今天分享下移动端rem 适配

采用rem布局时，把以下代码粘到js文件内
function font(w) {
var w = w || 640,
docEl = document.documentElement,
resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',
recalc = function () {
var clientWidth = docEl.clientWidth;
if (!clientWidth) return;
docEl.style.fontSize = 100 * (clientWidth / w) + 'px';
};
if (!document.addEventListener) return;
window.addEventListener(resizeEvt, recalc, false);
document.addEventListener('DOMContentLoaded', recalc, false);
}

font();

(function (doc, win) {
var docEl = doc.documentElement,
resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',
recalc = function () {
var clientWidth = docEl.clientWidth;
if (!clientWidth) return;
docEl.style.fontSize = 100 * (clientWidth / 640) + 'px';
};
if (!doc.addEventListener) return;
win.addEventListener(resizeEvt, recalc, false);
doc.addEventListener('DOMContentLoaded', recalc, false);
})(document, window);