!function(win) {
 function resize() {
  var domWidth = domEle.getBoundingClientRect().width;
  if(domWidth / v > 540){
   domWidth = 540 * v;
  }
  win.rem = domWidth / 16;
  domEle.style.fontSize = win.rem + "px";
 }
 var v, initial_scale, timeCode, dom = win.document, domEle = dom.documentElement, viewport = dom.querySelector('meta[name="viewport"]'), flexible = dom.querySelector('meta[name="flexible"]');
 if (viewport) {
  //viewport：<meta name="viewport"content="initial-scale=0.5, minimum-scale=0.5, maximum-scale=0.5,user-scalable=no,minimal-ui"/>
  var o = viewport.getAttribute("content").match(/initial\-scale=(["']"content").match(/initial\-dpr=(["']"data-dpr", v), !viewport) {
  if (viewport = dom.createElement("meta"), viewport.setAttribute("name", "viewport"), viewport.setAttribute("content", "initial-scale=" + initial_scale + ", maximum-scale=" + initial_scale + ", minimum-scale=" + initial_scale + ", user-scalable=no"), domEle.firstElementChild) {
   domEle.firstElementChild.appendChild(viewport)
  } else {
   var m = dom.createElement("div");
   m.appendChild(viewport), dom.write(m.innerHTML)
  }
 }
 win.dpr = v;
 win.addEventListener("resize", function() {
  clearTimeout(timeCode), timeCode = setTimeout(resize, 300)
 }, false);
 win.addEventListener("pageshow", function(b) {
  b.persisted && (clearTimeout(timeCode), timeCode = setTimeout(resize, 300))
 }, false);
 /* 个人觉得没必要完成后就把body的字体设置为12
 "complete" === dom.readyState "px" : dom.addEventListener("DOMContentLoaded", function() {
  //dom.body.style.fontSize = 12 * v + "px"
 }, false);
 */
 resize();
}(window);