body {
    background: #262626;
    overflow: hidden;
}

ul {
    display: flex;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    -webkit-transform: translate(-50%, -50%);
    -moz-transform: translate(-50%, -50%);
    -ms-transform: translate(-50%, -50%);
    -o-transform: translate(-50%, -50%);
}

ul li {
    list-style: none;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 8vh;
    letter-spacing: 1.5vw;
    color: #484848;
    text-shadow: none;
    animation: animate 1s infinite linear;
    -webkit-animation: animate 1s infinite linear;
}

@keyframes animate{
    0%{
        color: #484848;
        text-shadow: none;        
    }
    18% {
        color: #484848;
        text-shadow: none;
    }
    20% {
        color: skyblue;
        text-shadow: 0 0 7px skyblue, 0 0 20px blue;
    }
    30% {
        color: #484848;
        text-shadow: none;
    }
    35% {
        color: skyblue;
        text-shadow: 0 0 7px skyblue, 0 0 20px blue;
    }
    70% {
        color: #484848;
        text-shadow: none;
    }
    85% {
        color: skyblue;
        text-shadow: 0 0 7px skyblue, 0 0 20px blue;
    }
    90% {
        color: #484848;
        text-shadow: none;
    }
    100% {
        color: #484848;
        text-shadow: none;
    }
}

ul li:nth-child(1){
    animation-delay: .2s;
}
ul li:nth-child(2) {
    animation-delay: .4s;
}
ul li:nth-child(3) {
    animation-delay: .6s;
}
ul li:nth-child(4) {
    animation-delay: .8s;
}
ul li:nth-child(5) {
    animation-delay: 1s;
}
ul li:nth-child(6) {
    animation-delay: 1.2s;
}
ul li:nth-child(7) {
    animation-delay: 1.4s;
}
ul li:nth-child(8) {
    animation-delay: 1.6s;
}
ul li:nth-child(9) {
    animation-delay: 1.8s;
}
ul li:nth-child(10) {
    animation-delay: 2s;
}
ul li:nth-child(11) {
    animation-delay: 2.2s;
}
ul li:nth-child(12) {
    animation-delay: 2.4s;
}