@charset "UTF-8";
:root {
    --primary-color: #4CAF50;
    --secondary-color: #2196F3;
    --background-color: #f0f2f5;
    --text-color: #333;
    --border-color: #ddd;
    --card-shadow: 0 2px 8px rgba(0,0,0,0.08);
    --hover-shadow: 0 4px 12px rgba(0,0,0,0.12);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 90%;
    width: 90%;
    margin: 0 auto;
    padding: 12px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

/* 题目类型选择区域 */
.question-types-container {
    background: white;
    padding: 12px;
    border-radius: 12px;
    box-shadow: var(--card-shadow);
    width: 100%;
}

.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--background-color);
}

.section-title {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-color);
    margin: 0;
    padding: 0;
    display: flex;
    align-items: center;
    gap: 8px;
}

.type-controls {
    display: flex;
    gap: 8px;
    margin: 0;
}

.type-controls button {
    padding: 6px 12px;
    border: 1px solid var(--border-color);
    background: white;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 14px;
    color: var(--text-color);
}

.type-controls button:hover {
    background: var(--background-color);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.question-types {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 16px;
    width: 100%;
}

.type-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    background: var(--background-color);
    border-radius: 8px;
    transition: all 0.3s ease;
}

.type-item:hover {
    background: #e8f5e9;
}

.type-item input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
    margin: 0;
    padding: 0;
    flex-shrink: 0;
    accent-color: #1976D2;
}

.type-item label {
    font-size: 15px;
    color: var(--text-color);
    cursor: pointer;
}

/* 每页题目数设置区域 */
.questions-per-page-container {
    background: white;
    padding: 24px;
    border-radius: 12px;
    box-shadow: var(--card-shadow);
    width: 100%;
}

.questions-per-page {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    width: 100%;
    margin-top: 16px;
}

.questions-per-page button {
    padding: 8px 16px;
    border: 1px solid var(--border-color);
    background: white;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 14px;
    color: var(--text-color);
}

.questions-per-page button:hover {
    background: var(--background-color);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.questions-per-page button.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* 题目展示区域 */
.questions-container {
    background: white;
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--card-shadow);
    display: grid;
    gap: 8px; /* 减小卡片间距从16px到8px */
    justify-content: center;
    align-items: center;
    height: 80vh;
    width: 100%;
    position: relative;
    margin: 0;
    box-sizing: border-box;
}

/* 初始状态提示 */
.questions-container:empty::before {
    content: '请选择题目类型并点击"出题"按钮开始练习';
    font-size: 28px;
    color: #666;
    text-align: center;
    padding: 40px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    width: 100%;
    background: linear-gradient(135deg, #f5f7fa 0%, #e4e8eb 100%);
    border: 2px dashed #ccc;
    border-radius: 12px;
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    margin: 0;
    box-sizing: border-box;
}

.questions-container:empty::after {
    content: '快捷键：A - 出题 | S或↓或PgDn - 显示一个答案 | D或↑或PgUp - 显示所有答案 | G - 点名 | Ctrl+K - 重置点名 | Ctrl+Delete - 清除名单';
    font-size: 14px;
    color: #999;
    position: absolute;
    bottom: 24px;
    left: 0;
    right: 0;
    text-align: center;
    white-space: normal;
    z-index: 1;
    padding: 0 20px;
    line-height: 1.4;
}

/* 网格布局配置 */
.questions-container[data-layout="1"] {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr;
    padding: 32px;
}

.questions-container[data-layout="2"] {
    grid-template-columns: repeat(2, 1fr);
    grid-template-rows: 1fr;
    padding: 24px;
}

.questions-container[data-layout="4"] {
    grid-template-columns: repeat(2, 1fr);
    grid-template-rows: repeat(2, 1fr);
    padding: 16px;
}

.questions-container[data-layout="9"] {
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: repeat(3, 1fr);
    padding: 16px;
}

.questions-container[data-layout="16"] {
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(4, 1fr);
    padding: 12px;
}

.questions-container[data-layout="25"] {
    grid-template-columns: repeat(5, 1fr);
    grid-template-rows: repeat(5, 1fr);
    padding: 12px;
}



.question-item {
    background: var(--background-color);
    padding: 2px;
    border-radius: 12px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    position: relative;
    overflow: hidden;
}

