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HTML

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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.

Vendor Prefixing

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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 m-t-md">
  <!-- First row -->
  <div class="row">
    <div class="col-xs-12 col-md-4">
      <!-- Card -->
      <article class="card animated fadeInLeft">
        <img class="card-img-top img-responsive" src="https://snap-photos.s3.amazonaws.com/img-thumbs/960w/1U2EGZ07GU.jpg" alt="Deer in nature" />
        <div class="card-block">
          <h4 class="card-title">Animal Farm</h4>
          <h6 class="text-muted">George Orwell</h6>
          <p class="card-text">Tired of their servitude to man, a group of farm animals revolt and establish their own society, only to be betrayed into worse servitude by their leaders, the pigs. This satire addresses the communist philosophy the Soviet Union.</p>
          <a href="#" class="btn btn-primary">Read more</a>
        </div>
      </article><!-- .end Card -->
    </div>
    <div class="col-xs-12 col-md-4">
      <!-- Card -->
      <article class="card animated fadeInUp">
        <div class="card-block">
          <h4 class="card-title">Life After Life</h4>
          <h6 class="text-muted">Kate Atkinson</h6>
        </div>
        <img class="img-responsive" src="https://snap-photos.s3.amazonaws.com/img-thumbs/960w/SYC0YBA37V.jpg" alt="Leaf on the street" />
        <div class="card-block">
          <p class="card-text">On a cold and snowy night, Ursula Todd is born, the 3rd child of a wealthy banker and his wife. She dies before she can draw her first breath. On that same cold and snowy night, lets out a lusty wail.</p>
        </div>
        <div class="card-block text-center">
          <div class="btn-group hidden-sm-down hidden-md-down" role="group" aria-label="Card buttons">
            <a href="#" class="btn btn-primary">Read more</a>
            <a href="#" class="btn btn-primary">Save for later</a>
          </div>
          <div class="btn-group-vertical hidden-lg-up" role="group" aria-label="Card buttons">
            <a href="#" class="btn btn-primary">Read more</a>
            <a href="#" class="btn btn-primary">Save for later</a>
          </div>
        </div>
      </article><!-- .end Card -->
    </div>
    <div class="col-xs-12 col-md-4">
      <!-- Card -->
      <article class="card animated fadeInRight">
        <div class="card-block">
          <h4 class="card-title">Wind, Sand and Stars</h4>
          <h6 class="text-muted">Antoine de Saint-Exupéry</h6>
          <p class="card-text">Story that captures the grandeur, danger, and isolation of flight. Its exciting account of air adventure, combined with lyrical prose and the spirit of a philosopher, makes it one of the most popular works ever written.</p>
        </div>
        <div class="card-block text-center">
          <div class="btn-group hidden-sm-down hidden-md-down" role="group" aria-label="Card buttons">
            <a href="#" class="card-link">Read more</a>
            <a href="#" class="card-link">Save for later</a>
          </div>
          <div class="btn-group-vertical hidden-lg-up" role="group" aria-label="Card buttons">
            <a href="#" class="card-link">Read more</a><br />
            <a href="#" class="card-link">Save for later</a>
          </div>
        </div>
        <img class="card-img-bottom img-responsive" src="https://snap-photos.s3.amazonaws.com/img-thumbs/960w/8SALDQRRZX.jpg" alt="White sand" />
      </article><!-- .end Card -->
    </div>
  </div><!-- .end First row -->
  <!-- Second row -->
  <div class="row m-t-md">
    <div class="col-xs-12 col-md-4">
      <!-- Card -->
      <article class="card card-inverse animated fadeInLeft">
        <img class="img-responsive" src="https://snap-photos.s3.amazonaws.com/img-thumbs/960w/1U2EGZ07GU.jpg" alt="Deer in nature" />
        <div class="card-img-overlay">
          <h4 class="card-title">Animal Farm</h4>
          <h6 class="text-muted">George Orwell</h6>
          <p class="card-text">Tired of their servitude to man, a group of farm animals revolt and establish their own society...</p>
        </div>
      </article><!-- .end Card -->
    </div>
    <div class="col-xs-12 col-md-4">
      <!-- Card -->
      <article class="card card-inverse animated fadeInDown">
        <img class="img-responsive" src="https://snap-photos.s3.amazonaws.com/img-thumbs/960w/SYC0YBA37V.jpg" alt="Leaf on the street" />
        <div class="card-img-overlay">
          <h4 class="card-title">Life After Life</h4>
          <h6 class="text-muted">Kate Atkinson</h6>
          <p class="card-text">On a cold and snowy night, Ursula Todd is born, the 3rd child of a wealthy banker and his wife. She die...</p>
        </div>
      </article><!-- .end Card -->
    </div>
    <div class="col-xs-12 col-md-4">
      <!-- Card -->
      <article class="card card-inverse animated fadeInRight">
        <img class="img-responsive" src="https://snap-photos.s3.amazonaws.com/img-thumbs/960w/8SALDQRRZX.jpg" alt="White sand" />
        <div class="card-img-overlay">
          <h4 class="card-title">Wind, Sand and Stars</h4>
          <h6 class="text-muted">Antoine de Saint-Exupéry</h6>
          <p class="card-text">Story that captures the grandeur, danger, and isolation of flight. Its exciting account of air adventure...</p>
        </div>
      </article><!-- .end Card -->
    </div>
  </div><!-- .end Second row -->
</div>
!

CSS 

              
                // Box shadow helper
@mixin BoxShadowHelper($level: 1){
  @if $level == 1 {
    box-shadow: 0 2px 5px 0 rgba(0, 0, 0, .16), 0 2px 10px 0 rgba(0, 0, 0, .12);
  }
  @if $level == 2 {
    box-shadow: 0 5px 11px 0 rgba(0, 0, 0, .18), 0 4px 15px 0 rgba(0, 0, 0, .15);
  }
}
a {transition: .25s all;}
.card {
  overflow: hidden;
  @include BoxShadowHelper(1);
  transition: .25s box-shadow;
  &:focus,
  &:hover {@include BoxShadowHelper(2);}
}
.card-inverse .card-img-overlay {
  background-color: rgba(#333,.85);
  border-color: rgba(#333,.85);
}
!

JS 

              
                /**
 * Check out the tutorial on:
 * 
 */
!
999px

Console