最终效果
这里的关键主要是判断鼠标是从哪个方向进入和离开的
$("li").on("mouseenter mouseleave",function(e) {
var w = this.offsetWidth;
var h = this.offsetHeight;
var x = e.pageX - this.getBoundingClientRect().left - w/2;
var y = e.pageY - this.getBoundingClientRect().top - h/2;
var direction = Math.round((((Math.
