styles.css

body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    text-align: center;
    background: #f0f8ff;
    padding: 60px;
}

#game-board {
    display: grid;
    grid-template-columns: repeat(4, 100px);
    gap: 10px;
    justify-content: center;
    margin: 20px auto;
}

.card {
    background: #fa90e2;
    color: transparent;
    font-size: 2rem;
    width: 100px;
    height: 100px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background 0.3s, transform 0.4s;
}

.card.flipped {
    background: white;
    color: black;
    transform: rotateY(200deg);
}

button {
    cursor: pointer;
}