body {
    font-family: 'Noto Serif JP', serif;
    background-color: #0a5c36;
    color: #ffffff;
    margin: 0;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 100vh;
}

.game-area {
    background-color: #0d8049;
    border-radius: 10px;
    padding: 20px;
    margin-top: 20px;
    box-shadow: 0 0 10px rgba(0,0,0,0.5);
    width: 100%;
    max-width: 800px;
}

.hand {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 20px;
}

.card img {
    max-width: 100%;
    border-radius: 5px;
    box-shadow: 2px 2px 5px rgba(0,0,0,0.3);
}

.controls {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 20px;
}

button {
    background-color: #ffd700;
    color: #000000;
    border: none;
    padding: 10px 20px;
    font-size: 16px;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #ffec8b;
}

.rules {
    background-color: rgba(0,0,0,0.8);
    color: #ffffff;
    padding: 20px;
    border-radius: 10px;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    max-width: 80%;
    max-height: 80%;
    overflow-y: auto;
    display: none;
}

.close-rules {
    position: absolute;
    top: 10px;
    right: 10px;
    background: none;
    border: none;
    color: #ffffff;
    font-size: 20px;
    cursor: pointer;
}

.message {
    font-size: 24px;
    font-weight: bold;
    text-align: center;
    margin-top: 20px;
    padding: 10px;
    background-color: rgba(255,255,255,0.1);
    border-radius: 10px;
}

/* デバイス対応のスタイル */
@media (max-width: 600px) {
    .card img {
        width: 70px;
        height: 98px;
    }

    .message {
        font-size: 18px;
    }
}