custom.css

.timeline__item__icon-wrap:before {
    content: " ";
    display: block;
    border-left: 4px dotted #47a0ff;
    height: 100%;
    position: absolute;
    top: 0;
    left: 50%;
    -moz-transform: translate(-50%,0);
    -ms-transform: translate(-50%,0);
    -webkit-transform: translate(-50%,0);
    -o-transform: translate(-50%,0);
    transform: translate(-50%,0);
    z-index: 1;
}