图片缩放

#divBimgTop {text-align:center;}
#divBimgTop img {
vertical-align:middle;
max-width:360px;max-height:270px;
width: expression(this.width > 360 && this.width / 360>= this.height / 270 ? 360 : true);
height: expression(this.height > 270 && this.width / 360 < this.height / 270 ? 270 : true);
}