function loadbg()
{
bg=new Array(4);
bg[0]='/themes/koohji/STYLE/default/body_bg/0.gif'
bg[1]='/themes/koohji/STYLE/default/body_bg/1.gif'
bg[2]='/themes/koohji/STYLE/default/body_bg/2.gif'
bg[3]='/themes/koohji/STYLE/default/body_bg/3.gif'
index=Math.floor(Math.random()*bg.length);
document.body.style.background="url("+bg[index]+")";
}