CSS REM adaptation solution

// Netease adaptation Scheme (function(doc, win) { var docEl = doc.documentElement, isIOS = navigator.userAgent.match(/\(i[^;] +; ( U;) ? CPU.+Mac OS X/), dpr = isIOS ? Math.min(win.devicePixelRatio, 3) : 1, dpr = window.top === window.self ? dpr : 1, // Prohibit scaling DPR = 1, scale = 1 / DPR, resizeEvt = when referenced by iframe'orientationchange' in window ? 'orientationchange' : 'resize';
        docEl.dataset.dpr = dpr;
        var metaEl = doc.createElement('meta');
        metaEl.name = 'viewport';
        metaEl.content = 'initial-scale=' + scale + ',maximum-scale=' + scale + ', minimum-scale=' + scale;
        docEl.firstElementChild.appendChild(metaEl);
        var recalc = function() {
        var width = docEl.clientWidth;
        if(width / dpr > 750) { width = 750 * dpr; } // multiply by 100, px: rem = 100:1 docel.style. fontSize = 100 * (width / 750) +'px';
    };
    recalc()
    if(! doc.addEventListener)return;
    win.addEventListener(resizeEvt, recalc, false); })(document, window); // Taobao adaptation scheme (function(win, lib) {
    var doc = win.document;
    var docEl = doc.documentElement;
    var metaEl = doc.querySelector('meta[name="viewport"]');
    var flexibleEl = doc.querySelector('meta[name="flexible"]');
    var dpr = 0;
    var scale = 0;
    var tid;
    var flexible = lib.flexible || (lib.flexible = {});

    if (metaEl) {
        var match = metaEl.getAttribute('content').match(/initial\-scale=([\d\.]+)/);
        if(match) { scale = parseFloat(match[1]); dpr = parseInt(1 / scale); }}else if (flexibleEl) {
        var content = flexibleEl.getAttribute('content');
        if (content) {
            var initialDpr = content.match(/initial\-dpr=([\d\.]+)/);
            var maximumDpr = content.match(/maximum\-dpr=([\d\.]+)/);
            if (initialDpr) {
                dpr = parseFloat(initialDpr[1]);
                scale = parseFloat((1 / dpr).toFixed(2));
            }
            if(maximumDpr) { dpr = parseFloat(maximumDpr[1]); scale = parseFloat((1 / dpr).toFixed(2)); }}}if(! dpr && ! scale) { var isAndroid = win.navigator.appVersion.match(/android/gi); var isIPhone = win.navigator.appVersion.match(/iphone/gi); var devicePixelRatio = win.devicePixelRatio;if(isIPhone) {// On iOS, use 2x for screens 2 and 3, and 1x for the restif(devicePixelRatio >= 3 && (! dpr || dpr >= 3)) { dpr = 3; }else if(devicePixelRatio >= 2 && (! dpr || dpr >= 2)) { dpr = 2; }else{ dpr = 1; }}else{// For other devices, still use 1 times DPR = 1; } scale = 1 / dpr; } docEl.setAttribute('data-dpr', dpr);
    if(! metaEl) { metaEl = doc.createElement('meta');
        metaEl.setAttribute('name'.'viewport');
        metaEl.setAttribute('content'.'initial-scale=' + scale + ', maximum-scale=' + scale + ', minimum-scale=' + scale + ', user-scalable=no');
        if (docEl.firstElementChild) {
            docEl.firstElementChild.appendChild(metaEl);
        } else {
            var wrap = doc.createElement('div'); wrap.appendChild(metaEl); doc.write(wrap.innerHTML); }}function refreshRem() { var width = docEl.getBoundingClientRect().width; // Adapt tabletif (width / dpr > 540) {
            width = 540 * dpr;
        }
        var rem = width / 10;
        docEl.style.fontSize = rem + 'px';
        flexible.rem = win.rem = rem;
    }

    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);

    if (doc.readyState === 'complete') {
        doc.body.style.fontSize = 12 * dpr + 'px';
    } else {
        doc.addEventListener('DOMContentLoaded'.function(e) {
            doc.body.style.fontSize = 12 * dpr + 'px';
        }, false);
    }


    refreshRem();

    flexible.dpr = win.dpr = dpr;
    flexible.refreshRem = refreshRem;
    flexible.rem2px = function(d) {
        var val = parseFloat(d) * this.rem;
        if (typeof d === 'string' && d.match(/rem$/)) {
            val += 'px';
        }
        return val;
    }
    flexible.px2rem = function(d) {
        var val = parseFloat(d) / this.rem;
        if (typeof d === 'string' && d.match(/px$/)) {
            val += 'rem';
        }
        return val;
    }

})(window, window['lib'] || (window['lib'] = {}));Copy the code