CSS ROUNDED CORNERS FOR BORDERS WITHOUT USING IMAGES
The CSS can get rounding borders for DIV's without using any image.
I present the following codes for various alterations of borders form ( corners ) only using CSS .
STEP 1
CSS codes for each example. Copy this styles CSS in head section of your page.
<style type="text/css">
body {font-family:Arial, Helvetica, sans-serif, Tahoma; font-size:11px;}
#info {display:block; position:relative; background:#cccccc;}
#info h2 {margin-bottom:1em;}
#info h3 {clear:both; margin-top:4em;}
/* Inset 3D Raised */
.raised {background: transparent; width:40%; margin:0 auto;}
.raised h1, .raised p {margin:0 10px;}
.raised h1 {font-size:2em; color:#fff; letter-spacing:1px;}
.raised p {padding-bottom:0.5em;}
.raised .top, .raised .bottom {display:block; background:transparent; font-size:1px;}
.raised .b1, .raised .b2, .raised .b3, .raised .b4, .raised .b1b, .raised .b2b, .raised .b3b, .raised .b4b {display:block; overflow:hidden;}
.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;}
/* Inset 3D Curved */
.inset {background: transparent; width:40%; margin:0 auto;}
.inset h1, .inset p {margin:0 10px;}
.inset h1 {font-size:2em; color:#fff; letter-spacing:1px;}
.inset p {padding-bottom:0.5em;}
.inset .top, .inset .bottom {display:block; background:transparent; font-size:1px;}
.inset .b1, .inset .b2, .inset .b3, .inset .b4, .inset .b1b, .inset .b2b, .inset .b3b, .inset .b4b {display:block; overflow:hidden;}
.inset .b1, .inset .b2, .inset .b3, .inset .b1b, .inset .b2b, .inset .b3b {height:1px;}
.inset .b2 {background:#ccc; border-left:1px solid #999; border-right:1px solid #aaa;}
.inset .b3 {background:#ccc; border-left:1px solid #999; border-right:1px solid #ddd;}
.inset .b4 {background:#ccc; border-left:1px solid #999; border-right:1px solid #eee;}
.inset .b4b {background:#ccc; border-left:1px solid #aaa; border-right:1px solid #fff;}
.inset .b3b {background:#ccc; border-left:1px solid #ddd; border-right:1px solid #fff;}
.inset .b2b {background:#ccc; border-left:1px solid #eee; border-right:1px solid #fff;}
.inset .b1 {margin:0 5px; background:#999;}
.inset .b2, .inset .b2b {margin:0 3px; border-width:0 2px;}
.inset .b3, .inset .b3b {margin:0 2px;}
.inset .b4, .inset .b4b {height:2px; margin:0 1px;}
.inset .b1b {margin:0 5px; background:#fff;}
.inset .boxcontent {display:block; background:#ccc; border-left:1px solid #999; border-right:1px solid #fff;}
/* Chamfer Borders*/
.chamfer {background: transparent; width:40%; margin:0 auto;}
.chamfer h1, .chamfer p {margin:0 10px;}
.chamfer h1 {font-size:2em; color:#000; letter-spacing:1px;}
.chamfer p {padding-bottom:0.5em;}
.chamfer .top, .chamfer .bottom {display:block; background:transparent; font-size:1px;}
.chamfer .b1, .chamfer .b2, .chamfer .b3, .chamfer .b4, .chamfer .b5 {display:block; overflow:hidden; height:1px; background:#eca; border-left:1px solid #000; border-right:1px solid #000;}
.chamfer .b1 {margin:0 5px; background:#000;}
.chamfer .b2 {margin:0 4px;}
.chamfer .b3 {margin:0 3px;}
.chamfer .b4 {margin:0 2px;}
.chamfer .b5 {margin:0 1px;}
.chamfer .boxcontent {display:block; background:#eca; border-left:1px solid #000; border-right:1px solid #000;}
/* Square cutout Borders*/
.square {background: transparent; width:40%; margin:0 auto;}
.square h1, .square p {margin:0 10px;}
.square h1 {font-size:2em; color:#00c; letter-spacing:1px;}
.square p {padding-bottom:0.5em;}
.square .top, .square .bottom {display:block; background:transparent; font-size:1px;}
.square .b1t {margin:0 6px; display:block; overflow:hidden; height:5px; background:#9ce; border-left:1px solid #00c; border-right:1px solid #00c; border-top:1px solid #00c;}
.square .b2 {display:block; height:1px; margin:0; background:#9ce; border-left:7px solid #00c; border-right:7px solid #00c; overflow:hidden;}
.square .b1b {margin:0 6px; display:block; overflow:hidden; height:5px; background:#9ce; border-left:1px solid #00c; border-right:1px solid #00c; border-bottom:1px solid #00c;}
.square .boxcontent {display:block; background:#9ce; border-left:1px solid #00c; border-right:1px solid #00c;}
/* Curved cutout Borders*/
.curved {background: transparent; width:40%; margin:0 auto;}
.curved h1, .curved p {margin:0 10px;}
.curved h1 {font-size:2em; color:#fff; letter-spacing:1px;}
.curved p {padding-bottom:0.5em;}
.curved .top, .curved .bottom {display:block; background:transparent; font-size:1px;}
.curved .b1, .curved .b2, .curved .b3, .curved .b4 {display:block; overflow:hidden; height: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;}
/* flared serif */
.serif {background: transparent; width:40%; margin:0 auto;}
