* {
    box-sizing: border-box;
}

body {
    display: flex;
    height: 100vh;
    align-items: center;
    flex-direction: column;
    justify-content: center;
    margin: 0;
    background-size: cover;
    font-family: 'Exo 2', sans-serif;
}

.fullscreen-bg__video {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    overflow: hidden;
    z-index: -100;
    opacity: 0.90;
    width: 100%;
    height: 100%
}

.fullscreen-bg {
    position: absolute;
    /* top: 0;
left: 0; */
    width: 100%;
    height: 100%;
    /* color: thistle; */
    left: 0px;
    top: 0px;
    z-index: -1;
}

header {
    font-size: 3vw;
    justify-content: start;
    /* font-size: 40px; */
    align-content: center;
    letter-spacing: 10px;
    height: 10%;
    margin-bottom: 40px;
    font-weight: bold;
    color: #fff;
    text-shadow: #fff 0 0 4px, yellow 0 -5px 10px, orange 0 -15px 20px, red 0 -25px 50px;
}

h1 {
    margin: 0;
}

.grid {
    align-content: center;
    height: 420px;
    width: 760px;
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 50px;
    border-bottom: 3px solid #ff4d07;
}

.grid div {
    display: flex;
    /* border: 2px solid rgb(255, 255, 255); */
    flex-grow: 1;
    height: 9%;
    width: 9%;
    margin: 2px;
    background-size: contain;
    background-position: center;
    background-repeat: no-repeat;
}

.activeAlien {
    filter: invert(1);
    background-image: url('images/Space-13-512.png');
}

.spaceship {
    background-image: url('images/black\ and\ white.png');
    filter: invert(1);
    background-size: 117%;
}

.bullet {
    background-image: url('images/missile\ ufo.png');
}

.bomb {
    filter: hue-rotate(90deg);
    background-image: url('images/missile.png');
}

.score,
.lives {
    display: inline-block;
    width: 150px;
    font-size: 20px;
    color: white;
}

.lives {
    float: right;
    text-align: right;
}

.endMessage {
    color: #ffffff;
    font-size: 34px;
    text-align: center;
    margin-top: 20px;
    letter-spacing: 15px;
    font-weight: bold;
}

.endMessage {
    color: #ffffff;
    font-size: 34px;
    text-align: center;
    margin-top: 20px;
    letter-spacing: 15px;
    font-weight: bold;
    animation-name: glowAnim;
    animation-duration: 2s;
    animation-iteration-count: infinite;
}

@keyframes glowAnim {
    from {
        text-shadow: 0px 0px 10px rgba(255, 255, 255, 0), 0px 0px 30px rgba(255, 255, 255, 0.3), 0px 0px 50px rgba(255, 255, 255, 0.6), 0px 0px 180px rgba(255, 255, 255, 0.9);
        color: #fff;
    }
    to {
        text-shadow: 0 0 5px rgba(0, 5px, 5px, 1);
    }
}

.start {
    color: white;
    font-size: 30px;
    text-align: center;
    margin-top: 30px;
    letter-spacing: 10px;
    font-weight: bold;
}

.start:hover {
    cursor: pointer;
    letter-spacing: 12px;
}

.explosion {
    background-image: url('images/DarlingScholarlyDoe-small.gif');
}

.hidden {
    display: none!important;
}

.countdown {
    color: white;
    font-size: 30px;
    text-align: center;
    margin-top: 30px;
    letter-spacing: 10px;
    font-weight: bold;
}

@media (min-aspect-ratio: 16/9) {
    .fullscreen-bg__video {
        width: 100%;
        height: auto;
    }
}

@media (max-aspect-ratio: 16/9) {
    .fullscreen-bg__video {
        width: auto;
        height: 100%;
    }
}