https://www.zhiyitech.cn/public/js/flexible.js

1'use strict';
2(function flexible(window, document) {
3  const docEl = document.documentElement;
4  const dpr = window.devicePixelRatio || 1;
5
6  // adjust body font size
7  function setBodyFontSize() {
8    if (document.body) {
9      document.body.style.fontSize = (12 * dpr) + 'px';
10    } else {
11      document.addEventListener('DOMContentLoaded', setBodyFontSize);
12    }
13  }
14  setBodyFontSize();
15
16  // set 1rem = viewWidth / 10
17  function setRemUnit() {
18    const rem = docEl.clientWidth / 10;
19    docEl.style.fontSize = rem + 'px';
20  }
21
22  setRemUnit();
23
24  // reset rem unit on page resize
25  window.addEventListener('resize', setRemUnit);
26  window.addEventListener('pageshow', function(e) {
27    if (e.persisted) {
28      setRemUnit();
29    }
30  });
31
32  // detect 0.5px supports
33  if (dpr >= 2) {
34    const fakeBody = document.createElement('body');
35    const testElement = document.createElement('div');
36    testElement.style.border = '.5px solid transparent';
37    fakeBody.appendChild(testElement);
38    docEl.appendChild(fakeBody);
39    if (testElement.offsetHeight === 1) {
40      docEl.classList.add('hairlines');
41    }
42    docEl.removeChild(fakeBody);
43  }
44// eslint-disable-next-line no-undef
45}(window, document));