获取屏幕宽高的简单方式之一

mounted() {
  let w = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth;
  let h = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight;
  this.$refs.subject.style.height = h + 'px';
  this.$refs.rightAnswer.style.height = h + 'px';
  this.$refs.sc.style.height = h + 'px';
}

vue里用let  相当于var