.question-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--hover-shadow);
    background: white;
}

.question-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    padding: 4px;
    overflow: hidden;
    position: relative;
}

.question-content {
    display: flex;
    align-items: center;
    justify-content: center;
    white-space: nowrap;
    width: 100%;
    height: 100%;
    padding: 4px;
}

.question-text {
    font-weight: bold;
    color: var(--text-color);
    letter-spacing: 0.5px;
    white-space: nowrap;
    font-size: 24px;
}

.answer {
    color: #000000;
    display: none;
    font-weight: bold;
    letter-spacing: 0.5px;
    white-space: nowrap;
    margin-left: 8px;
    font-size: 30px;
}

/* 字体大小由equationFontResize.js动态设置 */

/* 响应式布局调整 */
@media (max-width: 768px) {
    .container {
        padding: 16px;
        width: 95%;
        max-width: 95%;
        /* 为固定在底部的按钮留出空间 */
        padding-bottom: 80px;
    }

    .questions-container {
        height: auto;
        padding: 0;
        gap: 6px; /* 移动端减小间距从12px到6px */
        display: flex;
        flex-direction: column;
    }

    .question-item {
        width: 100%;
        height: 120px; /* 增加高度从112px到120px */
        margin-bottom: 4px; /* 减少底部间距从8px到4px */
        padding: 2px;
        overflow: hidden;
    }

    .question-wrapper {
        width: 100%;
        height: 100%;
        display: flex;
        align-items: center;
        justify-content: center;
    }

    .question-content {
        display: flex;
        align-items: center;
        justify-content: center;
        height: 100%;
        padding: 2px;
        width: auto !important; /* 强制覆盖任何其他 width 设置 */
    }

    .question-text {
        font-size: 18px;
        line-height: 1.2;
        white-space: nowrap;
        overflow: visible;
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: normal;
    }

    .answer {
        font-size: 18px;
        line-height: 1.2;
        white-space: nowrap;
        overflow: visible;
        margin-left: 8px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: normal;
    }

    /* 移动端分数显示调整 */
    .fraction {
        transform-origin: center;
        transform: none;
        transition: none;
        vertical-align: middle;
        display: inline-flex;
        flex-direction: column;
        align-items: center;
        margin: 0 2px;
        line-height: 1;
    }

    .fraction-line {
        width: 100%;
        height: 1px;
        background-color: var(--text-color);
        margin: 1px 0;
    }

    .fraction-numerator,
    .fraction-denominator {
        line-height: 1;
    }

    /* 确保所有元素大小一致 */
    .question-text .operator,
    .question-text .equals,
    .question-text .number,
    .answer .operator,
    .answer .equals,
    .answer .number {
        vertical-align: middle;
        line-height: 1;
        font-weight: normal;
    }

    /* 调整分数在题目中的对齐方式 */
    .question-text .fraction,
    .answer .fraction {
        vertical-align: middle;
        margin: 0 2px;
        display: inline-flex;
        flex-direction: column;
        align-items: center;
    }

    /* 确保所有布局下的字体大小一致 */
    /* 题目字体大小由equationFontResize.js动态设置 */

    /* 答案字体大小由equationFontResize.js动态设置 */

    /* 调整题目容器高度，为内容留出空间 
    .questions-container[data-layout="1"] .question-item,
    .questions-container[data-layout="2"] .question-item,
    .questions-container[data-layout="4"] .question-item,
    .questions-container[data-layout="9"] .question-item,
    .questions-container[data-layout="16"] .question-item,
    .questions-container[data-layout="25"] .question-item {
        height: 150px; 
        padding: 2px;
    }
        */

    /* 移动端按钮布局调整 */
    .button-container {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        background: white;
        padding: 12px 16px;
        gap: 8px;
        z-index: 1000;
        box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
        display: flex;
        justify-content: center;
        align-items: center;
        width: 100vw;
        box-sizing: border-box;
        margin: 0;
        height: 64px;
    }

    .button-container .btn {
        padding: 8px 12px;
        font-size: 12px;
        min-width: 0 !important;
        flex: 1;
        letter-spacing: 0;
        margin: 0 4px;
        max-width: 140px;
        height: 40px;
        line-height: 24px;
    }

