a:hover {
	background:#ffffff; /*要兼容IE6的话必须添加背景色*/
	text-decoration:none;
}
a.tooltip span {
	display:none;
	padding:2px 3px;
	margin-left:8px;
	width:130px;
}
a.tooltip:hover span{
	display:inline;
	position:absolute;
	background:#ffffff;
	border:1px solid #cccccc;
	color:#6c6c6c;
}

Easy <a class="tooltip" href="#">Tooltip<span>This is a Example by imbolo.com.</span></a>.

html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, font, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td {
	margin: 0;
	padding: 0;
	border: 0;
	outline: 0;
	font-size: 100%;
	vertical-align: baseline;
	background: transparent;
}
body {
	line-height: 1;
}
ol, ul {
	list-style: none;
}
blockquote, q {
	quotes: none;
}
blockquote:before, blockquote:after,
q:before, q:after {
	content: none;
}
 
/* 元素获得焦点时的样式! */
:focus {
	outline: 0;
}
 
/* 特殊文本的样式! */
ins {
	text-decoration: none;
}
del {
	text-decoration: line-through;
}
 
/* 细线表格样式 */
table {
	border-collapse: collapse;
	border-spacing: 0;
}

* { outline: 2px dotted red }
* * { outline: 2px dotted green }
* * * { outline: 2px dotted orange }
* * * * { outline: 2px dotted blue }
* * * * * { outline: 1px solid red }
* * * * * * { outline: 1px solid green }
* * * * * * * { outline: 1px solid orange }
* * * * * * * * { outline: 1px solid blue }

.content {
	margin: 0 auto 8px;
	display: table;
	}
 
.content div {
	display: table-cell;
	}
 
＜!--[if IE]＞
.content {
	display: block;
	text-align: center;
	}
.content div {
	display: inline;
	zoom: 1;
}
＜![endif]-->

img { background: url(loading.gif) no-repeat center center; }