/* CRT filter - Alec Lownes (http://aleclownes.com/2017/02/01/crt-display.html) */
    @keyframes flicker {
        0% {
            opacity: 0.27861;
        }

        5% {
            opacity: 0.34769;
        }

        10% {
            opacity: 0.23604;
        }

        15% {
            opacity: 0.90626;
        }

        20% {
            opacity: 0.18128;
        }

        25% {
            opacity: 0.83891;
        }

        30% {
            opacity: 0.65583;
        }

        35% {
            opacity: 0.67807;
        }

        40% {
            opacity: 0.26559;
        }

        45% {
            opacity: 0.84693;
        }

        50% {
            opacity: 0.96019;
        }

        55% {
            opacity: 0.08594;
        }

        60% {
            opacity: 0.20313;
        }

        65% {
            opacity: 0.71988;
        }

        70% {
            opacity: 0.53455;
        }

        75% {
            opacity: 0.37288;
        }

        80% {
            opacity: 0.71428;
        }

        85% {
            opacity: 0.70419;
        }

        90% {
            opacity: 0.7003;
        }

        95% {
            opacity: 0.36108;
        }

        100% {
            opacity: 0.24387;
        }
    }

    .crt::after {
        content: " ";
        display: block;
        position: fixed;
        top: 0;
        left: 0;
        bottom: 0;
        right: 0;
        background: rgba(18, 16, 16, 0.1);
        opacity: 0;
        z-index: 2;
        pointer-events: none;
        animation: flicker 0.15s infinite;
    }

    .crt::before {
        content: " ";
        display: block;
        position: fixed;
        top: 0;
        left: 0;
        bottom: 0;
        right: 0;
        background: linear-gradient(rgba(18, 16, 16, 0) 50%, rgba(0, 0, 0, 0.25) 50%), linear-gradient(90deg, rgba(255, 0, 0, 0.06), rgba(0, 255, 0, 0.02), rgba(0, 0, 255, 0.06));
        z-index: 2;
        background-size: 100% 2px, 3px 100%;
        pointer-events: none;
    }

    .crt {
        position: absolute;
        top: 0;
        left: 0;
        bottom: 0;
        right: 0;
        cursor: url("red.cur"), crosshair;
    }