如何在所有浏览器中都没有状态栏和地址栏的全屏模式下显示网页？

function enterFullscreen() {
  var element = document.documentElement;
  if (element.requestFullscreen) {
    element.requestFullscreen();
  } else if (element.mozRequestFullScreen) {
    element.mozRequestFullScreen();
  } else if (element.webkitRequestFullscreen) {
    element.webkitRequestFullscreen();
  } else if (element.msRequestFullscreen) {
    element.msRequestFullscreen();
  }
}

function exitFullscreen() {
  if (document.exitFullscreen) {
    document.exitFullscreen();
  } else if (document.mozCancelFullScreen) {
    document.mozCancelFullScreen();
  } else if (document.webkitExitFullscreen) {
    document.webkitExitFullscreen();
  } else if (document.msExitFullscreen) {
    document.msExitFullscreen();
  }
}

.fullscreen {
  width: 100vw;
  height: 100vh;
  position: fixed;
  top: 0;
  left: 0;
  z-index: 9999;
}