillar .b3, .pillar .b4{display:block;overflow:hidden;font-size:1px;}
.pillar .b1, .pillar .b2, .pillar .b4{height:1px;}
.pillar .b2, .pillar .b3{background:#d66;border-left:1px solid #fff;border-right:1px solid #fff;}
.pillar .b4{background:#d66;border-left:4px solid #fff;border-right:4px solid #fff;}
.pillar .b1{margin:0 2px;background:#fff;}
.pillar .b2{margin:0 1px;border-width:0 1px;}
.pillar .b3{height:2px;margin:0;}
.pillar .b4{margin:0 2px;}
.pillar .boxcontent{display:block;background:#d66;border-left:1px solid #fff;border-right:1px solid #fff;margin:0 5px;}
</style>
2、需要那种效果，在html引入相关代码，例如，需要菱形的，就引入下面的代码：<div class="curved"> <b class="b1"></b><b class="b2"></b><b class="b3"></b><b class="b4"></b> <div class="boxcontent"> <h1>略带菱形的css圆角矩形</h1> </div> <b class="b4"></b><b class="b3"></b><b class="b2"></b><b class="b1"></b> </div>