body {
    font-family: 'Arial', sans-serif;
    background-color: #f0f8ff;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    flex-direction: column;
    text-align: center;
}

#game-container {
    position: relative;
    width: 400px;
    height: 600px; /* ゲームエリアの高さ変更 */
    background-color: white;
    padding: 10px;
    border-radius: 15px;
    box-shadow: 0px 10px 20px rgba(0, 0, 0, 0.1);
}

#task-container {
    margin-bottom: 10px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 20px;
}

#task-container img {
    height: 40px; /* お題画像の高さ変更 */
    object-fit: contain;
}

#score-container, #timer-container {
    font-size: 20px;
    margin: 10px;
    display: inline-block;
}

#grid-container {
    display: grid;
    grid-template-columns: repeat(5, 1fr); /* 5列 */
    grid-gap: 2px; /* 画像間の隙間 */
    justify-items: center;
    margin-top: 30px;
}

#grid-container img {
    height: 40px; /* 画像セットの高さ変更 */
    object-fit: contain;
    cursor: pointer;
    transition: transform 0.3s ease, opacity 0.3s ease;
}

.selected {
    opacity: 0.5;
    border: 2px solid #2ecc71;
}

.wrong {
    animation: shake 0.5s ease-in-out;
}

@keyframes shake {
    0% { transform: rotate(0deg); }
    25% { transform: rotate(15deg); }
    50% { transform: rotate(0deg); }
    75% { transform: rotate(-15deg); }
    100% { transform: rotate(0deg); }
}

button {
    font-size: 18px;
    padding: 10px 20px;
    background-color: #f39c12;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    margin-top: 10px;
}

button:hover {
    background-color: #e67e22;
}

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