// JScript 文件
var step = 30;
function prorgt(){
    while(document.getElementById("proccc").scrollLeft<645){
        document.getElementById("proccc").scrollLeft = document.getElementById("proccc").scrollLeft+step;
    }
    
    document.getElementById("proccc").scrollLeft = 645;
    document.getElementById("srbtn").style.backgroundImage = "url(http://img7.cn.msn.com/7/righta.gif)";
    document.getElementById("slbtn").style.backgroundImage = "url(http://img5.cn.msn.com/5/leftb.gif)";
}

function prolft(){
    while(document.getElementById("proccc").scrollLeft>0){
        document.getElementById("proccc").scrollLeft = document.getElementById("proccc").scrollLeft-step;
    
    }
    
    document.getElementById("proccc").scrollLeft = 0;
    document.getElementById("srbtn").style.backgroundImage = "url(http://img7.cn.msn.com/7/rightb.gif)";
    document.getElementById("slbtn").style.backgroundImage = "url(http://img5.cn.msn.com/5/lefta.gif)";
}