JSFiddle - React, Tailwind, and code Playground

by Rafael Cheruti

HTML

<section class="intro">
  <div class="container">
    <h1>Vertical Timeline &darr;</h1>
    <button onclick="processar()">update</button>
  </div>
</section>

<section class="timeline">
  <ul>
    <li id='elem1'>
      <div>
        <time>1934</time> At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium
      </div>
    </li>
    <li id="elem2">
      <div>
        <time>1937</time> Proin quam velit, efficitur vel neque vitae, rhoncus commodo mi. Suspendisse finibus mauris et bibendum molestie. Aenean ex augue, varius et pulvinar in, pretium non nisi.
      </div>
    </li>
    <li id="elem3">
      <div>
        <time>1940</time> Proin iaculis, nibh eget efficitur varius, libero tellus porta dolor, at pulvinar tortor ex eget ligula. Integer eu dapibus arcu, sit amet sollicitudin eros.
      </div>
    </li>
    <li id="elem4">
      <div>
        <time>1943</time> In mattis elit vitae odio posuere, nec maximus massa varius. Suspendisse varius volutpat mattis. Vestibulum id magna est.
      </div>
    </li>
    <li id="elem5">
      <div>
        <time>1946</time> In mattis elit vitae odio posuere, nec maximus massa varius. Suspendisse varius volutpat mattis. Vestibulum id magna est.
      </div>
    </li>
    <li id="elem6">
      <div>
        <time>1956</time> In mattis elit vitae odio posuere, nec maximus massa varius. Suspendisse varius volutpat mattis. Vestibulum id magna est.
      </div>
    </li>
    <li id="elem7">
      <div>
        <time>1957</time> In mattis elit vitae odio posuere, nec maximus massa varius. Suspendisse varius volutpat mattis. Vestibulum id magna est.
      </div>
    </li>
    <li id="elem8">
      <div>
        <time>1967</time> Aenean condimentum odio a bibendum rhoncus. Ut mauris felis, volutpat eget porta faucibus, euismod quis ante.
      </div>
    </li>
  </ul>
</section>

CSS

*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font: normal 16px/1.5 "Helvetica Neue", sans-serif;
  background: #ffffff;
  color: #404040;
  overflow-x: hidden;
  padding-bottom: 50px;
}  


/* INTRO SECTION
–––––––––––––––––––––––––––––––––––––––––––––––––– */

.intro {
  background: #FFFFFF;
  padding: 100px 0;
}

.container {
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
  text-align: center;
}

h1 {
  font-size: 2.5rem;
}


/* TIMELINE
–––––––––––––––––––––––––––––––––––––––––––––––––– */
.timeline ul li {
  list-style-type: none;
  position: relative;
  width: 6px;
  margin: 0 auto;
  padding-top: 50px;
  background: #404040;
}

.timeline ul li::after {
  content: '';
  position: absolute;
  left: 50%;
  bottom: 0;
  transform: translateX(-50%);
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: inherit;
}

.timeline ul li div {
  position: relative;
  bottom: 0;
  width: 400px;
  padding: 15px;
  background: #FFFFFF;
}

.timeline ul li div::before {
  content: '';
  position: absolute;
  bottom: 7px;
  width: 0;
  height: 0;
  border-style: solid;
}

.timeline ul li:nth-child(odd) div {
  left: 45px;
}

.timeline ul li:nth-child(odd) div::before {
  left: -15px;
  border-width: 8px 16px 8px 0;
  border-color: transparent transparent transparent transparent;
}

.timeline ul li:nth-child(even) div {
  left: -439px;
}

.timeline ul li:nth-child(even) div::before {
  right: -15px;
  border-width: 8px 0 8px 16px;
    border-color: transparent transparent transparent transparent;
}

/* LEFT JUSTIFY
–––––––––––––––––––––––––––––––––––––––––––––––––– */

.timeline ul li {
    margin-left: 20px;
  }
  
  .timeline ul li div {
    width: calc(100vw - 91px);
  }
  
  .timeline ul li:nth-child(even) div {
    left: 45px;
  }
  
  .timeline ul li:nth-child(even) div::before {
    left: -15px;
    border-width: 8px 16px 8px 0;

  }
  .timeline ul li.newstyle::after {
    background:#3887be;
   }

JavaScript

function processar() {
	var myArr = ['elem1', 'elem3', 'elem8'];

  for (var i = 0; i < myArr.length; i++) { // "i" is the index!
    var elem = document.getElementById( myArr[i] ); // "myArr[i]" to get the item
    elem.className += ' newstyle';
  }
}