/* 当设计图是1920时,规定HTML的FONT-SIZE的值是100. 也就是,当浏览器窗口调整到1920PX时,1REM=100PX,如果要设定一个160PX(1920设计图时)的margin-top,那么REM设置值是1.6rem. */

(function(win) {

var tid;

function refreshRem() {

let designSize = 1920; // 设计图尺寸;

let html = document.documentElement;

let wW = html.clientWidth; // 窗口宽度

let rem = wW * 100 / designSize;

document.documentElement.style.fontSize = rem + 'px';

}

win.addEventListener('resize', function() {

clearTimeout(tid);

tid = setTimeout(refreshRem, 300);

}, false);

win.addEventListener('pageshow', function(e) {

if (e.persisted) {

clearTimeout(tid);

tid = setTimeout(refreshRem, 300);

}

}, false);

refreshRem();

})(window);