rem.js程式碼:

(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';
}
var html = document.getElementsByTagName('html')[0];
var settedFs = settingFs = parseInt(100 * (clientWidth / 750));
var whileCount = 0;
while (true) {
var realFs = parseInt(window.getComputedStyle(html).fontSize);
var delta = realFs - settedFs;
//不相等
if (Math.abs(delta) >= 1) {
if (delta > 0)
settingFs--;
else
settingFs++;
html.setAttribute('style', 'font-size:' + settingFs + 'px!important');
} else
break;
if (whileCount++ > 100)
break
}
};
if (!doc.addEventListener) return;
win.addEventListener(resizeEvt, recalc, false);
doc.addEventListener('DOMContentLoaded', recalc, false);
})(document, window);

使用時，引入rem.js

1rem=100px

用rem代替px寫樣式