    /* 为底部按钮留出空间 */
    .container {
        padding-bottom: 64px;
        width: 100%;
        max-width: 100%;
    }

    /* 调整题目容器，避免被底部按钮遮挡 */
    .questions-container {
        margin-bottom: 16px;
        width: 100%;
    }

    /* 调整页脚，避免被底部按钮遮挡 */
    .footer {
        margin-bottom: 64px;
        width: 100%;
    }

    /* 移动端全选和取消全选按钮调整 */
    .type-controls {
        display: flex;
        gap: 8px;
        flex-wrap: nowrap;
        overflow-x: auto;
        padding-bottom: 8px;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        -ms-overflow-style: none;
        width: 100%;
        justify-content: flex-end;
    }

    .type-controls::-webkit-scrollbar {
        display: none;
    }

    .type-controls button {
        padding: 6px 8px;
        font-size: 13px;
        white-space: nowrap;
        flex-shrink: 0;
        min-width: auto;
        width: auto;
        margin-top:3px;
    }

    /* 移动端每页题目数显示调整 */
    .questions-per-page {
        display: flex;
        gap: 8px;
        flex-wrap: nowrap;
        overflow-x: auto;
        padding-bottom: 8px;
        margin-top: 12px;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        -ms-overflow-style: none;
    }

    .questions-per-page::-webkit-scrollbar {
        display: none;
    }

    .questions-per-page button {
        padding: 6px 12px;
        font-size: 14px;
        white-space: nowrap;
        flex-shrink: 0;
    }

    .question-types {
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
    }

    .type-item {
        padding: 8px;
    }

    .type-item label {
        font-size: 14px;
    }

    .question-types-title {
        font-size: 16px;
        margin-bottom: 12px;
        padding-bottom: 8px;
    }

    .header h1 {
        font-size: 20px;
    }
    
    .header p {
        font-size: 12px;
    }
    
    .section-title {
        font-size: 18px;
        white-space: nowrap;

        text-overflow: ellipsis;
    }
    
    .questions-per-page-container label {
        font-size: 18px;
    }

    .footer-links {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        grid-row-gap: 0;
        margin-bottom: 16px;
        padding: 0 16px;
    }

    .footer-links a {
        font-size: 14px;
        padding: 2px 0;
        text-align: center;
        color: #666;
        text-decoration: none;
        position: relative;
    }

    .footer-links a:not(:last-child)::after {
        content: '|';
        position: absolute;
        right: -4px;
        color: #999;
    }

    .footer-links a:hover {
        opacity: 0.8;
    }

    .questions-container {
        min-height: 55vh;
        padding: 16px;
        gap: 8px; /* 减小间距从16px到8px */
    }
    
    .questions-container[style*="grid-template-columns: repeat(1, 1fr)"],
    .questions-container[style*="grid-template-columns: repeat(2, 1fr)"] {
        padding: 0;
    }
    
    .questions-container[style*="grid-template-columns: repeat(3, 1fr)"],
    .questions-container[style*="grid-template-columns: repeat(4, 1fr)"] {
        padding: 0;
    }

    /* 移动端初始化提示文字调整 */
    .questions-container:empty::before {
        font-size: 20px;
        padding: 20px;
        line-height: 1.4;
        margin-bottom: 16px;
    }

    .questions-container:empty::after {
        font-size: 14px;
        bottom: auto;
        top: 50%;
        transform: translateY(40px);
        padding: 0 16px;
        white-space: normal;
        text-align: center;
        line-height: 1.4;
    }

    /* 移动端基础字体大小设置 */
    .question-text,
    .answer,
    .question-text .operator,
    .question-text .equals,
    .question-text .number,
    .answer .operator,
    .answer .equals,
    .answer .number,
    .fraction,
    .fraction-numerator,
    .fraction-denominator {
        font-size: 40px;
        line-height: 1;
        font-weight: normal;
        vertical-align: middle;
    }

    /* 移除所有可能影响字体大小的样式 */
    .question-text,
    .answer {
        font-size: 40px;
        line-height: 1.2;
        white-space: nowrap;
        overflow: visible;
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: normal;
    }

    /* 分数显示调整 */
    .fraction {
        display: inline-flex;
        flex-direction: column;
        align-items: center;
        margin: 0 2px;
        font-size: 40px;
    }

