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HTML

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About the <head>

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Insecure Resource

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CSS

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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.

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JavaScript

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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="message success">
  <svg viewBox="0 0 56.693 56.693">
    <use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-complete"></use>
  </svg>
  <h1>
    Zoom Allowed
  </h1>
  <p>
    <img src="http://www.fillmurray.com/640/480" alt="">
    Look, it’s a photo of Bill Murray that is being shown way smaller than actual size. Imagine if there was some important detail we needed to see in order to solve a murder case and you wanted to impress your boss by saying <em>enhance</em> loudly but were really just spread-zooming on the trackpad. Then you’d look awesome.
  </p>
  <p>
    Example from my blog post <em><a href="http://adrianroselli.com/2015/10/dont-disable-zoom.html">Don’t Disable Zoom</a></em>. I borrowed this alert message box thinger from <a href="https://codepen.io/aardrian/pen/rVZKoR">another pen I made to test SVGs</a>.
  </p>
</div>


<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" id="SVGsprites">
  <defs>
    <g id="icon-complete" aria-labeledby="title-02" aria-describedby="desc-02" role="image">
      <title id="title-02">Checkmark icon</title>
      <desc id="desc-02">Symbol showing a checkmark.</desc>
      <path d="M51.858 10.72c-.653-.15-1.834-.295-3.616-.447-1.827-.153-2.956-.168-3.555-.053-.606.117-1.7.672-3.348 1.7-1.6 1-4.05 2.975-7.283 5.865-3.232 2.896-6.387 6.062-9.377 9.41-2.786 3.117-5.517 6.44-8.13 9.89-.978-2.918-1.983-4.97-3.07-6.254-1.22-1.448-2.33-2.27-3.386-2.51-.845-.195-1.934-.01-3.335.567-1.44.59-2.275 1.353-2.483 2.268-.157.69.17 1.687 1.03 3.14 1.518 2.563 2.788 5.236 3.777 7.95.634 1.69 1.067 2.72 1.324 3.145.216.356.758.832 3.05 1.354 1.17.268 2.134.402 2.865.402.783 0 1.34-.152 1.69-.457.575-.48 1.722-1.947 3.506-4.486 4.283-6.155 9.23-11.925 14.704-17.153 5.473-5.226 10.323-9.077 14.41-11.44 1.25-.69 1.49-.88 1.573-.946.267-.217.438-.48.506-.775.102-.448-.07-.99-.855-1.17z"/>
    </g>
</svg>
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CSS 

              
                body {
  background-color: #6D695C;
  background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAMAAAAoLQ9TAAAACVBMVEUAAAAAAAAAAACDY+nAAAAAA3RSTlMmDQBzGIDBAAAAG0lEQVR42uXIIQEAAADCMHj/0NdkQMws0HEeAqvwAUGJthrXAAAAAElFTkSuQmCC);
  color: #333;
  font-family: Arial, Helvetica, sans-serif;
  padding: 0;
  margin: 0;
}

h1 {
  font-size: 150%;
  margin: .75em 0 .5em 0;
}

img {
  float: right;
  width: 50px;
  height: auto;
  max-width: 25%;
  margin: 0 0 1em 1em
}

#SVGsprites {
  display: none;
}

.message {
  box-sizing: border-box;
  border: 2px solid #ccc;
  background-color: #fff;
  padding: .5em 1em .5em 70px;
  margin: 1em 2em;
  border-radius: .5em;
  min-height: 70px;
  position: relative;
}

.message svg {
  position: absolute;
  top: .5em;
  left: 10px;
  width: 50px;
  height: auto;
}

.message.success {
  border-color: #6c6;
}

.message.success svg {
  fill: #6c6;
}

.message.success h1 {
  color: #35a035;
}

message.alert {
  border-color: #f99;
  box-shadow: 0 0 20px rgba(255,0,0,.5);
}

.message.alert svg {
  fill: #f99;
}

.message.alert h1 {
  color: #ff5d5d;
}

.message.alert.throbbing {
    animation: alertBorderThrob 1s infinite alternate;
}

.message.alert.throbbing svg {
  animation: alertSVGThrob 1s infinite alternate;
}

@keyframes alertBorderThrob {
  from {
    border-color: #f99;
    box-shadow: 0 0 20px rgba(255,0,0,.5);
    animation-timing-function: linear;
  } to {
    border-color: #f00;box-shadow: 0 0 20px rgba(255,0,0,1);
  }
}

@keyframes alertSVGThrob {
  from {
    fill: #f99;
    animation-timing-function: linear;
  } to {
    fill: #f00;
  }
}
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JS
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