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HTML

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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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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 

              
                <h2>Columns example</h2>
<div class="features">
  <article>
    <h3>Lorem ipsum</h3>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Error aperiam consectetur quasi ratione quas assumenda accusamus sapiente exercitationem suscipit distinctio ipsum excepturi dolorum sint cum hic illo mollitia asperiores unde?</p>
  </article>
  <article>
    <h3>Lorem ipsum</h3>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Error aperiam consectetur quasi ratione quas assumenda accusamus sapiente exercitationem suscipit distinctio ipsum excepturi dolorum sint cum hic illo mollitia asperiores unde?</p>
  </article>
  <article>
    <h3>Lorem ipsum</h3>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Error aperiam consectetur quasi ratione quas assumenda accusamus sapiente exercitationem suscipit distinctio ipsum excepturi dolorum sint cum hic illo mollitia asperiores unde?</p>
  </article>
</div>

<h2>Vertical align example</h2>
<div class="products">
  <article>
    <h3>Lorem ipsum</h3>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Necessitatibus dolor odit nihil beatae tempore vitae ad perspiciatis libero eligendi rerum quae suscipit fugit aspernatur reprehenderit quisquam provident deserunt minima consequuntur.</p>
  </article>
  
  <article>
    <h3>Lorem ipsum</h3>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit.</p>
  </article>
  
  <article>
    <h3>Lorem ipsum</h3>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Necessitatibus dolor odit nihil beatae tempore vitae ad perspiciatis libero eligendi rerum quae suscipit fugit aspernatur reprehenderit quisquam provident deserunt minima consequuntur.</p>
  </article>
</div>

<h2>Fluid example</h2>
<div class="compare">
  <article class="fluid">
    <h3>Lorem ipsum</h3>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Obcaecati harum quisquam ut illo iste velit cumque tempore eligendi eveniet debitis incidunt vitae illum ducimus magnam fugiat dicta nemo nihil quaerat.</p>
  </article>
  <article class="fluid">
    <h3>Lorem ipsum</h3>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Officia corrupti quas libero aliquid consequuntur necessitatibus molestiae harum ea eaque placeat nobis voluptatibus tempora et cumque delectus numquam at ratione non!</p>
  </article>
</div>
!

CSS 

              
                @import "compass/css3";

// Make sure you have this in your styles
// because grid is using paddings
*, *:before, *:after {
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}

// This is mixin which you will include in parent
// of columns. It kills default margin of inline-block
// elements.
@mixin row () {
  font-size: 0;
}

// This is column mixins.
@mixin col ($col, $sum, $gap: 1em, $align: top, $first: false, $last: false) {
    width: 100%;
    display: inline-block;
    font-size: 16px;
    padding-left: if($first, 0, $gap);
    padding-right: if($last, 0, $gap);

    @media only screen and (min-width: 768px) {
            width: percentage($col/$sum);
            vertical-align: $align;
    }

    &.fluid { width: percentage($col/$sum); }
}

h2 { margin-top: 0; }

.features, .products, .compare {
  @include row;
  margin-bottom: 50px;
}

.features article {
  @include col(1, 3);
}

.products article {
  background: #eee;
  @include col(1, 3, $align: middle);
}

.compare article {
  @include col(1, 2);
}
!

JS
!
999px

Console