    .fraction-line {
        width: 100%;
        height: 1px;
        background-color: var(--text-color);
        margin: 1px 0;
    }

    /* 确保所有布局下的字体大小一致 */
    .questions-container[data-layout="1"] .question-text,
    .questions-container[data-layout="2"] .question-text,
    .questions-container[data-layout="4"] .question-text,
    .questions-container[data-layout="9"] .question-text,
    .questions-container[data-layout="16"] .question-text,
    .questions-container[data-layout="25"] .question-text,
    .questions-container[data-layout="1"] .answer,
    .questions-container[data-layout="2"] .answer,
    .questions-container[data-layout="4"] .answer,
    .questions-container[data-layout="9"] .answer,
    .questions-container[data-layout="16"] .answer,
    .questions-container[data-layout="25"] .answer {
        font-size: 40px;
    }

    /* 调整题目容器高度 */
    .questions-container[data-layout="1"] .question-item,
    .questions-container[data-layout="2"] .question-item,
    .questions-container[data-layout="4"] .question-item,
    .questions-container[data-layout="9"] .question-item,
    .questions-container[data-layout="16"] .question-item,
    .questions-container[data-layout="25"] .question-item {

        padding: 1px;
    }

    /* 调整题目内容容器 */
    .question-content {
        display: flex;
        align-items: center;
        justify-content: center;
        height: 100%;
        width: 100%;
        padding: 1px;
    }

    /* 调整题目包装器 */
    .question-wrapper {
        display: flex;
        align-items: center;
        justify-content: center;
        width: 100%;
        height: 100%;
        padding: 6px;
    }

    .type-item input[type="checkbox"] {
        width: 18px;
        height: 18px;
        margin: 0;
        padding: 0;
        flex-shrink: 0;
    }
}

/* 功能按钮容器样式 */
.button-container {
    display: flex;
    gap: 20px;
    align-items: center;
    justify-content: center;
    margin-bottom: 0px;
    width: 100%;
}

.btn {
    padding: 12px 28px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
    transition: all 0.3s ease;
    font-weight: 500;
    letter-spacing: 1px;
    min-width: 120px;
    height: 46px; /* 统一按钮高度 */
    line-height: 22px; /* 确保文本垂直居中 */
    box-sizing: border-box; /* 确保padding不会增加总高度 */
}

/* 增加主要操作按钮尺寸 */
.btn[data-action="generate"],
.btn[data-action="show-one"],
.btn[data-action="show-all"],
#start-timer {
    height: 56px;
    min-width: 150px;
    font-size: 18px;
    font-weight: 600;
    padding: 14px 32px;
}

.btn.primary {
    background-color: var(--primary-color);
    color: white;
}

.btn.secondary {
    background-color: var(--secondary-color);
    color: white;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--hover-shadow);
    opacity: 0.95;
}

/* 移动端适配 */
@media (max-width: 768px) {
    /* 确保移动端也增加主按钮尺寸 */
    .button-container .btn[data-action="generate"],
    .button-container .btn[data-action="show-one"],
    .button-container .btn[data-action="show-all"] {
        height: 50px;
        min-width: 0;
        flex: 1;
        font-size: 14px;
        padding: 10px 12px;
        max-width: 120px; /* 保持移动端按钮不要太宽 */
    }
}

/* 头部样式 */
.header {
    background: linear-gradient(135deg, #2196F3, #1976D2);
    padding: 12px 0;
    box-shadow: var(--card-shadow);
    margin-bottom: 2px;
}

.header-content {
    max-width: 90%;
    width: 90%;
    margin: 0 auto;
    text-align: center;
}

.header h1 {
    font-size: 24px;
    color: white;
    font-weight: 600;
    letter-spacing: 1px;
    margin-bottom: 4px;
}

.header p {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.9);
}

/* 尾部样式 */
.footer {
    background: white;
    padding: 24px 0;
    margin-top: 2px;
    box-shadow: var(--card-shadow);
}

.footer-content {
    max-width: 90%;
    width: 90%;
    margin: 0 auto;
    text-align: center;
}

.footer-main {
    color: #666;
    font-size: 14px;
    margin-bottom: 5px;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
    margin-bottom: 5px;
}

