var mainPos=1;
var menuMax=3;

/*tabmenu*/
function TaboverChk(targetNum){
	if(mainPos!=targetNum){
		document["btn"+targetNum].src = "./img/top_tab"+targetNum+"_over.gif";
	}
}

function TaboutChk(targetNum){
	if(mainPos!=targetNum){
		document["btn"+targetNum].src = "./img/top_tab"+targetNum+"_off.gif";
	}
}

function TabclickChk(targetNum){
	if(mainPos!=targetNum){
		for(i=1;i<=menuMax;i++){
			if(i == targetNum){
				$("#tab_purpose"+targetNum).toggle();
				document["btn"+targetNum].src = "./img/top_tab"+targetNum+"_on.gif";
			} else {
				if(i==mainPos){
					$("#tab_purpose"+i).toggle();
					document["btn"+i].src = "./img/top_tab"+i+"_off.gif";
				}
			}
		}
		mainPos=targetNum;
	}
}