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	<h2>Automatic Aspect Ratios</h2>
	<p>Test loading this page with a slow network connection. You should see a placeholder gray background filling the space where the image eventually loads.</p>
	<p>Your browser is automatically calculating the aspect ratio of the image during load, based on the <code>width</code> & <code>height</code> attributes of the <code>img</code> in your HTML and the <code>width</code> & <code>height</code> properties in your CSS.</p>
	<p>For more details, watch <a href="" target="_blank" rel="noopener"></a>.</p>
	<img src="" width="200" height="300" alt="">



                main {
	display: block;
	max-width: 36rem;
	margin: auto;

img {
	width: 100%;
	height: auto;
	background: gray;

	 * 💡 Someday we'll get the `aspect-ratio` property.
	 * For now, browsers are automatically calculating
	 * aspect ratios for images with `width` & `height`
	 * defined in their HTML.
	/* aspect-ratio: attr(width) / attr(height); */