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Adding Classes

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CSS

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HTML 

              
                <div class="container">
  <section class="scroller">
    <p><a class="scroll-link scroll-to-last" href="#last">Scroll to last section <span class="scroll-link__icon">⬇</span></a></p>
    
    <h1 class="main-title" id="first">Chapter 1: Down the Rabbit-Hole</h1>
    
    <p>Alice was beginning to get very tired of sitting by her sister on the bank, and of having nothing to do: once or twice she had peeped into the book her sister was reading, but it had no pictures or conversations in it, &ldquo;and what is the use of a book,&rdquo; thought Alice &ldquo;without pictures or conversation?&rdquo;
    </p>
    <p>
      So she was considering in her own mind (as well as she could, for the hot day made her feel very sleepy and stupid), whether the pleasure of making a daisy-chain would be worth the trouble of getting up and picking the daisies, when suddenly a White Rabbit with pink eyes ran close by her.
    </p>
    
    <p>
      Lorem ipsum dolor sit amet, consectetur adipisicing elit. Molestias incidunt animi laborum? Sequi commodi facere nemo quibusdam, vero libero eos, saepe explicabo, fugiat ea quis, animi molestias eaque consectetur voluptatibus!
    </p>
    
    <p>
      Lorem ipsum dolor sit amet, consectetur adipisicing elit. Eos est ullam eaque non qui illo possimus molestias quibusdam, repudiandae incidunt a praesentium necessitatibus voluptas repellat itaque ad id rerum. Architecto.
    </p>
    
    <p>
      Lorem ipsum dolor sit amet, consectetur adipisicing elit. Est adipisci error assumenda molestiae tempore. Delectus autem, doloribus magni reiciendis a eligendi incidunt enim dolores vel, eos voluptate aut maxime, voluptatum.
    </p>
    
    <h2 class="secondary-heading" id="last">Last Section</h2>
    
    <p>
      She ate a little bit, and said anxiously to herself, &ldquo;Which way? Which way?&rdquo;, holding her hand on the top of her head to feel which way it was growing, and she was quite surprised to find that she remained the same size: to be sure, this generally happens when one eats cake, but Alice had got so much into the way of expecting nothing but out-of-the-way things to happen, that it seemed quite dull and stupid for life to go on in the common way.
    </p>
    
    <p>So she set to work, and very soon finished off the cake.</p>
    
    <div class="separator">
      <span class="separator__icons">❖❖❖❖❖</span>
    </div>
    
    <p>
      <a class="scroll-link scroll-to-first" href="#first">Scroll to first section <span class="scroll-link__icon">⬆</span></a>
    </p>
  </section>
</div>
!

CSS 

              
                @import url('https://fonts.googleapis.com/css?family=Macondo');
* {
  box-sizing: border-box;
}
*:after,
*:before {
  box-sizing: inherit;
}
body {
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
  overflow-x: hidden;
  font-size: 16px;
  line-height: 1.5;
  color: #333;
}
.container {
  width: 100%;
  height: 100vh;
  margin: 0 auto;
  position: relative;
}

.scroller {
  position: relative;
  width: 80%;
  max-width: 800px;
  max-height: 500px;
  overflow-y: scroll;
  overflow-x: hidden;
  margin: 0 auto;
  padding: 0 1.5em 2em;
  border: 2px solid red;
}

.main-title,
.secondary-heading {
  color: #444;
  text-align: center;
  font-family: 'Macondo', cursive;
}

.main-title {
  font-size: 1.6em;
  line-height: 1.1;
  margin-top: 2em;
}

.scroll-link {
  display: block;
  text-decoration: none;
  position: relative;
  padding: 0.5em;
  font-size: 1.2em;
  transform: scale(1.1);
  color: red;
  text-align: center;
  transition: transform 0.5s;
}

.scroll-link::after {
  content: "";
  display: block;
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0.3em;
  left: 0;
  border: 1px solid transparent;
  border-bottom: 1px solid red;
  transition: border-width 0.7,
              border-color 0.5s;
          
}

.scroll-link:hover,
.croll-link:focus {
  transform: scale(1);
}

.scroll-link:hover:after,
.croll-link:focus:after {
  border-color: red;
  border-width: 2px;
}

.scroll-link__icon {
  font-size: 2em;
}

.separator {
  margin: 0 auto;
  text-align: center;
}

.separator__icons {
  font-size: 1.5em;
  color: red;
}

/* Media Queries */
@media screen and (min-width: 800px) {
  .container {
    max-width: 80%;
  }
  
  .scroll-link {
    max-width: 50%;
    margin: 0 auto;
    text-wrap: nowrap;
  }
}
!

JS 

              
                //Scrolls page up or down
const scrolling = (element, container, direction) => {
  let offsetDistance = 0;
  /* Ternary operator: if the value of 'direction' is 'up' 
  the page will be offset -200px above the element that is 
  being scrolled into view, otherwise the value will be 200px, which 
  offsets the page 200px below the element scrolled into view */
  direction === 'up' ? offsetDistance = -200 : 200;
  Velocity(element, 'scroll', {
    container: container, 
    duration: 500, 
    offset: offsetDistance, 
    easing: 'ease-out'
  }); 
};

const scrollerContainer = document.querySelector('.scroller');
//links
const scrollToFirst = document.querySelector('.scroll-to-first');
const scrollToLast = document.querySelector('.scroll-to-last');
//sections to scroll to
const firstSection = document.querySelector('#first');
const lastSection = document.querySelector('#last');

/*Handlers for Scroll to Last Section and Scroll to First Section links */
scrollToLast.addEventListener('click', (e) => {
  e.preventDefault();
  scrolling(lastSection, scrollerContainer, 'down');
});

scrollToFirst.addEventListener('click', (e) => {
  e.preventDefault();
  scrolling(firstSection, scrollerContainer, 'up');
});
!
999px

Console