Mobile First Vertical Timeline In JavaScript

Preview:

Description:

A responsive, mobile-first, SEO-friendly, Material Design styled timeline to present your events, tasks, milestone, stories, and much more.

How to use it:

The HTML structure for the timeline. Insert your own event data (titles, descriptions, actions buttons, start/end dates, etc.) as follows:

<div class="timeline">
  <div class="timeline__bar"></div>
  <div class="timeline__elem timeline__elem--left">
    <div class="timeline__date"><span class="timeline__date-day">10</span><span class="timeline__date-month">Jul</span></div>
    <div class="timeline__event">
      <div class="timeline__event-date-time">
        <div class="timeline__event-date"> <span>10/07/2019</span></div>
        <div class="timeline__event-time"><span>12:30</span></div>
      </div>
      <h4 class="timeline__event-title">Event 1</h4>
      <div class="timeline__event-descr">
        <p>Event 1 Description</p>
      </div>
      <div class="timeline__event-actions"><a class="timeline__event-action" href="#" title="Learn More">Learn More </a><a class="timeline__event-action" href="#" title="Contact Us">Contact Us</a></div>
    </div>
  </div>
  <div class="timeline__elem timeline__elem--right">
    <div class="timeline__date"><span class="timeline__date-day">18</span><span class="timeline__date-month">Jul</span></div>
    <div class="timeline__event">
      <div class="timeline__event-date-time">
        <div class="timeline__event-date"> <span>18/07/2019</span></div>
        <div class="timeline__event-time"><span>12:30</span></div>
      </div>
      <h4 class="timeline__event-title">Event 2</h4>
      <div class="timeline__event-descr">
        <p>Event 2 Description</p>
      </div>
      <div class="timeline__event-actions"><a class="timeline__event-action" href="#" title="Learn More">Learn More </a><a class="timeline__event-action" href="#" title="Contact Us">Contact Us</a></div>
    </div>
  </div>
</div>

The necessary CSS for the timeline. Copy and paste the following CSS snippets into your page.

.timeline {
  position: relative;
  min-height: 500px;
  width: 100%;
  padding: 60px 0;
}
.timeline__bar {
  position: absolute;
  top: 0;
  left: 50%;
  width: 6px;
  height: 100%;
  -webkit-transform: translateX(-50%);
          transform: translateX(-50%);
  background-image: linear-gradient(#ffce79, #9b74ff);
}
.timeline__bar:before, .timeline__bar:after {
  position: absolute;
  left: 50%;
  display: block;
  width: 12px;
  height: 12px;
  content: '';
  -webkit-transform: translateX(-50%);
          transform: translateX(-50%);
  border-radius: 50%;
}
.timeline__bar:before {
  top: -1px;
  background-color: #ffce79;
}
.timeline__bar:after {
  bottom: -1px;
  background-color: #9b74ff;
}
.timeline__elem {
  position: relative;
  display: flex;
  flex-direction: column;
  margin-bottom: 30px;
}
.timeline__elem:last-child {
  margin-bottom: 0;
}
@media (min-width: 900px) {
  .timeline__elem {
    flex-direction: row;
  }
}
@media (min-width: 900px) {
  .timeline__elem--right {
    justify-content: flex-end;
  }
}
.timeline__date {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 70px;
  height: 70px;
  margin: auto;
  color: #fff;
  background-repeat: no-repeat;
  border-radius: 50%;
  border: 6px solid #fff;
}
@media (min-width: 900px) {
  .timeline__date {
    position: absolute;
    top: 50%;
    left: 50%;
    -webkit-transform: translate(-50%, -50%);
            transform: translate(-50%, -50%);
  }
}
.timeline__date-day {
  font-size: 1.35rem;
  font-weight: 600;
}
.timeline__date-month {
  font-size: .85rem;
}
.timeline__event {
  position: relative;
  width: 90%;
  margin: 30px auto 0;
  box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.14), 0 3px 1px -2px rgba(0, 0, 0, 0.12), 0 1px 5px 0 rgba(0, 0, 0, 0.2);
  background-color: #fff;
}
@media (min-width: 560px) {
  .timeline__event {
    width: 65%;
  }
}
@media (min-width: 900px) {
  .timeline__event {
    width: calc((100% - 70px - 8px * 4) / 2);
    margin: 0;
  }
}
.timeline__event:before {
  position: absolute;
  top: 50%;
  display: none;
  width: 0;
  height: 0;
  content: '';
  -webkit-transform: translateY(-50%);
          transform: translateY(-50%);
  border-top: 8px solid transparent;
  border-bottom: 8px solid transparent;
}
.timeline__event:after {
  position: absolute;
  top: 50%;
  display: none;
  width: 16px;
  height: 16px;
  content: '';
  -webkit-transform: translateY(-50%) rotate(45deg);
          transform: translateY(-50%) rotate(45deg);
}
@media (min-width: 900px) {
  .timeline__event:before, .timeline__event:after {
    display: block;
  }
}
.timeline__event--left:before {
  right: -8px;
  border-left: 8px solid #fff;
}
.timeline__event--left:after {
  right: -7px;
  box-shadow: 2px -1px 1px 0 rgba(0, 0, 0, 0.08);
}
.timeline__event--right:before {
  left: -8px;
  border-right: 8px solid #fff;
}
.timeline__event--right:after {
  left: -7px;
  box-shadow: -2px 2px 1px 0 rgba(0, 0, 0, 0.08);
}
.timeline__event-date-time {
  padding: 20px 15px 0;
  display: flex;
  margin-bottom: 15px;
  font-size: .8rem;
  color: rgba(44, 44, 44, 0.7);
}
.timeline__event-date {
  margin-right: 10px;
}
.timeline__event-title {
  padding: 0 15px;
  margin-bottom: 15px;
  font-size: 1.25rem;
  font-weight: 600;
}
.timeline__event-descr {
  padding: 0 15px 20px;
  font-size: .9rem;
  line-height: 1rem;
}
.timeline__event-descr p {
  margin-bottom: 10px;
}
.timeline__event-descr p:last-child {
  margin-bottom: 0;
}
.timeline__event-actions {
  padding: 20px 15px;
  border-top: 1px solid rgba(160, 160, 160, 0.2);
}
.timeline__event-action {
  transition-property: all;
  transition-duration: 0.2s;
  transition-timing-function: linear;
  transition-delay: 0s;
  margin-right: 24px;
  font-size: .9rem;
  text-transform: uppercase;
}
.timeline__event-action:hover {
  opacity: .4;
}

