function change() {
	//6.14涓?920px瀹藉害鐨勬椂鍊欓櫎浠ont-size=312.5%鐨剅em澶у皬姣斿€?
	var size = 25;

	if(window.document.body.offsetwidth <= 978 && window.document.body.offsetwidth >= 420 ) {
		size = 12;
	}else if(window.document.body.offsetwidth <= 419){
		size = 10;
	}else {
		size = 25;
	}

	var newfontsize = (window.document.body.offsetwidth / size).tofixed(2);

	var obj = document.getelementsbytagname('html');
	obj[0].style.fontsize = newfontsize + "%";
	
	settimeout(function() {
		$(".m_nav").css("top", $(".nav_header").innerheight() + "px");
	},1000)
}

change();

/* 鐩戝惉绐楀彛澶у皬鍙戠敓鏀瑰彉鏃?*/
window.addeventlistener('resize', function() {
	change();
}, false);