// random background image



if (document.getElementById) { window.onload = swap };
function swap() {
var numimages=5;
rndimg = new Array("images/banner_top_blen.jpg","images/banner_top_downing.jpg","images/banner_top_national.jpg","images/banner_top_stmartins.jpg","images/banner_top1_c.jpg"); 
x=(Math.floor(Math.random()*numimages));
randomimage=(rndimg[x]);
document.getElementById("banner").style.backgroundImage = "url("+ randomimage +")"; 
}