css 背景图片自动缩放实例

.color_checked {
 float: right;
 width: 16px;
 height: 16px;
 background: url(../images/color_check.png) center 0 no-repeat;
 -webkit-background-size: cover;
 -moz-background-size: cover;
 -o-background-size: cover;
 background-size: cover;
}

#blogcon img { max-width: 400px; max-height: 400px; width: expression(this.width>400 && this.width>this.height ? 400 : true); height: expression(this.height > 400 ? 400 : true); }