.vertical-timeline * {
  box-sizing: border-box;
}

.vertical-timeline {
  width: 95%;
  max-width: 1170px;
  margin: 2em auto;
  position: relative;
  padding: 2em 0;
}
.vertical-timeline::after {
  /* clearfix */
  content: '';
  display: table;
  clear: both;
}

.vertical-timeline::before {
  /* this is the vertical line */
  content: '';
  position: absolute;
  top: 0;
  left: 18px;
  height: 100%;
  width: 4px;
  background: white;
}

@media only screen and (min-width: 1170px) {
  .vertical-timeline.vertical-timeline--two-columns {
    margin-top: 3em;
    margin-bottom: 3em;
    width: 90%;
  }
  .vertical-timeline.vertical-timeline--two-columns:before {
    left: 50%;
    margin-left: -2px;
  }
}

.vertical-timeline * {
  box-sizing: border-box;
}

.vertical-timeline {
  width: 95%;
  max-width: 1170px;
  margin: 0 auto;
  position: relative;
  padding: 2em 0;
}
.vertical-timeline::after {
  /* clearfix */
  content: '';
  display: table;
  clear: both;
}

.vertical-timeline::before {
  /* this is the vertical line */
  content: '';
  position: absolute;
  top: 0;
  left: 18px;
  height: 100%;
  width: 4px;
  background: white;
}

@media only screen and (min-width: 1170px) {
  .vertical-timeline.vertical-timeline--two-columns {
    width: 90%;
  }
  .vertical-timeline.vertical-timeline--two-columns:before {
    left: 50%;
    margin-left: -2px;
  }
}

Remove timeline wrapper margin top and margin bottom
Remove timeline wrapper margin top and margin bottom
