body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: #3c76af;
    user-select: none;
}

.container {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 30px;
    /* background: linear-gradient(
        325deg, 
        #03001e 0%, 
        #7303c0 30%,
        #ec38bc 70%, 
        #fdeff9 100%
    ); */
    background: radial-gradient(circle, #c4c9dd 0%, #292285 82%);
    padding: 40px 60px;
}

h2 {
    font-size: 3em;
    color: #0c1bf0;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    text-shadow: 2px 2px #000;
}

.reset {
    padding: 15px 20px 10px;
    width: 100%;
    color: #000;
    background-color: #3c76af;
    border: 1px solid;
    border-radius: 10px;
    font-size: 1.5em;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    cursor: pointer;
    font-weight: 600;
}

.reset:focus {
    color: #fff;
    background-color: #000;
}

.game {
    width: 430px;
    height: 430px;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    transform-style: preserve-3d;
    perspective: 500px;
}

.item {
    position: relative;
    width: 100px;
    height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #b0e2ee;
    font-size: 3em;
    transform: rotateY(180deg);
    transition: 0,25s;
    border: 5px solid #180d47;
    border-radius: 5px;
}

.item::after {
    content: "";
    position: absolute;
    inset: 0;
    background-color: #6ac7ec;
    transition: 0.25s;
    transform: rotateY(0deg);
    backface-visibility: hidden;
    /* opacity: 0.85; */
}

.item.boxOpen {
    transform: rotateY(0deg);
}

.boxOpen::after,
.boxMath::after {
    transform: rotateY(180deg);
}

footer {
    margin-top: 20px;
    padding: 10px;
    text-align: center;
    color: white;
}