rem布局使用

(function (doc, win) {

var docEl = doc.documentElement,

resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',

recalc = function () {

var clientWidth = docEl.clientWidth;

if (!clientWidth) return;

if(clientWidth>=750){

docEl.style.fontSize = '100px';

}else{

docEl.style.fontSize = 100 * (clientWidth / 750) + 'px';

}

};

console.log(docEl.clientWidth);

if (!doc.addEventListener) return;

win.addEventListener(resizeEvt, recalc, false);

doc.addEventListener('DOMContentLoaded', recalc, false);

})(document, window);