var oli1 = document.getElementById('erweima');
		var odiv1 = document.getElementsByClassName('erlist');
		var oli2 = document.getElementById('totel');
		var odiv2 = document.getElementsByClassName('tellist');
		oli1.onmouseover = function(){
			odiv1[0].style.display = 'block';
		};
		oli1.onmouseout = function(){
			odiv1[0].style.display = 'none';
		};
		oli2.onmouseover = function(){
			odiv2[0].style.display = 'block';
		};
		oli2.onmouseout = function(){
			odiv2[0].style.display = 'none';
		};
		function goTop(acceleration, time) {
		    acceleration = acceleration || 0.1;
		    time = time || 20;
		    var x1 = 0;
		    var y1 = 0;
		    var x2 = 0;
		    var y2 = 0;
		    var x3 = 0;
		    var y3 = 0;
		    if (document.documentElement) {
		        x1 = document.documentElement.scrollLeft || 0;
		        y1 = document.documentElement.scrollTop || 0;
		    }
		    if (document.body) {
		        x2 = document.body.scrollLeft || 0;
		        y2 = document.body.scrollTop || 0;
		    }
		    var x3 = window.scrollX || 0;
		    var y3 = window.scrollY || 0;
		    // 滚动条到页面顶部的水平距离 
		    var x = Math.max(x1, Math.max(x2, x3));
		    // 滚动条到页面顶部的垂直距离 
		    var y = Math.max(y1, Math.max(y2, y3));
		    // 滚动距离 = 目前距离 / 速度, 因为距离原来越小, 速度是大于 1 的数, 所以滚动距离会越来越小 
		    var speed = 1 + acceleration;
		    window.scrollTo(Math.floor(x / speed), Math.floor(y / speed));
		    // 如果距离不为零, 继续调用迭代本函数 
		    if (x > 0 || y > 0) {
		        var invokeFunction = "goTop(" + acceleration + ", " + time + ")";
		        window.setTimeout(invokeFunction, time);
		    }
		};