/* 文档样式 */
body { margin: 1em auto; padding: 1em; width: 760px; font-weight: bold; border: 1px solid green; word-wrap: break-word; }
#one { background: #ffccea }
#two { background: #ccc4f5 }
#three { background: #c4f5c4 }
#two {
position: absolute;
width: 50%;
top: 100px;
left: 50px;
}