How do I get a page to resize without element to change

When open my page on mobile the screen look different. I am trying to create timeline page but for some how when I change the screen size the timeline also change.

Why?

Please see attached the different between mobile and desktop page. Fit to screen

CSS:

.container-style {
  max-width: 1300px;
  max-height: auto;
  overflow: hidden;
  margin: 30px auto 0;
  box-shadow: 0 0 20px #a0a0a0;
}

.timeline ul {
  padding: 1em 0 0 2em;
  list-style: none;
  position: relative;
  margin: 0 auto;
}

.timeline ul::before {
  content: ' ';
  height: 100%;
  width: 2px;
  background-color: #000;
  position: absolute;
  z-index: -1;
  top: 0;
  bottom: 0;
  left: 24%;
  display: block;
}

.timeline li div {
  display: inline-block;
  vertical-align: top;
}

.timeline .bullet {
  width: 3em;
  height: 3em;
  box-sizing: border-box;
  border-radius: 50%;
  background: #F93B69;
  z-index: 1;
  margin-top: 110px;
  top: 0;
  bottom: 0;
}


.timeline .time {
  width: 20%;
  font-size: 2.0em;
  margin-top: 120px;
  color: #F93B69;
  font-weight: bold;
  display: inline-block;
}

.timeline .desc {
  width: 50%;
  padding-top: .90em;
  margin-left: 25px;
}