#timeline {

(max-width: 470px)

display:none;

(min-width: 470px) and (max-width: 980px)

display:none;

(min-width: 980px)

display: -webkit-box;
display: flex;
background-color: rgba(0,0,0,0.5);;
}

#timeline:hover .tl-item {
width: 33.33%;
}

.tl-item {
-webkit-transform: translate3d(0, 0, 0);
transform: translate3d(0, 0, 0);
position: relative;
width: 33.33%;
height: 100vh;
max-height: 500px;
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(0,0,0, 0.20);
opacity: 1;
-webkit-transition: opacity 0.5s ease;
transition: opacity 0.5s ease;
}

.tl-item:before {
background: -webkit-gradient(linear, left top, left bottom, from(rgba(0, 0, 0, 0)), color-stop(75%, black));
background: linear-gradient(to bottom, rgba(0, 0, 0, 0) 0%, black 75%);
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: 38% !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;
}

.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: 55%;
opacity: 0;
}

.tl-content h1 {
text-transform: uppercase;
color: #1779cf;
font-size: 1.44rem;
font-weight: normal;
}

.tl-year {
position: absolute;
top: 50%;
left: 50%;
-webkit-transform: translateX(-50%) translateY(-50%);
transform: translateX(-50%) translateY(-50%);
z-index: 1;
}

.tl-year p {
font-size: 25px;
line-height: 1;
background: rgb(0 177 238);
padding: 20px 24px;
}

.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;
}