移动端根据dpr适配

    'use strict';
/**
 * @param {Number} [baseFontSize = 100] - 基础fontSize, 默认100px;
 * @param {Number} [fontscale = 1] - 有的业务希望能放大一定比例的字体;
 */
const win = window;
  const _baseFontSize = 150;
  const _fontscale = 1;

  const doc = win.document;
  const ua = navigator.userAgent;
  const matches = ua.match(/Android[\S\s]+AppleWebkit\/(\d{3})/i);
  const UCversion = ua.match(/U3\/((\d+|\.){5,})/i);
  const isUCHd = UCversion && parseInt(UCversion[1].split('.').join(''), 10) >= 80;
  const isIos = navigator.appVersion.match(/(iphone|ipad|ipod)/gi);
  let dpr = win.devicePixelRatio || 1;
  if (!isIos && !(matches && matches[1] > 534) && !isUCHd) {
    // 如果非iOS, 非Android4.3以上, 非UC内核, 就不执行高清, dpr设为1;
    dpr = 1;
  }
  const scale = 1 / dpr;

  let metaEl = doc.querySelector('meta[name="viewport"]');
  if (!metaEl) {
    metaEl = doc.createElement('meta');
    metaEl.setAttribute('name', 'viewport');
    doc.head.appendChild(metaEl);
  }
  metaEl.setAttribute('content', 'width=device-width,user-scalable=no,initial-scale=' +
    scale +',maximum-scale=' + scale + ',minimum-scale=' + scale);
  doc.documentElement.style.fontSize = `${_baseFontSize / 2 * dpr * _fontscale}px`;

在html插入这段代码，然后在样式文件使用base字体为75px的基准转换px到rem即可。必要时还可以通过vh，vw调整。

https://www.jianshu.com/p/e96ccb603a50