CSS实现图片按比例缩放

.image {
max-width:600px;
height:auto;
cursor:pointer;
//border:1px dashed #4E6973;
//padding: 3px;
zoom:expression( function(elm) {
if (elm.width>360) {
var oldVW = elm.width;
elm.width=360;
elm.height = elm.height*(360 /oldVW);
}
elm.style.zoom = '1';
}(this)
);
}

/*<img src="url" class="image" />*/