body {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    margin: 0;
    background-color: black;
    color: white;
    font-family: Arial, sans-serif;
}

h1 {
    margin-bottom: 20px;
}

.game-board {
    display: grid;
    grid-template-columns: repeat(4, 100px);
    grid-gap: 10px;
    margin-bottom: 20px;
}

.card {
    width: 100px;
    height: 100px;
    perspective: 1000px;
    cursor: pointer;
}

.card-inner {
    width: 100%;
    height: 100%;
    transition: transform 0.6s;
    transform-style: preserve-3d;
    position: relative;
}

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

.card-front, .card-back {
    width: 100%;
    height: 100%;
    position: absolute;
    backface-visibility: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    border-radius: 8px;
}

.card-front {
    background-color: #3498db;
}

.card-back {
    background-color: #ecf0f1;
    transform: rotateY(180deg);
}

#reset-button {
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
    border: none;
    border-radius: 5px;
    background-color: #e74c3c;
    color: white;
}

footer {
    margin-top: 30px;
    font-size: 14px;
    height: 50px;
    width: 50%;
    border: 1px solid black;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 100px;
    text-decoration: none;
    box-shadow: 0 0 5px rgba(0, 0, 0, .6);
    border: none;
    background-color: #9EBAF3;
    color: FFFFFF;
    font-weight: bold;
}