<div class="img-area">
  <img class="img" src="https://www.pc-weblog.com/sample/img/images/pic-1280.jpg"  width="1280" height="720">
</div>
img {
  max-width: 100%;
}

.img-area {
  max-width: 500px;
}

.img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

External CSS

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External JavaScript

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