如何显示加载器覆盖，直到图像加载到网页上？

<div id="loader"></div>
<img id="image" src="image.jpg" alt="Image">

#loader {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(255, 255, 255, 0.8);
  display: flex;
  justify-content: center;
  align-items: center;
}

#loader::before {
  content: "";
  width: 50px;
  height: 50px;
  border-radius: 50%;
  border: 5px solid #ccc;
  border-top-color: #333;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

#image {
  display: none;
}

window.addEventListener('load', function() {
  var loader = document.getElementById('loader');
  var image = document.getElementById('image');

  image.addEventListener('load', function() {
    loader.style.display = 'none';
    image.style.display = 'block';
  });
});