前端使用rem适配手机屏幕

(function(doc, win) {
	var docEl = doc.documentElement,
		resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',
		recalc = function() {
			var clientWidth = docEl.clientWidth;
			if(!clientWidth) return;
                        //根据设计图的尺寸进行调整
			docEl.style.fontSize = 37.5 * (clientWidth / 375) + 'px';
		};
	if(!doc.addEventListener) return;
	win.addEventListener(resizeEvt, recalc, false);
	doc.addEventListener('DOMContentLoaded', recalc, false);
})(document, window);