body {
    font-family: Arial, sans-serif;
    background-color: #f0f0f0;
    margin: 0;
    padding: 0;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: #ffffff;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    border-radius: 5px;
}

h1 {
    text-align: center;
    color: #333;
}

.instructions {
    text-align: center;
    color: #666;
    margin-bottom: 20px;
}

#game-area {
    text-align: center;
    margin-bottom: 20px;
}

#flag-image {
    height: 200px; /* 固定高度 */
    width: auto; /* 宽度自动调整 */
    max-width: 100%; /* 确保图片不会超出容器宽度 */
    object-fit: contain; /* 保持图片比例，确保完整显示 */
    border: 1px solid #ddd;
    margin-bottom: 20px;
}

#options-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
}

.option-button {
    padding: 10px 20px;
    font-size: 16px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s;
    width: 80%;
    max-width: 300px;
}

.option-button:hover {
    background-color: #45a049;
}

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

#flag-count, #start-game {
    padding: 10px;
    font-size: 16px;
}

#start-game {
    background-color: #008CBA;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s;
}

#start-game:hover {
    background-color: #007B9A;
}

#score, #feedback {
    text-align: center;
    font-size: 18px;
    margin-top: 20px;
}

#feedback {
    font-weight: bold;
    color: #4CAF50;
}

#answer-history {
    margin-top: 30px;
    text-align: center;
}

#history-list {
    list-style-type: none;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
}

.history-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    border: 1px solid #ddd;
    padding: 10px;
    border-radius: 5px;
    width: 100px;
}

.history-item img {
    width: 60px;
    height: 40px;
    object-fit: contain;
    margin-bottom: 5px;
}

.history-item .country-name {
    font-size: 12px;
    text-align: center;
}

.history-item.correct {
    background-color: #e8f5e9;
}

.history-item.incorrect {
    background-color: #ffebee;
}