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HTML

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Adding Classes

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About the <head>

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Insecure Resource

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <main>
  <h1 class="t2">Lorem Ipsum</h1>
  <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean tincidunt sagittis dolor et consectetur. Nulla facilisi. Maecenas sed aliquam elit. Aenean a nulla sit amet ante congue pulvinar. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Aliquam eu massa placerat, efficitur velit non, gravida augue. Suspendisse in nibh tristique libero consectetur posuere a non eros. Nullam at elit ac turpis finibus lacinia nec aliquet dolor. Interdum et malesuada fames ac ante ipsum primis in faucibus .</p>
  <div class="image-container">
    <img src="https://picsum.photos/seed/picsum/760/235" />
  </div>
  <p>Duis euismod lorem at dolor consectetur, ut sodales odio scelerisque. Phasellus vel tortor vitae massa laoreet iaculis sed auctor felis. Aliquam erat volutpat. Ut malesuada vulputate ipsum sed vulputate. Donec imperdiet sit amet diam in feugiat. Suspendisse in aliquet purus, eu pulvinar nisl. Sed sed dapibus augue. Cras semper aliquam orci, et congue mi fermentum vitae. Sed viverra lectus vel arcu rutrum, quis commodo ante euismod. Vivamus tincidunt posuere nisi id fermentum hv.</p>
  
  <p>Cras est lorem, tincidunt quis erat id, lobortis ornare turpis. Phasellus eu dui eu nulla rutrum elementum ac eu erat. Pellentesque tempus eros eget purus cursus ornare. Etiam sit amet ex nulla. Nunc posuere massa id nulla vehicula, id elementum eros tristique. Morbi vel quam ac orci elementum pellentesque. Nulla sed augue dignissim, pharetra nisl eget, maximus diam. Mauris pretium rhoncus quam vel aliquet. Ut auctor diam eget nibh tristique eleifend. Quisque neque sem, interdum quis bibendum a, eleifend quis purus. Suspendisse ultrices ipsum eget ligula scelerisque aliquam. In hac habitasse platea dictumst. Pellentesque posuere purus a felis consequat, vestibulum vehicula dolor rutrum. Nulla ac elementum urna, eget molestie enim. Curabitur aliquam condimentum tortor a dictum.</p>

  <p>Duis egestas dui eget metus eleifend commodo. Nulla auctor, magna ut hendrerit cursus, ligula dolor aliquet nibh, ut vulputate elit metus id ex. Suspendisse tempus leo magna, eget mollis magna egestas ut. Sed laoreet nibh vitae bibendum fringilla. Phasellus et mi ante. Maecenas tempor elit ut velit ultricies vulputate. Vestibulum sed iaculis diam.</p>

  <p>Nunc rutrum risus non fringilla volutpat. Curabitur dapibus eros vitae quam feugiat suscipit. Cras accumsan, lectus non egestas efficitur, mauris velit iaculis tellus, non fringilla risus velit ut arcu. Donec lobortis varius velit, at vulputate nisl mollis a. Quisque id turpis non leo luctus lobortis. Praesent a lorem a nulla pretium dignissim vel ac elit. Aenean id volutpat nunc. Nam pulvinar lorem ac blandit pharetra. Sed sed nisl sit amet urna molestie pharetra quis nec lectus. Donec magna tellus, aliquet ac egestas fermentum, tincidunt nec nisl.</p>
</main>
!

CSS 

              
                main {
  margin: 0 auto;
  max-width: 760px;
  padding: 1rem;
}

img {
  width: 100%;
  height: auto;
}

.image-container {  
  aspect-ratio: 760 / 235;
  position: relative;
  animation: background-loading .8s linear infinite alternate;
}

.image-container img {
  position: absolute;
  top: 0;
  left: 0;
}

@keyframes background-loading {
  0% {
    background-color: #f9fafb;
  }
  100% {
    background-color: #d1d5db;
  }
}
!

JS
!
999px

Console