// JavaScript Document

window.onload = function(){
//var url = "a.jpg,b.jpg,c.jpg".split(',');
var url=[];
url[0] = 'inquiry_box.jpg';
url[1] = 'inquiry_box2.jpg';
url[2] = 'inquiry_box3.jpg';
url[3] = 'inquiry_box4.jpg';
url[4] = 'inquiry_box5.jpg';
var n = Math.floor(Math.random() * url.length);
var elm = document.getElementById('contact_box');
elm.style.backgroundImage = 'url(http://www.telecomcredit.co.jp/images/' + url[n] + ')';
}