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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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About the <head>

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

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To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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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 

              
                <main rel='main'>
  <section role='presentation'>
    <header></header>
    <article>
      <div class="credit"></div>
    </article>
    <button></button>
  </section>
</main>
!

CSS 

              
                section {
  position: relative;
  width: 140px;
  height: 250px;
  background-color: #efeff3;
  -webkit-animation: window forwards 5s infinite;
  animation: window forwards 5s infinite;
  overflow: hidden;
  box-shadow: 0 2px 4px rgb(0 0 0 / 50%);
}

section > * {
  position: absolute;
}

header {
  top: 0;
  left: 0;
  width: 100%;
  height: 30px;
  border-top: 7px solid #3900b5;
  background-color: #6500f1;
  -webkit-animation: header forwards 5s infinite;
  animation: header forwards 5s infinite;
}

article {
  top: 30px;
  left: 50%;
  width: 140px;
  height: 220px;
  box-shadow: 0 2px 4px rgba(100, 100, 100, 0.1);
  background-color: #fff;
  transform: translateX(-50%);
  -webkit-animation: article forwards 5s infinite;
  animation: article forwards 5s infinite;
}

article::after {
  position: absolute;
  top: 100%;
  margin-top: 15px;
  width: 100%;
  height: 100px;
  background-color: #fff;
  box-shadow: 0 2px 4px rgba(100, 100, 100, 0.1);
  content: "";
}

button {
  position: absolute;
  right: 10px;
  top: 220px;
  margin: 0;
  padding: 0;
  width: 20px;
  height: 20px;
  border: 0;
  border-radius: 100%;
  box-shadow: inset 0 0 1px rgba(0, 0, 0, 0.4), 0 2px 3px rgba(0, 0, 0, 0.2);
  -webkit-appearance: none;
  background-color: #e20269;
  -webkit-animation: button forwards 5s infinite;
  animation: button forwards 5s infinite;
}

@-webkit-keyframes window {
  0%,
  15%,
  90% {
    width: 140px;
    height: 250px;
  }
  30%,
  45% {
    width: 400px;
    height: 300px;
  }
  60%,
  75% {
    width: 560px;
    height: 370px;
  }
}

@keyframes window {
  0%,
  15%,
  90% {
    width: 140px;
    height: 250px;
  }
  30%,
  45% {
    width: 400px;
    height: 300px;
  }
  60%,
  75% {
    width: 560px;
    height: 370px;
  }
}

@-webkit-keyframes header {
  0%,
  15%,
  90% {
    width: 100%;
    height: 30px;
    border-top-width: 7px;
  }
  30%,
  45% {
    height: 90px;
    border-top-width: 12px;
  }
  60%,
  75% {
    height: 105px;
    border-top-width: 14px;
  }
}

@keyframes header {
  0%,
  15%,
  90% {
    width: 100%;
    height: 30px;
    border-top-width: 7px;
  }
  30%,
  45% {
    height: 90px;
    border-top-width: 12px;
  }
  60%,
  75% {
    height: 105px;
    border-top-width: 14px;
  }
}

@-webkit-keyframes article {
  0%,
  15%,
  90% {
    top: 30px;
    width: 140px;
    height: 220px;
  }
  30%,
  45% {
    top: 40px;
    width: 270px;
    height: 220px;
  }
  60%,
  75% {
    top: 50px;
    width: 290px;
    height: 225px;
  }
}

@keyframes article {
  0%,
  15%,
  90% {
    top: 30px;
    width: 140px;
    height: 220px;
  }
  30%,
  45% {
    top: 40px;
    width: 270px;
    height: 220px;
  }
  60%,
  75% {
    top: 50px;
    width: 290px;
    height: 225px;
  }
}

@-webkit-keyframes button {
  0%,
  15%,
  90% {
    right: 10px;
    top: 220px;
    width: 20px;
    height: 20px;
  }
  30%,
  45% {
    right: 20px;
    top: 77px;
    width: 26px;
    height: 26px;
  }
  60%,
  75% {
    right: 25px;
    top: 92px;
    width: 26px;
    height: 26px;
  }
}

@keyframes button {
  0%,
  15%,
  90% {
    right: 10px;
    top: 220px;
    width: 20px;
    height: 20px;
  }
  30%,
  45% {
    right: 20px;
    top: 77px;
    width: 26px;
    height: 26px;
  }
  60%,
  75% {
    right: 25px;
    top: 92px;
    width: 26px;
    height: 26px;
  }
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: radial-gradient(circle, rgb(136 212 255) 0%, rgba(22,36,184,1) 100%);
}

body {
  display: flex;
  justify-content: center;
  align-items: center;
}

.credit {
  position: fixed;
  left: 20px;
  top: 90px;
  background: #e8e8e8;
  width: 60%;
  border-radius: 20px;
  height: 10px;
}

.credit::after {
  content: "";
  position: fixed;
  left: 20px;
  top: 30px;
  background: #e8e8e8;
  width: 55%;
  border-radius: 20px;
  height: 10px;
}

.credit::before {
  content: "";
  position: fixed;
  left: 20px;
  top: 60px;
  background: #e8e8e8;
  width: 40%;
  border-radius: 20px;
  height: 10px;
}

@media (min-height: 500px) {
  .credit {
    display: block;
  }
}

.credit a {
  display: inline-block;
  color: #fff;
  text-decoration: none;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.3);
  transition: border-color ease-out 0.15s;
}

.credit a:focus,
.credit a:hover {
  border-bottom-color: #fff;
}
!

JS
!
999px

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