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HTML

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Adding Classes

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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 

              
                <nav>
  <a href="#Home">Home</a>
  <a href="#About">About</a>
  <a href="#Features">Features</a>
  <a href="#ContactUs">Contact Us</a>
</nav>

<div class="content">
  <section id="Home">
    <h3>Home</h3>
    Lorem ipsum dolor sit amet, consectetur adipisicing elit. Sunt nemo eveniet repellendus dicta cum quas veniam! Quod, possimus. Ullam eum aspernatur quis sequi, at, laudantium doloremque nulla voluptatum ducimus debitis molestiae, cupiditate fuga magni commodi maiores harum accusamus repudiandae amet suscipit autem labore minus ad. Ipsam eligendi, repellat voluptatem nostrum veniam at sapiente minima vero iure, esse architecto vel perferendis eveniet nemo vitae cupiditate laboriosam quas omnis quidem! Laudantium, perferendis explicabo commodi, non fugit sit! Laborum deleniti illo ratione voluptates. Dignissimos quo non maxime autem delectus ex minus voluptas veritatis esse ea, repellendus, ratione repellat fuga enim explicabo dolor tempore?
  </section>
  <section id="About">
    <h3>About</h3>
  Lorem ipsum dolor sit amet, consectetur adipisicing elit. Quia repudiandae nostrum quae unde voluptatibus adipisci, ipsa, consequuntur, explicabo ullam quo iusto fugit, nemo ex totam. Omnis temporibus incidunt libero reiciendis illo mollitia rem odit nam pariatur voluptates ratione fugiat officiis similique, quia magni, molestias nihil exercitationem perspiciatis repudiandae iste. Natus!
  </section>
  <section id="Features">
    <h3>Features</h3>
    Lorem ipsum dolor sit amet, consectetur adipisicing elit. Sunt nemo eveniet repellendus dicta cum quas veniam! Quod, possimus. Ullam eum aspernatur quis sequi, at, laudantium doloremque nulla voluptatum ducimus debitis molestiae, cupiditate fuga magni commodi maiores harum accusamus repudiandae amet suscipit autem labore minus ad. Ipsam eligendi, repellat voluptatem nostrum veniam at sapiente minima vero iure, esse architecto vel perferendis eveniet nemo vitae cupiditate laboriosam quas omnis quidem! Laudantium, perferendis explicabo commodi, non fugit sit! Laborum deleniti illo ratione voluptates. Dignissimos quo non maxime autem delectus ex minus voluptas veritatis esse ea, repellendus, ratione repellat fuga enim explicabo dolor tempore?
  </section>
  <section id="ContactUs">
    <h3>Contact Us</h3>
  Lorem ipsum dolor sit amet, consectetur adipisicing elit. Quia repudiandae nostrum quae unde voluptatibus adipisci, ipsa, consequuntur, explicabo ullam quo iusto fugit, nemo ex totam. Omnis temporibus incidunt libero reiciendis illo mollitia rem odit nam pariatur voluptates ratione fugiat officiis similique, quia magni, molestias nihil exercitationem perspiciatis repudiandae iste. Natus!
  </section>
</div>
!

CSS 

              
                @import url(https://fonts.googleapis.com/css?family=Open+Sans:300,400,600,700,800);

@mixin animation($animation) {
  -webkit-animation: $animation;
  -moz-animation: $animation;
  animation: $animation;
}
@mixin keyframes($name, $name1) {
  @-webkit-keyframes #{$name} {
    @content;
  }
  @-moz-keyframes #{$name} {
    @content;
  }
  @-ms-keyframes #{$name} {
    @content;
  }
  @keyframes #{$name} {
    @content;
  }
}

/* demo styles */

@import url(https://fonts.googleapis.com/css?family=Open+Sans:400,600,700,800);
body {
  background-color: #2c3e50;
  padding: 50px;
  color: #fff;
  text-align: center;
  font-family: 'Open Sans', sans-serif;
  vertical-align: middle;
  line-height: 1.555;
}

h3 {
  font-size: 20px;
  margin-top: 0;
  margin-bottom: 10px;
}

::-webkit-input-placeholder{
  color: #3e7b77;
  text-transform: uppercase;
}
::-moz-placeholder {  /* Firefox 19+ */
  color: #3e7b77;
  text-transform: uppercase; 
}
/* end styles */

nav{
  font-size: 0;
  display: inline-block;
  margin-bottom: 15px;
  a{
    display: inline-block;
    background-color: #fff;
    padding: 10px 20px;
    font-size: 14px;
    color: #fb3c3c;
    font-weight: 600;
    text-decoration: none;
    margin: 0 1px;
    border-bottom: solid 3px #fb3c3c;
  }
}
.content{
  width: 400px;
  color: #fff;
  font-size: 14px;
  margin: auto;
  text-align: justify;
  section{
    margin-bottom: 20px;
    padding: 10px;
  }
}

section:target{
  background-color: rgba(#fff, 0);
  border-left: solid 5px orange;
  @include animation(bgColor 1s linear );
}

@include keyframes(bgColor, bgColor animation) {
  0%{
    background-color: rgba(#fff, .8);
  }
  100%{
    background-color: rgba(#fff, 0);
  }
}
!

JS
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