@media screen and (max-width:768px){
	.main{ width: 70%; left:50%; margin-left: -35%;}
	.main h3{ font-size: 36px;}
	.nav{padding: 15% 15%;margin-top: 20%;}
	.nav a{ font-size: 24px;}
	.header .header_menu .close_btn{ background-size: 100%;}
}