.serif h1, .serif p {margin:0 10px;}
.serif h1 {font-size:2em; color:#fff; letter-spacing:1px;}
.serif p {padding-bottom:0.5em;}
.serif .top, .serif .bottom {display:block; background:transparent; font-size:1px;}
.serif .b1, .serif .b2, .serif .b3, .serif .b4 {display:block; overflow:hidden;}
.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;}
/* Pillar type */
.pillar {background: transparent; width:40%; margin:0 auto;}
.pillar h1, .pillar p {margin:0 10px;}
.pillar h1 {font-size:2em; color:#fff; letter-spacing:1px;}
.pillar p {padding-bottom:0.5em;}
.pillar .top, .pillar .bottom {display:block; background:transparent; font-size:1px;}
.pillar .b1, .pillar .b2, .pillar .b3, .pillar .b4 {display:block; overflow:hidden;}
.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;}
/* Barrel cutout Borders*/
.barrel {background: transparent; width:40%; margin:0 auto;}
.barrel h1, .barrel p {margin:0 10px;}
.barrel h1 {font-size:2em; color:#fff; letter-spacing:1px;}
.barrel p {padding-bottom:0.5em;}
.barrel .top, .barrel .bottom {display:block; background:transparent; font-size:1px;}
.barrel .b1, .barrel .b2, .barrel .b3, .barrel .b4, .barrel .b5 {display:block; overflow:hidden; height:1px; background:#e0cea3;}
.barrel .b1 {border-left:10px solid #dfd5c0; border-right:10px solid #dfd5c0;}
.barrel .b2 {border-left:5px solid #dfd5c0; border-right:5px solid #dfd5c0;}
.barrel .b3 {border-left:3px solid #dfd5c0; border-right:3px solid #dfd5c0;}
.barrel .b4 {border-left:2px solid #dfd5c0; border-right:2px solid #dfd5c0;}
.barrel .b5 {border-left:1px solid #dfd5c0; border-right:1px solid #dfd5c0;}
.barrel .b1 {margin:0 33%;}
.barrel .b2 {margin:0 20%;}
.barrel .b3 {margin:0 12%;}
.barrel .b4 {margin:0 5%;}
.barrel .b5 {margin:0 1px;}
.barrel .boxcontent {display:block; background:#e0cea3; border-left:1px solid #fff; border-right:1px solid #999;}
</style>
STEP2:
Copy this CSS into your <body> section </body>
<div id="info">
<h2>Corners</h2>
<div class="raised">
<b class="top"><b class="b1"></b><b class="b2"></b><b class="b3"></b><b class="b4"></b></b>
<div class="boxcontent">
<h1>3D Raised</h1>
<p>Rounded corners with raised borders</p>
</div>
<b class="bottom"><b class="b4b"></b><b class="b3b"></b><b class="b2b"></b><b class="b1b"></b></b>
</div>
<p></p>
<div class="inset">
<b class="top"><b class="b1"></b><b class="b2"></b><b class="b3"></b><b class="b4"></b></b>
<div class="boxcontent">
<h1>3D Inset</h1>
<p>Rounded corners with inset borders</p>
</div>
<b class="bottom"><b class="b4b"></b><b class="b3b"></b><b class="b2b"></b><b class="b1b"></b></b>
</div>
<p></p>
<div class="pillar">
<b class="top"><b class="b1"></b><b class="b2"></b><b class="b3"></b><b class="b2"></b><b class="b4"></b></b>
<div class="boxcontent">
<h1>Pillar shape</h1>
<p>Corners to give a rounded pillar effect.</p>
</div>
<b class="bottom"><b class="b4"></b><b class="b2"></b><b class="b3"></b><b class="b2"></b><b class="b1"></b></b>
</div>
<p></p>
<div class="square">
<b class="top"><b class="b1t"></b><b class="b2"></b></b>
<div class="boxcontent">
<h1>Square cutout Border</h1>
<p>A box with cutout corners</p>
</div>
<b class="bottom"><b class="b2"></b><b class="b1b"></b></b>
</div>
<p></p>
<div class="chamfer">
<b class="top"><b class="b1"></b><b class="b2"></b><b class="b3"></b><b class="b4"></b><b class="b5"></b></b>
<div class="boxcontent">
<h1>Chamfer Border</h1>
<p>A 45 degree border</p>
</div>
<b class="bottom"><b class="b5"></b><b class="b4"></b><b class="b3"></b><b class="b2"></b><b class="b1"></b></b>
</div>
<p></p>
<div class="curved">
<b class="b1"></b><b class="b2"></b><b class="b3"></b><b class="b4"></b>
<div class="boxcontent">
<h1>Curved cutout Border</h1>
<p>A box with cutout corners</p>
</div>
<b class="bottom"><b class="b4"></b><b class="b3"></b><b class="b2"></b><b class="b1"></b></b>
</div>
<p></p>
<div class="serif">
<b class="top"><b class="b1"></b><b class="b2"></b><b class="b3"></b><b class="b4"></b></b>
<div class="boxcontent">
<h1>Flared shape</h1>
<p>Corners to give a serif effect.</p>
</div>
<b class="bottom"><b class="b4"></b><b class="b3"></b><b class="b2"></b><b class="b1"></b></b>
</div>
<p></p>
<p></p>
<div class="barrel">
<b class="top"><b class="b1"></b><b class="b2"></b><b class="b3"></b><b class="b4"></b><b class="b5"></b></b>
<div class="boxcontent">
<h1>Barrel shape</h1>
<p>A box with top and bottom bulges.</p>
</div>
<b class="bottom"><b class="b5"></b><b class="b4"></b><b class="b3"></b><b class="b2"></b><b class="b1"></b></b>
</div>
</div>
You can find this example and more rounded corners on this DEMO page
