body {
    margin: 0;
    background: #000;
    color: #fff;
}

.matrix {
    width: 50em;
    margin: 0 auto;
}

p {
    font-size: 1.3em;
    text-orientation: upright;
    writing-mode: vertical-rl;
    display: inline-block
}

p span {
    animation: matrix 1.5s linear infinite;
    opacity: 0;
}

@keyframes matrix {
    0% {
        color: #fff;
        opacity: 1;
    }

    5% {
        color: #2bc235;
        opacity: 1;
    }

    100% {
        opacity: 0;
    }
}