.footer-links a {
    color: #666;
    text-decoration: none;
    font-size: 14px;
    transition: opacity 0.3s ease;
    position: relative;
}

.footer-links a:not(:last-child)::after {
    content: '|';
    position: absolute;
    right: -12px;
    color: #999;
}

.footer-links a:hover {
    opacity: 0.8;
}

/* 美化标题样式 */
.section-title::before {
    content: '';
    display: inline-block;
    width: 4px;
    height: 20px;
    background: var(--primary-color);
    border-radius: 2px;
}

/* 分数显示样式 */
.fraction {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    vertical-align: middle;
    margin: 0 2px;
}

.fraction-line {
    width: 100%;
    height: 1px;
    background-color: var(--text-color);
    margin: 2px 0;
}

.fraction-numerator,
.fraction-denominator {
    font-size: 1.2em;
    line-height: 1;
}

/* 确保分数在题目中正确对齐 */
.question-text .fraction {
    vertical-align: middle;
    margin: 0 2px;
}

.answer .fraction {
    vertical-align: middle;
    margin: 0 2px;
}

.export-section {
    margin: 24px 0 32px 0;
    padding: 24px;
    background-color: white;
    border-radius: 12px;
    width: 100%;
    box-shadow: var(--card-shadow);
    box-sizing: border-box;
}

.export-controls {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-top: 2px;
    background: white;
    padding: 16px;
    border-radius: 12px;
    box-shadow: var(--card-shadow);
    align-items: center;
    text-align: center;
}

.export-input {
    display: flex;
    align-items: center;
    gap: 10px;
    justify-content: center;
}

.export-count-section {
    display: flex;
    align-items: center;
    gap: 10px;
}

.export-buttons-section {
    display: flex;
    align-items: center;
    gap: 10px;
}

.export-controls input {
    width: 120px;
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 18px;
    transition: all 0.3s ease;
    background: white;
    text-align: center;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    color: var(--text-color);
    font-weight: 500;
    letter-spacing: 0.5px;
}

.export-controls input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(76, 175, 80, 0.1);
    transform: translateY(-1px);
}

/* 功能按钮焦点样式 - 替换默认黑色边框 */
.btn:focus {
    outline: none;
    box-shadow: 0 0 0 5px rgba(33, 150, 243, 0.3);
    border-color: var(--secondary-color);
}

/* 主要操作按钮焦点样式 */
.btn.primary:focus {
    outline: none;
    box-shadow: 0 0 0 5px rgba(76, 175, 80, 0.3);
    border-color: #43a047;
}

/* 次要操作按钮焦点样式 */
.btn.secondary:focus {
    outline: none;
    box-shadow: 0 0 0 5px rgba(33, 150, 243, 0.3);
    border-color: #1976D2;
}

/* 题型控制按钮焦点样式 */
.type-controls button:focus {
    outline: none;
    box-shadow: 0 0 0 5px rgba(76, 175, 80, 0.2);
    border-color: var(--primary-color);
}

/* 每页题目数按钮焦点样式 */
.questions-per-page button:focus {
    outline: none;
    box-shadow: 0 0 0 5px rgba(76, 175, 80, 0.2);
    border-color: var(--primary-color);
}

.export-controls input:hover {
    border-color: var(--primary-color);
    box-shadow: 0 2px 5px rgba(0,0,0,0.08);
}

.export-controls input::placeholder {
    color: #aaa;
    font-weight: normal;
}

.export-controls .btn {
    padding: 10px 24px;
    min-width: 100px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

.export-controls .btn:hover {
    background: #43a047;
    transform: translateY(-1px);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

@media (max-width: 768px) {
    .container {
        padding: 16px;
        width: 95%;
        max-width: 95%;
    }

    .question-types-container {
        padding: 16px;
    }

    .export-section {
        margin: 16px 0 24px 0;
        padding: 16px;
        width: 100%;
    }

    .export-controls {
        padding: 12px;
    }

    .export-input {
        width: 100%;
        flex-direction: column;
        gap: 15px;
        justify-content: center;
    }

    .export-count-section {
        justify-content: center;
    }

    .export-buttons-section {
        justify-content: center;
        flex-wrap: wrap;
        gap: 10px;
    }
}

