/* Reset */
*,
*::after,
*::before {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 62.5%;
}

@media (max-width: 75em) {
    html {
        font-size: 56.25%;
    }
}

@media (max-width: 56.25em) {
    html {
        font-size: 50%;
    }
}

@media (min-width: 112.5em) {
    html {
        font-size: 75%;
    }
}

body {
    height: 100vh;
    
}

.artboard {
    display: flex;
    flex-flow: row;
    align-items: center;
    justify-content: center;
    
    height: 100%;
    position: relative;
}

@media (max-width: 37.5em) {
    .artboard {
        padding: 1rem;
    }
}

.card {
    flex: initial;
    position: relative;
    height: 52rem;
    width: 48rem;
    -moz-perspective: 200rem;
    perspective: 200rem;
    margin: 2rem;
}

.card__side {
    height: 52rem;
    transition: all 0.8s ease;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    -webkit-backface-visibility: hidden;
    /* We don't want to see the back part of the element. */
    backface-visibility: hidden;
    /* We don't want to see the back part of the element. */
    border-radius: 3px;
    overflow: hidden;
    /* The image is overflowing the parent. */
    box-shadow: 0 2rem 6rem rgba(0, 0, 0, 0.15);
}

.card__side--front {
    background-image: linear-gradient(to right bottom, rgba(30, 11, 54, 0.65), rgba(202, 55, 130, 0.7)), url(https://cdn.spacetelescope.org/archives/images/screen/heic0406a.jpg);
}

.card__side--back {
    background-color: #fff;
    transform: rotateY(180deg);
}

.card:hover .card__side--back {
    transform: rotateY(0);
}

.card:hover .card__side--front {
    transform: rotateY(-180deg);
}

.card__theme {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    top: 54%;
    width: 90%;
    text-align: center;
}

.card__theme-box {
    color: #fff;
    margin-bottom: 8rem;
}

.card__subject {
    font-family: "Inconsolata", monospace;
    letter-spacing: 0.8rem;
    font-size: 1.6rem;
    text-transform: uppercase;
    margin-bottom: 1rem;
}

.card__title {
    font-family: "VT323", monospace;
    text-transform: uppercase;
    font-size: 6rem;
    font-weight: 100;
}

.card__cover {
    position: relative;
    background-size: cover;
    height: 14rem;
    -webkit-clip-path: polygon(0 0, 100% 0, 100% 85%, 0 100%);
    clip-path: polygon(0 0, 100% 0, 100% 85%, 0 100%);
    border-top-left-radius: 3px;
    border-top-right-radius: 3px;
    background-image: linear-gradient(to top right, rgba(30, 11, 54, 0.65), rgba(202, 55, 130, 0.65)), url(https://cdn.spacetelescope.org/archives/images/screen/heic0406a.jpg);
}

.card__heading {
    text-align: center;
    color: #fff;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 75%;
}

.card__heading-span {
    font-family: "VT323", monospace;
    font-size: 4.2rem;
    font-weight: 300;
    text-transform: uppercase;
    padding: 1rem 1.5rem;
    color: #fff;
}

.card__details {
    font-family: "Inconsolata", monospace;
    padding: 4rem 2rem;
}

.card__details ul {
    list-style: none;
    width: 80%;
    margin: 0 auto;
}

.card__details ul li {
    text-align: center;
    font-size: 1.8rem;
    padding: 1rem;
}

.card__details ul li:not(:last-child) {
    border-bottom: 1px solid #eee;
}

@media only screen and (max-width: 37.5em),
only screen and (hover: none) {
    .card {
        height: auto;
        border-radius: 3px;
        background-color: #fff;
        box-shadow: 0 2rem 6rem rgba(0, 0, 0, 0.15);
    }

    .card__side {
        height: auto;
        position: relative;
        box-shadow: none;
    }

    .card__side--front {
        clip-path: polygon(0 15%, 100% 0, 100% 100%, 0 100%);
    }

    .card__side--back {
        transform: rotateY(0);
    }

    .card:hover .card__side--front {
        transform: rotateY(0);
    }

    .card__details {
        padding: 3rem 2rem;
    }

    .card__theme {
        position: relative;
        top: 0;
        left: 0;
        transform: translate(0);
        width: 100%;
        padding: 5rem 4rem 1.5rem 4rem;
        text-align: right;
    }

    .card__theme-box {
        margin-bottom: 1.5rem;
    }

    .card__title {
        font-size: 4rem;
    }
}