固定在左上角，不固定宽度，采用百分比(%)定义宽度来自适应页面

#content {
position: absolute;
top: 0px;
left: 0px;
margin: 20px;
background: #FFF;
border: 5px solid #666;
width: 74%; /* ie5win fudge begins */
padding: 10px 10% 10px 15%;
voice-family: "/"}/"";
voice-family:inherit;
width: 55%;
padding: 10px 9% 10px 11%;
}
html>body #content {
width: 55%;
padding: 10px 9% 10px 11%;
} /* ie5win fudge ends */