<!DOCTYPE html>
<html>
<head>
<script src="http://code.jquery.com/jquery.min.js" type="text/javascript"></script>
<style type="text/css">
.wrapper {
width: 100px;
height: 100px;
}
.block1 {
width: 100px;
height: 100px;
border: 1px solid #f00;
}
.block2 {
display: none;
width: 100px;
height: 100px;
border: 1px solid #0f0;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="block1">blabla</div>
<div class="block2">testtest</div>
<div>
<button>Slide now</button>
<script type="text/javascript">
$(function(){
$("button").click(function(){
$(".block1").slideToggle(1000);
$(".block2").slideToggle(1000);
});
});
</script>
</body>
</html>