// JavaScript Document
//The adjustment of class name
function changeClassN(number) {
	if (number == 1){
		document.getElementById('test1').className = 'b';
		document.getElementById('test2').className = 'a';
		document.getElementById('test3').className = 'a';
		document.getElementById('test4').className = 'a';
	} else if (number == 2) {
		document.getElementById('test1').className = 'a';
		document.getElementById('test2').className = 'b';
		document.getElementById('test3').className = 'a';
		document.getElementById('test4').className = 'a';
	} else if (number == 3) {
		document.getElementById('test1').className = 'a';
		document.getElementById('test2').className = 'a';
		document.getElementById('test3').className = 'b';
		document.getElementById('test4').className = 'a';
	} else if (number == 4) {
		document.getElementById('test1').className = 'a';
		document.getElementById('test2').className = 'a';
		document.getElementById('test3').className = 'a';
		document.getElementById('test4').className = 'b';
	}
}