/* 导出提示框样式 */
.export-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.export-modal.show {
    opacity: 1;
    visibility: visible;
}

.export-modal-content {
    background: white;
    border-radius: 12px;
    padding: 30px;
    max-width: 450px;
    width: 90%;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    text-align: center;
    transform: scale(0.8);
    transition: transform 0.3s ease;
}

.export-modal.show .export-modal-content {
    transform: scale(1);
}

.export-modal-icon {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 30px;
    animation: modalPulse 0.6s ease-out;
}

.export-modal-icon.success {
    background: linear-gradient(135deg, #4CAF50, #45a049);
}

.export-modal-icon.error {
    background: linear-gradient(135deg, #f44336, #d32f2f);
}

.export-modal-icon.warning {
    background: linear-gradient(135deg, #ff9800, #f57c00);
}

@keyframes modalPulse {
    0% {
        transform: scale(0);
        opacity: 0;
    }
    50% {
        transform: scale(1.1);
    }
    100% {
        transform: scale(1);
        opacity: 1;
    }
}

.export-modal-title {
    font-size: 20px;
    font-weight: bold;
    color: #333;
    margin-bottom: 15px;
}

.export-modal-message {
    font-size: 14px;
    color: #666;
    line-height: 1.6;
    margin-bottom: 25px;
}

.export-modal-warning {
    background: #fff3cd;
    border: 1px solid #ffeaa7;
    border-radius: 6px;
    padding: 12px;
    margin-bottom: 20px;
    font-size: 13px;
    color: #856404;
}

.export-modal-warning::before {
    content: "⚠️ ";
    margin-right: 5px;
}

.export-modal-button {
    background: linear-gradient(135deg, #007bff, #0056b3);
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 6px;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
    min-width: 100px;
}

.export-modal-button:hover {
    background: linear-gradient(135deg, #0056b3, #004085);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 123, 255, 0.3);
}

.export-modal-button:active {
    transform: translateY(0);
}

.export-modal-button.error {
    background: linear-gradient(135deg, #dc3545, #c82333);
}

.export-modal-button.error:hover {
    background: linear-gradient(135deg, #c82333, #a71e2a);
    box-shadow: 0 4px 12px rgba(220, 53, 69, 0.3);
}

/* 倒计时样式 */
.timer-container {
    display: flex;
    align-items: center;
    gap: 1px;
    margin-left: 2px;
    border-radius: 8px;
    flex-direction: row;
    flex-wrap: nowrap;
    background: transparent;
    box-shadow: none;
}

/* 增加倒计时按钮尺寸 */
#start-timer {
    height: 56px;
    min-width: 150px;
    font-size: 18px;
    font-weight: 600;
    padding: 14px 32px;
}

.timer-inputs {
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 5px;
    border-radius: 6px;
    flex-shrink: 0;
    background: transparent;
}

.timer-inputs input {
    width: 70px;
    padding: 0 5px;
    border: 2px solid #2196F3;
    border-radius: 4px;
    text-align: center;
    font-size: 30px;
    background: white;
    height: 46px; /* 与按钮高度一致 */
    line-height: 40px;
    box-sizing: border-box;
    -webkit-appearance: auto;
    -moz-appearance: auto;
    appearance: auto;
    pointer-events: auto;
    user-select: text;
}

#timer-display {
    font-size: 2.2em;
    font-weight: bold;
    min-width: 80px;
    text-align: center;
    color: white;
    background: #2196F3;
    padding: 0 10px;
    border-radius: 6px;
    flex-shrink: 0;
    height: 46px; /* 与按钮高度一致 */
    line-height: 46px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-left: 5px;
    display: none;
}

#timer-display.warning {
    color: white;
    background: #ff4444;
    animation: blink 1s infinite;
}

@keyframes blink {
    0% { opacity: 1; }
    50% { opacity: 0.5; }
    100% { opacity: 1; }
}

/* 移动端倒计时样式调整 */
@media (max-width: 767px) {
    .timer-container {
        display: none; /* 在手机端隐藏倒计时功能 */
    }
}

/* 题目类型统计样式 */
.type-stats {
    font-size: 14px;
    color: #666;
    display: flex;
    align-items: center;
    justify-content: center;
}

