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HTML

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CSS

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CSS Base

About CSS Base

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <div class="container">
<img class="laptop" 
  srcset="https://leniolabs.com/images/l-layoutit-mob.jpg 470w, https://leniolabs.com/images/l-layoutit.jpg" 
     sizes="(max-width: 470px) 100%, 100%"
  src="https://leniolabs.com/images/l-layoutit.jpg" alt="layoutit">
      <i class="laptop-base"></i>
</div>
<p>Collapse your browser to make the viewport 330px or so, (if you are on chrome reload the page). Start expanding the viewport to the maximum.<br> <a target="_blank" href="https://dribbble.com/shots/5421819-Responsive-images-with-srcset-and-CSS-illustrations?utm_source=Clipboard_Shot&utm_campaign=marianabelda&utm_content=Responsive%20images%20with%20srcset%20and%20CSS%20illustrations&utm_medium=Social_Share">GIF example in dribbble</a></p>
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CSS 

              
                * { box-sizing: border-box; }
body {
  background-color: #00435e;
  color: white;
  font-family: 'Lato', 'Lucida Grande', 'Lucida Sans Unicode', Tahoma, Sans-Serif;
  margin:0;
  text-align:center;
}
img { width:100%; }
a { color: #ff9900; }
p {
  line-height: 1.4;
  margin: 0 auto;
  max-width: 58ch;
}
.container {
  margin: 2em auto;
  max-width: 40em;
  width: 80%;
}
.laptop {
    background: radial-gradient(100% 100% at 50% 50%, rgba(0, 0, 0, 0.4) 49%, transparent 50%) -26px 50%/20px 20px, linear-gradient(0deg, rgba(0, 0, 0, 0.4) 100%, transparent 0) calc(100% + 15px) 50%/6px 80px;
    background-repeat: no-repeat;
    border: 24px solid rgba(0, 0, 0, 0.3);
    border-left-width: 32px;
    border-radius: 15px;
    box-shadow: 0 0 0 4px rgba(0, 0, 0, 0.4);
    transition: background .5s ease-in-out;
}

@media screen and (min-width: 56.25em) {
  .laptop {
      background: radial-gradient(100% 100% at 50% 50%, rgba(0, 0, 0, 0.4) 49%, transparent 50%) 50% -14px/10px 10px;
      background-repeat: no-repeat;
      border-width: 15px 10px 30px;
  }
  .laptop-base {
    background-color: #051d27;
    border-radius: 0 0 15px 15px;
    display: block;
    height: 24px;
    margin-left: -5%;
    margin-top: -20px;
    position: relative;
    width: 110%;
  }
  .laptop-base:after {
      content: "";
      background-color: rgba(255, 255, 255, 0.2);
      border-radius: 0 0 5px 5px;
      display: block;
      height: 5px;
      margin: 0 auto;
      width: 50px;
  }
}

@media screen and (max-width: 470px) {
  .laptop {
      background: radial-gradient(100% 100% at 50% 50%, rgba(0, 0, 0, 0.4) 49%, transparent 50%) 50% calc(100% + 36px)/30px 30px, linear-gradient(90deg, rgba(0, 0, 0, 0.4) 100%, transparent 0) 50% -20px/80px 6px;
      background-repeat: no-repeat;
      border-width: 45px 10px;
      min-height: 480px;
      max-height: 90vh;
      object-fit: cover;
      object-position: top left;
  }
}
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JS
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