body {
    font-family: 'Poppins', sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.container {
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    text-align: center;
    max-width: 800px;
    width: 90%;
}

h1 {
    color: #4a5568;
    margin-bottom: 2rem;
}

.game-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.info-card {
    background-color: #f7fafc;
    border-radius: 10px;
    padding: 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.info-card .icon {
    font-size: 1.5rem;
}

.info-card p {
    margin: 0;
    font-size: 0.8rem;
    color: #718096;
}

.info-card span:not(.icon) {
    font-weight: 600;
    color: #4a5568;
}

#game-board {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(80px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.card {
    aspect-ratio: 1;
    background-color: #4a5568;
    border-radius: 10px;
    cursor: pointer;
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

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

.card-front, .card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 10px;
    font-size: 2rem;
}

.card-front {
    background-color: #4a5568;
}

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

#start-button {
    background-color: #4299e1;
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 9999px;
    cursor: pointer;
    transition: background-color 0.3s;
}

#start-button:hover {
    background-color: #3182ce;
}

#start-button:disabled {
    background-color: #cbd5e0;
    cursor: not-allowed;
}