function over1() {
		document.ba.src=button_a_roll.src
		document.mn.src=main_a.src
		}
		
	function out1() {
		document.ba.src=button_a.src	
		document.mn.src=main.src
		}

	function over2() {
		document.mn.src=main_b.src
		document.bb.src=button_b_roll.src
		}
		
	function out2() {
		document.mn.src=main.src
		document.bb.src=button_b.src
		}

	function over3() {
		document.mn.src=main_c.src
		document.bc.src=button_c_roll.src
		}
		
	function out3() {
		document.mn.src=main.src
		document.bc.src=button_c.src
		}

	function over4() {
		document.mn.src=main_d.src
		document.bd.src=button_d_roll.src
		}
		
	function out4() {
		document.mn.src=main.src
		document.bd.src=button_d.src
		}