* {
  box-sizing: border-box;
}

html, body {
  width: 100%;
  height: 100%;
  margin: 0;
}

.timeline {
  width: 100%;
  padding: 20px;
  position: relative;
  box-sizing: border-box;
  background: #0099FF;
  max-width: 800px;
  margin: 10px auto;
}

.timeline:before {
  position: absolute;
  width: 4px;
  height: calc(100% - 40px);
  background: #FFF;
  content: "";
  left: calc(50% - 2px);
}

.timieline-title {
  font-size: 1.5em;
  font-weight: bold;
}

.timeline-content {
  width: calc(50% - 70px);
  padding: 20px;
  background: #FFF;
  position: relative;
  left: 20px;
  min-height: 100px;
  border-radius: 10px;
  margin-top: 10px;
  box-shadow: 0px 0px 2px 2px rgba(0, 0, 0, 0.2);
}

.timeline-content:before {
  width: 20px;
  height: 20px;
  content: "";
  text-align: center;
  font-weight: bold;
  background: #FFF;
  position: absolute;
  right: -60px;
  border-radius: 50%;
  top: calc(50% - 10px);
  box-sizing: border-box;
  box-shadow: 0px 0px 2px 2px rgba(0, 0, 0, 0.2);
}

.timeline-content:after {
  content: "";
  left: 100%;
  width: 50px;
  border-top: 2px dashed #FFF;
  position: absolute;
  top: calc(50% - 1px);
}

.timeline-period {
  left: calc(100% + 70px);
  position: absolute;
  display: inline-block;
  background: #FFF;
  padding: 10px;
  white-space: nowrap;
  border-radius: 10px;
  top: calc(50% - 19px);
  font-style: italic;
  font-size: 0.9em;
  font-weight: bold;
  color: #666;
  box-shadow: 0px 0px 2px 2px rgba(0, 0, 0, 0.2);
}

.timeline-period:before {
  content: "";
  left: -18px;
  width: 6px;
  border: 6px dashed transparent;
  position: absolute;
  top: calc(50% - 6px);
  border-right: 6px solid #FFF;
}

@media screen and (min-width: 1024px) {
  .timeline-content:nth-child(even) {
    left: calc(50% + 50px);
  }

  .timeline-content:nth-child(even):before {
    right: auto;
    left: -60px;
  }

  .timeline-content:nth-child(even):after {
    right: auto;
    left: -50px;
  }

  .timeline-content:nth-child(even) .timeline-period {
    right: calc(100% + 70px);
    left: auto;
  }

  .timeline-content:nth-child(even) .timeline-period:before {
    left: 100%;
    border-right-color: transparent;
    border-left-color: #FFF;
  }
}