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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

About Vendor Prefixing

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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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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HTML 

              
                <div class="card">
  <h4>Use: <code>min-width: 0</code> + <code>text-overflow: ellipsis</code> + <code>white-space: nowrap</code></h4>
  <div class="target">
    <div class="target__title">
      <strong>Flexbox Layout:</strong> Text here is very very long that it might
      get truncate if this box get resized too small
    </div>
    <div class="target__emoji">
      🎃
    </div>
  </div>
  <div class="target target--grid">
    <div class="target__title">
      <strong>Grid Layout:</strong> Text here is very very long that it might
      get truncate if this box get resized too small
    </div>
    <div class="target__emoji">
      🎃
    </div>
  </div>
</div>
!

CSS 

              
                @import url("https://fonts.googleapis.com/css2?family=Exo:wght@600&display=swap");

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  width: 100vw;
  min-height: 100vh;
  font-family: "Exo", Arial, sans-serif;
  background-color: #557;
  color: #000;
  text-shadow: 1px 1px 0 rgb(255 255 255 / 0.2),
    -1px -1px 0 rgb(255 255 255 / 0.2);
  font-wegith: 600;
  display: grid;
  padding: 1rem;
  gap: 1rem;
  place-content: center;
  justify-items: center;
}

@property --accent {
  syntax: "<color>";
  inherits: false;
  initial-value: #ffeb70;
}

.card {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: min(100%, 640px);
  height: auto;
  padding: 30px;
  margin: 10px;
  border-radius: 10px;
  z-index: 1;
  overflow: hidden;
  position: relative;
  backdrop-filter: blur(20px);
}

.card::before,
.card::after {
  content: "";
  position: absolute;
  opacity: 0.5;
}

.card::before {
  filter: blur(40px) saturate(120%) brightness(1.1);
  font-size: 440pt;
  content: "🥪";
  z-index: -1;
  animation: rotate 12s linear infinite, content 12s linear infinite;
}

.card::after {
  width: 100%;
  height: 100%;
  z-index: -2;
  content: "";
  background: var(--accent);
  animation: accent 12s linear infinite alternate;
}

@keyframes rotate {
  0% {
    transform: rotateZ(0deg);
  }
  100% {
    transform: rotateZ(-360deg);
  }
}

@keyframes accent {
  0% {
    --accent: #ffeb70;
  }
  16.666% {
    --accent: #fd560a;
  }
  33.3333% {
    --accent: #1eddfe;
  }
  50% {
    --accent: #cdf9ff;
  }
  66.6666% {
    --accent: #1296dc;
  }
  83.33333% {
    --accent: #f50d21;
  }
  100% {
    --accent: #09ad21;
  }
}

@keyframes content {
  0% {
    content: "🥪";
  }
  16.666% {
    content: "🌈";
  }
  33.3333% {
    content: "🍧";
  }
  50% {
    content: "🏡";
  }
  66.6666% {
    content: "🌃";
  }
  83.33333% {
    content: "🦜";
  }
  100% {
    content: "🔥";
  }
}

h4 {
  font-size: 1rem;
  white-space: nowrap;
  margin-bottom: 1rem;
}

h4 code {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  padding: 0.125em 0.325em;
  color: #fff;
  background-color: #009688;
  border-radius: 0.12em;
}

.card strong {
  font-weight: 900;
  font-size: 1.25em;
  text-decoration-style: wavy;
  text-decoration-color: #ff006f;
  text-decoration-skip-ink: inherit;
  text-decoration-thickness: from-font;
  text-emphasis-style: inherit;
  text-decoration-line: underline;
  text-underline-offset: 0.125em;
}

.target {
  width: 100%;
  display: flex;
  align-items: center;
  border: 2px dashed #fff;
  padding: 0.5rem;
  animation: resize 12s linear infinite;
  gap: 1rem;
  border-radius: 0.25em;
}

.target__emoji {
  width: max-content;
  font-size: 2rem;
  margin-left: auto;
  flex-shrink: 0;
}

.target__title {
  padding: 5px;
}

@keyframes resize {
  0% {
    max-width: 100%;
  }

  50% {
    max-width: 50%;
  }

  100% {
    max-width: 100%;
  }
}

.target--grid {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: 1fr auto;
  border-color: #1eddfe;
}

.target__title {
  overflow: hidden;
  min-width: 0;
  text-overflow: ellipsis;
  white-space: nowrap;
}
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JS
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