介于纯粹CSS的无图片圆角实在是代码太乱，还是倾向于利用图片结合CSS来自做圆角；
（1）高宽皆自适应：
.roundedcornr_box_510746 {
background: #dddddd url(roundedcornr_510746_grad.gif) repeat top left;width:300px;
}
.roundedcornr_top_510746 div {
background:transparent url(roundedcornr_510746_tl.gif) no-repeat top left;
}
.roundedcornr_top_510746 {
background:transparent url(roundedcornr_510746_tr.gif) no-repeat top right;
}
.roundedcornr_bottom_510746 div {
background:transparent url(roundedcornr_510746_bl.gif) no-repeat bottom left;
}
.roundedcornr_bottom_510746 {
background:transparent url(roundedcornr_510746_br.gif) no-repeat bottom right;
}
.roundedcornr_top_510746 div, .roundedcornr_top_510746,
.roundedcornr_bottom_510746 div, .roundedcornr_bottom_510746 {
width: 100%;
height: 30px;
font-size: 1px;
}
.roundedcornr_content_510746 { margin: 0 30px; }
-->
</style>
<div class="roundedcornr_box_510746">
<div class="roundedcornr_top_510746"><div></div></div>
<div class="roundedcornr_content_510746">
<h1>hello world</h1>
Lorem ipsum dolor sit amet, consectetur
adipisicing elit, sed do eiusmod tempor incididunt
ut labore et dolore magna aliqua. Ut enim ad minim
veniam, quis nostrud exercitation ullamco laboris
nisi ut aliquip ex ea commodo consequat. Duis aute
irure dolor in reprehenderit in voluptate velit esse
cillum dolore eu fugiat nulla pariatur. Excepteur
&n
