*,
*::before,
*::after {
    box-sizing: border-box;
}
* {
    margin: 0;
}
body {
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}
img,
picture,
video,
canvas,
svg {
    display: block;
    max-width: 100%;
}
input,
button,
textarea,
select {
    font: inherit;
}
p,
h1,
h2,
h3,
h4,
h5,
h6 {
    overflow-wrap: break-word;
}

.libre-baskerville-regular {
    font-family: "Libre Baskerville", serif;
    font-weight: 400;
    font-style: normal;
}

.libre-baskerville-bold {
    font-family: "Libre Baskerville", serif;
    font-weight: 700;
    font-style: normal;
}

.libre-baskerville-regular-italic {
    font-family: "Libre Baskerville", serif;
    font-weight: 400;
    font-style: italic;
}

body {
    background-color: #b0ba50;

    font-family: "Libre Baskerville", serif;
    font-weight: 400;
    font-style: normal;
    color: white;

    --card-soft-green: hsl(67.7, 43%, 60.8%);
    --card-soft-green-hover: hsl(67.7, 43%, 70.8%);
    --card-medium-green: hsl(123.9, 24.3%, 50.8%);
    --card-medium-green-hover: hsl(123.9, 24.3%, 60.8%);
    --card-dark-green: hsl(117.8, 33.8%, 31.4%);
    --card-dark-green-hover: hsl(117.8, 33.8%, 41.4%);
    --card-red: hsl(4.1, 79.2%, 52.9%);
    --card-red-hover: hsl(4.1, 79.2%, 62.9%);
}

.sg {
    background-color: var(--card-soft-green);
    &:hover {
        background-color: var(--card-soft-green-hover);
    }
}

.mg {
    background-color: var(--card-medium-green);
    &:hover {
        background-color: var(--card-medium-green-hover);
    }
}

.dg {
    background-color: var(--card-dark-green);
    &:hover {
        background-color: var(--card-dark-green-hover);
    }
}

.r {
    background-color: var(--card-red);
    &:hover {
        background-color: var(--card-red-hover);
    }
}

.aspect-1 {
    aspect-ratio: 1.4 / 1;
}

.aspect-2 {
    aspect-ratio: 1 / 1.3;
}

.aspect-3 {
    aspect-ratio: 1 / 1.6;
}

.aspect-4 {
    aspect-ratio: 1.8 / 1;
}

.grid {
    margin: 3em auto;
    max-width: 480px;
    width: 90%;
    display: flex;
    flex-direction: column;
    gap: 5em;
}

.flip {
    background-color: transparent;
    width: 100%;
    perspective: 1000px;
}

.flip-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform 0.8s;
    transform-style: preserve-3d;
}

.flip.flipped .flip-inner {
    transform: rotateY(180deg);
}

.flap-back {
    width: 100%;
    height: 100%;
    position: absolute;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
    background-color: orange;
    transform: rotateY(180deg);
    display: flex;
    flex-direction: column;
    justify-content: center;

    & div {
        position: absolute;
        top: 0;
        left: 0;
        display: grid;
        width: 100%;
        height: 100%;
        align-items: center;
        justify-items: center;
        text-align: center;
    }
}

.flap-front span {
    display: block;
    text-align: center;
}

.flap {
    display: grid;
    width: 100%;
    height: 100%;
    transition: background-color 0.3s ease-in-out;
    justify-items: center;
    align-items: center;
    position: absolute;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;

    & span {
        font-size: 3em;
    }
}

.flap::before {
    content: "";
    background-color: white;
    position: absolute;
    top: -2em;
    left: -1em;
    bottom: -2em;
    right: -1em;
    z-index: -1;

    --mask: radial-gradient(5px at 25% 0, #0000 98%, #000) 50% 5px/20px 51%
            repeat-x,
        radial-gradient(5px at 75% 50%, #000 99%, #0000 101%) top/20px 10px
            repeat-x,
        radial-gradient(5px at 75% 100%, #0000 98%, #000) calc(50% + 10px)
            calc(100% - 5px) / 20px 51% repeat-x,
        radial-gradient(5px at 25% 50%, #000 99%, #0000 101%) calc(50% + 10px)
            100%/20px 10px repeat-x;
    -webkit-mask: var(--mask);
    mask: var(--mask);
}

.flap::after {
    content: "";
    background-color: white;
    position: absolute;
    top: -1em;
    left: -2em;
    bottom: -1em;
    right: -2em;
    z-index: -1;

    --mask: radial-gradient(5px at 0 75%, #0000 98%, #000) 5px 50%/51% 20px
            repeat-y,
        radial-gradient(5px at 50% 25%, #000 99%, #0000 101%) left/10px 20px
            repeat-y,
        radial-gradient(5px at 100% 25%, #0000 98%, #000) calc(100% - 5px)
            calc(50% + 10px) / 51% 20px repeat-y,
        radial-gradient(5px at 50% 75%, #000 99%, #0000 101%) 100%
            calc(50% + 10px) / 10px 20px repeat-y;
    -webkit-mask: var(--mask);
    mask: var(--mask);
}

#snow-container {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 1;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
}

@keyframes fall {
    0% {
        opacity: 0;
    }

    50% {
        opacity: 1;
    }

    100% {
        top: 100vh;

        opacity: 1;
    }
}

@keyframes sway {
    0% {
        margin-left: 0;
    }
    25% {
        margin-left: 50px;
    }
    50% {
        margin-left: -50px;
    }
    75% {
        margin-left: 50px;
    }
    100% {
        margin-left: 0;
    }
}

@keyframes spin {
    100% {
        transform: rotate(240deg);
    }
}

.snow {
    animation:
        fall ease-in infinite,
        sway ease-in-out infinite,
        spin linear infinite;
    color: white;
    position: absolute;
    top: -50%;
    left: -50%;
}