document.compatMode == "CSS1Compat"

var width = window.innerWidth;var height = window.innerHeight;if(typeof width != "Number"){  // IE    width = document.compatMode == "CSS1Compat" ? document.documentElement.clientWidth : document.body.clientWidth;    height = document.compatMode == "CSS1Compat" ? document.documentElement.clientHeight : document.body.clientHeight;}alert(width + "-------" + height)