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

.container {
    background: white;
    padding: 10px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
    width: 100%;
    max-width: 600px;
    box-sizing: border-box;
    display: flex;
    flex-direction: column;
    justify-content: center;
    height: 100vh;
    overflow: auto;
}

h1 {
    text-align: center;
    margin-bottom: 10px;
}

.question-section, .image-section, .choices-section, .input-section {
    margin-bottom: 10px;
}

.question-section {
    background: #e0f7fa;
    padding: 10px;
    border-radius: 5px;
    text-align: center;
}

.ps-text {
    font-style: italic; /* 斜体 */
    font-size: 14px; /* 字体变小 */
    color: grey; /* 字体变灰 */
    text-align: left; /* 左对齐 */
}

.image-section img {
    max-width: 100%;
    border-radius: 5px;
}

.choices-section button {
    display: block;
    width: 100%;
    margin-bottom: 10px;
    padding: 10px;
    background-color: #007BFF;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

.choices-section button:last-child {
    margin-bottom: 0;
}

.input-section {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.input-section label {
    display: flex;
    align-items: center;
    gap: 10px;
}

.input-section input {
    flex: 1;
    padding: 10px;
    font-size: 16px;
    border: 1px solid #ccc;
    border-radius: 5px;
    box-sizing: border-box;
}

.result-section {
    margin-top: 10px; /* 确保有间距 */
    font-weight: bold; /* 加粗文本 */
    color: red; /* 结果颜色 */
}

.action-button {
    display: block;
    width: 100%;
    margin: 10px 0;
    padding: 10px;
    background-color: #28a745;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    align-self: center;
}

.navigation-buttons {
    display: flex;
    justify-content: space-between;
    margin-top: 10px;
}

.nav-button {
    flex: 1;
    margin: 0 5px;
    padding: 10px;
    background-color: #6c757d;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

.nav-button:first-child {
    margin-left: 0;
}

.nav-button:last-child {
    margin-right: 0;
}

button:disabled {
    background-color: #7ba1ff;
    cursor: not-allowed;
}

@media (max-width: 600px) {
    .container {
        padding: 10px;
    }

    .action-button, .nav-button {
        padding: 10px;
    }
}