// JScript 文件

function objectFloatTop(div, speed){
    this.speed = 10;
    if (speed){
        this.speed = speed;
    }
    this.div = document.getElementById(div);
    this.yTop = parseInt(this.div.style.top);
    var othis = this;
    setInterval(function(){
        var inow = parseInt(othis.div.style.top);
        var idao = othis.yTop + document.documentElement.scrollTop;
        othis.div.style.top = (inow - (inow - idao)/10) + "px";
    },this.speed);
}