var _demo_parent_id,_demo_current,_demo_last,demo_ids;
_demo_parent_id="demo_border1";
demo_ids=new Array();
demo_ids=["head_demo1","head_demo2"];
_demo_current=0;
_demo_last=0;
function run_demo()
{
    var len=demo_ids.length;
    _demo_last=_demo_current;
    ++_demo_current;
    if(_demo_current>=len) _demo_current=0;
    
    var o;
    o=document.getElementById(demo_ids[_demo_last]);
    o.style.display="none";
    o=document.getElementById(demo_ids[_demo_current]);
    o.style.display="";    
}
function show_demo()
{
    var e=document.getElementById(_demo_parent_id);
    var len=demo_ids.length;
    var x,y;
    x=_getX(e);
    y=_getY(e);
    var o;
    for(var i=0;i<len;i++)
    {
        o=document.getElementById(demo_ids[i]);
        o.style.left=(x+46)+"px";
        o.style.top=(y+16)+"px";
        if(i>0) o.style.display="none";
    }
}
function _getX(elem){
　　var x=0;
　　while(elem){
　　　　x=x+elem.offsetLeft;
　　　　elem=elem.offsetParent;
　　}
　　return x;
}
function _getY(elem){
　　var y=0;
　　while(elem){
　　　　y=y+elem.offsetTop;
　　　　elem=elem.offsetParent;
　　}
　　return y;
}