/* ============================================
   驾考宝典 - 蓝色主题样式
   主色：#1966FF
   ============================================ */

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

:root {
    --primary: #1966FF;
    --primary-dark: #0d4fc7;
    --primary-light: #e8f0ff;
    --primary-gradient: linear-gradient(135deg, #1966FF 0%, #0d4fc7 100%);
    --text-color: #1a1a2e;
    --text-light: #666;
    --bg-gray: #f5f7fa;
    --border-color: #e8ecf1;
    --shadow: 0 2px 12px rgba(25, 102, 255, 0.08);
    --radius: 12px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background: var(--bg-gray);
    color: var(--text-color);
    line-height: 1.7;
}

a { text-decoration: none; color: var(--text-color); transition: color 0.3s; }
a:hover { color: var(--primary); }

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* ========== 顶部导航 ========== */
.jiakao-header {
    background: #fff;
    box-shadow: 0 2px 12px rgba(25, 102, 255, 0.06);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 2px solid var(--primary);
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 68px;
    gap: 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

.logo span {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: -0.5px;
}

.logo a { display: flex; align-items: center; gap: 10px; }

.nav {
    display: flex;
    gap: 6px;
    align-items: center;
    flex-wrap: wrap;
}

.nav a {
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s;
    color: #555;
}

.nav a i { margin-right: 4px; font-size: 13px; }

.nav a:hover,
.nav a.active {
    background: var(--primary-light);
    color: var(--primary);
}

.nav a.all-article {
    border: 1px solid var(--border-color);
}

.nav a.all-article:hover {
    border-color: var(--primary);
    background: #fff;
}

.search-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border: none;
    background: var(--bg-gray);
    color: #666;
    cursor: pointer;
    font-size: 15px;
    transition: all 0.3s;
    flex-shrink: 0;
}

.search-toggle:hover {
    background: var(--primary);
    color: #fff;
}

.menu-toggle {
    display: none;
    background: var(--primary);
    color: #fff;
    border: none;
    width: 38px;
    height: 38px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 18px;
    flex-shrink: 0;
}

/* 搜索区域 */
.search-section {
    display: none;
    background: #fff;
    padding: 15px 20px;
    border-top: 1px solid var(--border-color);
}

.search-section.show { display: block; animation: slideDown 0.3s ease; }

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

.search-form {
    display: flex;
    gap: 10px;
    max-width: 600px;
    margin: 0 auto;
}

.search-input {
    flex: 1;
    padding: 10px 18px;
    border: 2px solid var(--border-color);
    border-radius: 25px;
    font-size: 14px;
    outline: none;
    transition: border-color 0.3s;
}

.search-input:focus { border-color: var(--primary); }

.search-btn {
    background: var(--primary);
    color: #fff;
    border: none;
    padding: 10px 28px;
    border-radius: 25px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transition: background 0.3s;
    white-space: nowrap;
}

.search-btn:hover { background: var(--primary-dark); }

/* ========== 页面内容 ========== */
.page-content { padding: 25px 0; }

/* ========== 首页 Hero ========== */
.jiakao-hero {
    background: var(--primary-gradient);
    border-radius: var(--radius);
    padding: 50px 45px;
    margin-bottom: 30px;
    color: #fff;
    position: relative;
    overflow: hidden;
}

.jiakao-hero::after {
    content: '';
    position: absolute;
    right: -60px;
    top: -60px;
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: rgba(255,255,255,0.06);
}

.jiakao-hero .hero-content {
    position: relative;
    z-index: 2;
}

.jiakao-hero h1 {
    font-size: 34px;
    font-weight: 700;
    margin-bottom: 12px;
}

.jiakao-hero h1 i { margin-right: 10px; }

.jiakao-hero p {
    font-size: 17px;
    opacity: 0.9;
    margin-bottom: 20px;
    max-width: 600px;
}

.jiakao-hero .hero-stats {
    display: flex;
    gap: 40px;
}

.jiakao-hero .hero-stats .stat-item {
    text-align: center;
}

.jiakao-hero .hero-stats .stat-num {
    font-size: 28px;
    font-weight: 700;
    display: block;
}

.jiakao-hero .hero-stats .stat-label {
    font-size: 13px;
    opacity: 0.8;
}

/* ========== 区块标题 ========== */
.section-title {
    font-size: 22px;
    font-weight: 700;
    margin: 0 0 18px;
    padding-left: 14px;
    border-left: 4px solid var(--primary);
    color: var(--text-color);
}

.section-title i { color: var(--primary); margin-right: 8px; }

/* ========== 在线题库练习 - 筛选卡片 ========== */
.exam-section {
    margin-bottom: 35px;
}

.exam-filter-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 25px 30px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    margin-bottom: 20px;
}

.exam-filter-card .form-row {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr auto;
    gap: 15px;
    align-items: end;
}

.exam-filter-card .form-group {
    margin-bottom: 0;
}

.exam-filter-card .form-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 5px;
}

.exam-filter-card .form-group label i {
    color: var(--primary);
    margin-right: 4px;
}

.exam-filter-card .form-control {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 14px;
    color: var(--text-color);
    background: #fff;
    transition: border-color 0.3s;
    appearance: auto;
}

.exam-filter-card .form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(25, 102, 255, 0.08);
}

.btn-search {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 30px;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    white-space: nowrap;
}

.btn-search:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(25, 102, 255, 0.3);
}

.btn-group {
    display: flex;
    align-items: end;
}

.message-box {
    padding: 0;
    margin-top: 10px;
    font-size: 14px;
    border-radius: 8px;
    display: none;
}

