完美的解决IE6下fixed定位抖动问题

 

body{_position:absolute; _top:expression(offsetParent.scrollTop);}

#sidenav {
    width: 300px;
    position: fixed; /*--Fix the sidenav to stay in one spot--*/
    float: left; /*--Keeps sidenav into place when Fixed positioning fails--*/
    _position:absolute; _top:expression(offsetParent.scrollTop)
}