u can use java script code

Code:
<script type="text/javascript">

$(document).ready(function(){
	
	$('#read').click(function() {
		$('#req').show()
		$('#read').hide()	
			
		
	})
	$('#unread').click(function() {
		$('#req').hide();
		$('#read').show();
		
	})
	
});


</script>
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