function toggle(nr){

	var count = 1;
	var menus = 8;

		if (nr != ''){
			for (i=0;i < menus; i++) {
			document.getElementById('menu'+count).style.display = 'none';
			document.getElementById('mainnav'+count).className = 'nav-frst';
			count++;
			}
		if (nr != 0)
			{

			document.getElementById('menu'+nr).style.display = '';
			document.getElementById('mainnav'+nr).className = 'nav-frst-actv';
			}
		}
 		else {
			for (i=0;i < menus; i++) {
			document.getElementById('menu'+count).style.display = 'none';
			document.getElementById('mainnav'+count).className = 'nav-frst';
			count++;
			}
 		}
	}