window.onload = function () {
            getRem(750, 100)
        };
        window.onresize = function () {
            getRem(750, 100)
        };
        function getRem(pwidth, prem) {
            var html = document.getElementsByTagName("html")[0];
            var oWidth = document.body.clientWidth || document.documentElement.clientWidth;
            html.style.fontSize = oWidth / pwidth * prem + "px";
        }
        /(pad|pod|iPad|iPod|iOS)/i.test(navigator.userAgent) && (head = document.getElementsByTagName('head'), viewport = document.createElement('meta'), viewport.name = 'viewport', viewport.content = 'target-densitydpi=device-dpi, width=480px, user-scalable=no', head.length > 0 && head[head.length - 1].appendChild(viewport));