body {
  font-family: Verdana;
  font-size: 12px;
  line-height: 1.5;
}

#timeline {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  background-color: #000000;
}
#timeline:hover .tl-item {
  width: 23.3333%;
}

.tl-item {
  -webkit-transform: translate3d(0, 0, 0);
          transform: translate3d(0, 0, 0);
  position: relative;
  width: 25%;
  height: 100vh;
  min-height: 1000px;
  color: #fff;
  overflow: hidden;
  -webkit-transition: width 0.5s ease;
  transition: width 0.5s ease;
}
.tl-item:before, .tl-item:after {
  -webkit-transform: translate3d(0, 0, 0);
          transform: translate3d(0, 0, 0);
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
}
.tl-item:after {
  background: rgba(3, 22, 37, 0.85);
  opacity: 1;
  -webkit-transition: opacity 0.5s ease;
  transition: opacity 0.5s ease;
}
.tl-item:before {
  background: -webkit-linear-gradient(top, transparent 0%, black 40%);
  background: linear-gradient(to bottom, transparent 0%, black 60%);
  z-index: 1;
  opacity: 0;
  -webkit-transform: translate3d(0, 0, 0) translateY(50%);
          transform: translate3d(0, 0, 0) translateY(50%);
  -webkit-transition: opacity 0.5s ease, -webkit-transform 0.5s ease;
  transition: opacity 0.5s ease, -webkit-transform 0.5s ease;
  transition: opacity 0.5s ease, transform 0.5s ease;
  transition: opacity 0.5s ease, transform 0.5s ease, -webkit-transform 0.5s ease;
}
.tl-item:hover {
  width: 30% !important;
}
.tl-item:hover:after {
  opacity: 0;
}
.tl-item:hover:before {
  opacity: 1;
  -webkit-transform: translate3d(0, 0, 0) translateY(0);
          transform: translate3d(0, 0, 0) translateY(0);
  -webkit-transition: opacity 1s ease, -webkit-transform 1s ease 0.25s;
  transition: opacity 1s ease, -webkit-transform 1s ease 0.25s;
  transition: opacity 1s ease, transform 1s ease 0.25s;
  transition: opacity 1s ease, transform 1s ease 0.25s, -webkit-transform 1s ease 0.25s;
}
.tl-item:hover .tl-content {
	opacity: 1;
	-webkit-transform: translateY(0);
	transform: translateY(0);
	-webkit-transition: all 0.75s ease 0.5s;
	transition: all 0.75s ease 0.5s;
	text-align: left;
}
.tl-item:hover .tl-bg {
  -webkit-filter: grayscale(0);
          filter: grayscale(0);
}

.tl-content {
  -webkit-transform: translate3d(0, 0, 0) translateY(25px);
          transform: translate3d(0, 0, 0) translateY(25px);
  position: relative;
  z-index: 1;
  text-align: center;
  margin: 0 1.618em;
  top: 20%;
  opacity: 0;
}
.tl-content h1 {
	font-family: Verdana;
	text-transform: uppercase;
	color: LemonChiffon;
	font-size: 24px;
	font-weight: bold;
	line-height: normal;
}

.tl-year {
  position: absolute;
  top: 10%;
  left: 50%;
  -webkit-transform: translateX(-50%) translateY(-50%);
          transform: translateX(-50%) translateY(-50%);
  z-index: 1;
  border-top: 1px solid LemonChiffon;
  border-bottom: 1px solid LemonChiffon;
}
.tl-year p {
  font-family: Verdana;
  font-size: 12px;
  line-height: 0;
}

.tl-bg {
  -webkit-transform: translate3d(0, 0, 0);
          transform: translate3d(0, 0, 0);
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  background-size: cover;
  background-position: center center;
  -webkit-transition: -webkit-filter 0.5s ease;
  transition: -webkit-filter 0.5s ease;
  transition: filter 0.5s ease;
  transition: filter 0.5s ease, -webkit-filter 0.5s ease;
  -webkit-filter: grayscale(100%);
          filter: grayscale(100%);
}