<!DOCTYPE html>
<html><head>
<style>
#fixedbutton {
position: fixed;
bottom: 5px;
right: 5px;
}
</style>
</head>
<body>
<script type="text/javascript">
(function() {
var i = 0;
var src = [
'images/1.jpg',
'images/2.jpg',
'images/3.jpg',
'images/4.jpg',
'images/5.jpg',
'images/6.jpg',
'images/7.jpg'
];
var l = src.length;
var t;
for(i = 0; i < l; i++) {
var img = new Image();
img.src = src[i];
img.onload = function() {
delete this;
}
}
i = 0;
t = setInterval(function() {
if(i === l){
clearInterval(t);
} else {
document.body.style.background = 'url(' + src[i] + ') center top no-repeat';
}
i++;
}, 1000);
})();
</script>
<a href="../index.html"><img src="images/upbutton.jpg" id="fixedbutton"></a>
</body>
</html>