如何在加载另一个页面时自动关闭DIV

window.onload = function() {
  var divToClose = document.getElementById('divId');
  divToClose.style.display = 'none';
};

$(document).ready(function() {
  $('#divId').hide();
});

<style>
  .hide-div {
    opacity: 0;
    transition: opacity 0.5s;
  }
  .hide-div.hide {
    opacity: 1;
    animation: hide-div-animation 0.5s forwards;
  }
  @keyframes hide-div-animation {
    0% {
      opacity: 1;
    }
    100% {
      opacity: 0;
    }
  }
</style>

<div id="divId" class="hide-div">
  <!-- DIV内容 -->
</div>

<script>
  window.onload = function() {
    var divToClose = document.getElementById('divId');
    divToClose.classList.add('hide');
  };
</script>