The JavaScript to enable the timeline.

//DOM STRINGS OBJECT
const DOM = {
  timelineDate: document.querySelectorAll('.timeline__date'),
  timelineElem: document.querySelectorAll('.timeline__elem'),
  timelineBar: document.querySelector('.timeline__bar')
};
//TIMELINE ELEM SET DIRECTION TO EVENT ITEMS (left or right oriented)
//getting direction from .timeline-elem
const __getDir = timelineElem => {
  
  if (timelineElem.classList.contains('timeline__elem--left')) {
    return 'left'
  } else if (timelineElem.classList.contains('timeline__elem--right')) {
    return 'right'
  }
  
};
const setDirEvent = () => {
  
  DOM.timelineElem.forEach(elem => {
    
    const direction = __getDir(elem);
    
    const timelineEvent = elem.querySelector('.timeline__event');
    
    timelineEvent.classList.add(`timeline__event--${direction}`);
    
  });
  
};
//TIMELINE ELEM DATE STYLES (background)
const __getBGImage = () => {
  
  const compStyle = getComputedStyle(DOM.timelineBar);
  
  return compStyle.backgroundImage;
  
};
const __getBGSize_height = () => {
  
  const timebarHeight = DOM.timelineBar.offsetHeight;
  
  return timebarHeight;
  
}
const __getBGPos_y = (dateElem) => {
  
  const timelinebarBox = DOM.timelineBar.getBoundingClientRect();
  
  const dateBox = dateElem.getBoundingClientRect();
  
  const pos_y = dateBox.top - timelinebarBox.top;
  
  return pos_y;
  
}
const setDateBG = () => {
  
  const bgImg = __getBGImage();
  
  const bgHeight = __getBGSize_height();
  
  DOM.timelineDate.forEach(elem => {
    
    //setting bgImage
    elem.style.backgroundImage = bgImg;
    
    //setting bgSize
    elem.style.backgroundSize = `100% ${bgHeight}px`;
    
    //setting bgPosition
    const dateOffset = __getBGPos_y(elem);
    
    elem.style.backgroundPosition = `0 -${dateOffset}px`;
    
  });
  
};
//ONLOAD FUNCTION
window.addEventListener('load', () => {
  
  //setting direction class to the timeline event block
  setDirEvent();
  
  //set date background styles
  setDateBG();
  
});