.type-stats span {
    margin-right: 15px;
}

.mobile-only {
    display: block;
}

@media (min-width: 768px) {
    .mobile-only {
        display: none;
    }
    
    .question-types-container .section-title::after {
        content: attr(data-stats);
        font-size: 20px;
        color: #666;
        margin-left: 10px;
        font-weight: normal;
    }
}

@media (max-width: 767px) {
    .export-controls {
        padding: 12px;
        align-items: center;
    }
    
    .export-input {
        width: 100%;
        flex-direction: column;
        gap: 15px;
        justify-content: center;
    }

    .export-count-section {
        justify-content: center;
    }

    .export-buttons-section {
        justify-content: center;
        flex-wrap: wrap;
        gap: 10px;
    }
}

/* 确保所有数字输入框的上下箭头始终可见 */
input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button {
    opacity: 1;
    height: 30px;
    pointer-events: auto;
    position: relative;
}

/* 针对Firefox浏览器 */
input[type="number"] {
    -moz-appearance: spinner-textfield;
    appearance: spinner-textfield; /* 标准属性，确保跨浏览器兼容性 */
}

/* 特别针对计时器输入框 */
.timer-inputs input {
    width: 70px;
    padding: 0 5px;
    border: 2px solid #2196F3;
    border-radius: 4px;
    text-align: center;
    font-size: 20px;
    background: white;
    height: 46px;
    line-height: 40px;
    box-sizing: border-box;
    -webkit-appearance: auto;
    -moz-appearance: auto;
    appearance: auto;
    pointer-events: auto;
    user-select: text;
}

.timer-inputs input::-webkit-inner-spin-button,
.timer-inputs input::-webkit-outer-spin-button {
    opacity: 1 !important;
    height: 30px;
    position: relative;
    display: block;
}

/* 倒计时结束提示框样式 */
.timer-alert {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    padding: 40px 50px;
    border-radius: 20px;
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.2);
    text-align: center;
    z-index: 1000;
    animation: alertAppear 0.3s ease-out;
    min-width: 320px;
    max-width: 90%;
    border: 2px solid #2196F3;
    display: none !important; /* 确保默认隐藏 */
    visibility: hidden !important; /* 确保默认隐藏 */
    opacity: 0 !important; /* 确保默认隐藏 */
}

.timer-alert h3 {
    color: #2196F3;
    font-size: 28px;
    margin-bottom: 20px;
    font-weight: 600;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.timer-alert p {
    color: #666;
    font-size: 20px;
    margin-bottom: 30px;
    line-height: 1.6;
}

.timer-alert button {
    background: #2196F3;
    color: white;
    border: none;
    padding: 14px 32px;
    border-radius: 10px;
    font-size: 18px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
    box-shadow: 0 4px 8px rgba(33, 150, 243, 0.3);
}

.timer-alert button:hover {
    background: #1976D2;
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(33, 150, 243, 0.4);
}

/* 提示框背景遮罩 */
.timer-alert-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    z-index: 999;
    animation: overlayAppear 0.3s ease-out;
    backdrop-filter: blur(3px);
    display: none !important; /* 确保默认隐藏 */
    visibility: hidden !important; /* 确保默认隐藏 */
    opacity: 0 !important; /* 确保默认隐藏 */
}

@keyframes alertAppear {
    0% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.8);
    }
    100% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
}

@keyframes overlayAppear {
    0% {
        opacity: 0;
    }
    100% {
        opacity: 1;
    }
}

/* 移动端适配 */
@media (max-width: 768px) {
    .timer-alert {
        padding: 30px 40px;
        min-width: 280px;
        margin: 0 20px;
    }

    .timer-alert h3 {
        font-size: 24px;
        margin-bottom: 16px;
    }

    .timer-alert p {
        font-size: 18px;
        margin-bottom: 24px;
    }

    .timer-alert button {
        padding: 12px 24px;
        font-size: 16px;
    }

    /* 导出提示框移动端适配 */
    .export-modal-content {
        padding: 20px;
        max-width: 350px;
    }

    .export-modal-title {
        font-size: 18px;
    }

    .export-modal-message {
        font-size: 13px;
    }

    .export-modal-icon {
        width: 50px;
        height: 50px;
        font-size: 24px;
    }
}