<style>
	.detail_img{max-width:300px; }
	.detail_img2{max-width: 100%;}
</style>
<script type="text/javascript">
$("#abc img").each(function(index, element) {
	$(element).addClass('detail_img');
	$(this).toggle(function() {
		$(element).addClass('detail_img2');
		$(element).removeClass('detail_img');
	},function() {
		$(element).addClass('detail_img');
		$(element).removeClass('detail_img2');
	});
});
</script>