这是一个如何做的例子：
a.tip { border-bottom: 1px dashed; text-decoration: none}a.tip:hover { cursor: help; position: relative}a.tip span { display: none}a.tip:hover span { border: #c0c0c0 1px dotted; padding: 5px 20px 5px 5px; display: block; z-index: 100; background: url(../images/status-info.png) #f0f0f0 no-repeat 100% 5%; left: 0px; margin: 10px; width: 250px; position: absolute; top: 10px; text-decoration: none}<a href="#" >link<span>This is the CSS tooltip showing up when you mouse over the link</span></a>
