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    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width">
    <title>Accessible image example</title>
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      img {
        display: block;
        margin: 3em;
      }
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    <h1>Images</h1>

    <img src="dinosaur.png">

    <img src="dinosaur.png"
         alt="A red Tyrannosaurus Rex: A two legged dinosaur standing upright like a human, with small arms, and a large head with lots of sharp teeth.