code: function addExtendSize(Nightmare, opts) {
      Nightmare.action('size', function (done) {
          console.log('size opts', opts);
  
          this.evaluate_now(() => {
              const w = Math.max(
                  document.documentElement.clientWidth,
                  window.innerWidth || 0
              );
              const h = Math.max(
                  document.documentElement.clientHeight,
                  window.innerHeight || 0
              );
              return {
                  height: h,
                  width: w
              };
          }, done);
      });
  }
docs: 自定义扩展函数： 获得视窗大小