鼠标移出后，红色部分会突然消失，然后又出现，并没有缩回屏幕外

var div1 = document.getElementById('div1'),

share = document.getElementById('share'),

timer = null;

window.onload = function(){

var div1 = document.getElementById('div1');

div1.onmouseover = function(){

startMove();

};

div1.onmouseout = function(){

div1.style.left = -200 + 'px';            //这里

};

}

function startMove(){

var div1 = document.getElementById('div1');

clearInterval(timer);

timer = setInterval(function(){

if(div1.offsetLeft != 0){

div1.style.left = div1.offsetLeft + 10 + 'px';

}

}, 30);

}