body {
    font-family: 'Arial', sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: #f0f0f0;
    margin: 0;
}

#game-container {
    text-align: center;
    background-color: #fff;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    width: 90%;
    max-width: 800px;
}

#game-start-area, #game-play-area {
    padding: 10px;
}

#num-players-select, #setup-game-button {
    font-size: 1.1em;
    padding: 8px 15px;
    margin: 10px;
    border-radius: 5px;
    border: 1px solid #ccc;
    cursor: pointer;
}

#setup-game-button {
    background-color: #007bff;
    color: white;
    border: none;
    transition: background-color 0.3s ease;
}

#setup-game-button:hover {
    background-color: #0056b3;
}

#player-info {
    margin-bottom: 15px;
    font-size: 1.2em;
    font-weight: bold;
}

.player-score {
    display: inline-block;
    margin: 0 10px;
    padding: 5px 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    background-color: #e9e9e9;
}

.current-player {
    background-color: #ffeb3b;
    border-color: #ffc107;
}

#game-table {
    display: grid;
    /* 40枚（8x5）に合わせて調整 */
    grid-template-columns: repeat(8, 80px);
    grid-template-rows: repeat(5, 80px);
    gap: 10px;
    margin: 20px auto;
    justify-content: center;
}

.card {
    width: 80px;
    height: 80px;
    position: relative;
    perspective: 1000px;
    cursor: pointer;
    border-radius: 8px;
}

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

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

.card-face {
    width: 100%;
    height: 100%;
    position: absolute;
    backface-visibility: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    font-weight: bold;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.front {
    background-color: #87ceeb;
}

.back {
    background-color: #f8f8f8;
    color: #333;
    transform: rotateY(180deg);
}

.card.skull .back p {
    color: #dc3545;
    font-size: 40px;
}

.message {
    font-size: 2em;
    font-weight: bold;
    color: #007bff;
    min-height: 1.5em;
    margin-bottom: 15px;
}

#start-button {
    background-color: #28a745;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1.2em;
    transition: background-color 0.3s ease;
    margin-top: 15px;
}

#start-button:hover {
    background-color: #218838;
}