需求：需要在视窗内随意点击对应位置，图层从上到下匀速运动到指定位置
html
<img id="moveDot" class="moveDot" src="data:images/moveDot.png">
js
//地图插点动态效果
//横坐标
var x=120;
//纵坐标
var y=200;
var style = document.styleSheets[0];
style.insertRule('.moveDot {width:30px;height:auto;position:absolute;left:'+x +'px;top:'+y +'px;z-index:999999;animation:mymove 500ms;-webkit-animation:mymove 500ms;animation-timing-function:linear;}', 0);
style.insertRule('@keyframes mymove{from{ top:0; }to{top:'+y +'px;}}',0);
style.insertRule('@-webkit-keyframes mymove{from{ top:0; }to{top:'+y +'px;}}',0);