.message-box.error {
    display: block;
    padding: 12px 18px;
    background: #fff3cd;
    color: #856404;
    border: 1px solid #ffc107;
}

.message-box.success {
    display: block;
    padding: 12px 18px;
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.message-box a {
    color: var(--primary);
    font-weight: 600;
}

/* ========== 加载动画 ========== */
.loading {
    text-align: center;
    padding: 40px 20px;
    color: #999;
}

.loading .spinner {
    font-size: 32px;
    color: var(--primary);
    animation: spin 1s linear infinite;
    display: inline-block;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading p {
    margin-top: 12px;
    font-size: 15px;
}

/* ========== 题目结果卡片 ========== */
.result-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 25px 30px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--border-color);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 8px;
}

.progress-fill {
    height: 100%;
    background: var(--primary-gradient);
    border-radius: 3px;
    transition: width 0.5s ease;
}

.progress-text {
    text-align: center;
    font-size: 14px;
    color: #999;
    margin-bottom: 20px;
}

/* ========== 单个题目 ========== */
.question-item {
    padding: 20px 0;
    border-bottom: 1px solid var(--border-color);
}

.question-item:last-child {
    border-bottom: none;
}

.question-item .q-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.question-item .q-number {
    font-size: 14px;
    font-weight: 600;
    color: var(--primary);
}

.question-item .q-type {
    font-size: 12px;
    padding: 2px 14px;
    background: var(--primary-light);
    color: var(--primary);
    border-radius: 12px;
}

.question-item .q-text {
    font-size: 16px;
    font-weight: 500;
    line-height: 1.6;
    margin-bottom: 10px;
}

.question-item .q-image {
    margin: 10px 0;
    text-align: center;
}

.question-item .q-image img {
    max-width: 100%;
    max-height: 200px;
    border-radius: 8px;
}

.question-item .q-options {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 12px;
}

.question-item .q-option {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 14px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    cursor: pointer;
    transition: all 0.3s;
    font-size: 14px;
}

.question-item .q-option:hover {
    border-color: var(--primary);
    background: var(--primary-light);
}

.question-item .q-option input[type="radio"] {
    width: 16px;
    height: 16px;
    accent-color: var(--primary);
    cursor: pointer;
    flex-shrink: 0;
}

.question-item .q-option-label {
    font-weight: 600;
    color: var(--primary);
}

.question-item .q-option-text {
    color: var(--text-color);
}

.question-item .q-answer-wrap {
    margin-top: 10px;
}

.question-item .q-show-answer {
    padding: 6px 18px;
    background: var(--bg-gray);
    color: var(--text-light);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.3s;
}

.question-item .q-show-answer:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: var(--primary-light);
}

.question-item .q-answer-box {
    margin-top: 10px;
    padding: 14px 18px;
    background: var(--primary-light);
    border-radius: 8px;
    border-left: 4px solid var(--primary);
}

.question-item .q-correct {
    color: #155724;
    font-size: 14px;
}

.question-item .q-correct strong {
    color: var(--primary);
}

.question-item .q-explains {
    margin-top: 6px;
    font-size: 14px;
    color: #555;
    line-height: 1.7;
}

/* ========== 驾考知识 - TAB ========== */
.knowledge-section {
    margin-bottom: 30px;
}

.knowledge-tabs {
    display: flex;
    gap: 6px;
    margin-bottom: 20px;
    background: #fff;
    padding: 6px;
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
}

.knowledge-tab {
    padding: 10px 28px;
    border: none;
    border-radius: 8px;
    background: transparent;
    color: #666;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.knowledge-tab:hover {
    color: var(--primary);
    background: var(--primary-light);
}

.knowledge-tab.active {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 4px 14px rgba(25, 102, 255, 0.25);
}

.knowledge-tab i {
    margin-right: 6px;
}

.knowledge-content {
    display: none;
}

.knowledge-content.active {
    display: block;
}

/* ========== 知识卡片网格 ========== */
.knowledge-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.knowledge-card {
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
    box-shadow: var(--shadow);
}

.knowledge-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(25, 102, 255, 0.12);
    border-color: var(--primary);
}

.knowledge-link {
    display: block;
    text-decoration: none;
    color: inherit;
}

.knowledge-thumb {
    width: 100%;
    height: 170px;
    overflow: hidden;
    background: #f5f7fa;
}

.knowledge-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s;
}

.knowledge-card:hover .knowledge-thumb img {
    transform: scale(1.03);
}

.knowledge-thumb.no-image {
    display: flex;
    align-items: center;
    justify-content: center;
    color: #ccc;
    font-size: 48px;
}

.knowledge-body {
    padding: 16px 18px;
}

.knowledge-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 8px;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.knowledge-card:hover .knowledge-title {
    color: var(--primary);
}

.knowledge-desc {
    font-size: 14px;
    color: #888;
    line-height: 1.6;
    margin-bottom: 12px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.knowledge-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    font-size: 12px;
    color: #bbb;
    padding-top: 10px;
    border-top: 1px solid #f0f0f0;
}

.knowledge-meta span {
    display: flex;
    align-items: center;
    gap: 3px;
}

.knowledge-meta i {
    font-size: 12px;
}

.knowledge-category {
    color: var(--primary);
    font-weight: 500;
}

/* ========== 分类页 - 分类标签 ========== */
.category-tabs-wrapper { margin-bottom: 20px; }

.category-tabs {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding: 12px;
    background: #fff;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
}

.category-tabs::-webkit-scrollbar { display: none; }

.category-tab {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 8px 18px;
    background: var(--bg-gray);
    color: #666;
    border-radius: 20px;
    font-size: 14px;
    white-space: nowrap;
    flex-shrink: 0;
    transition: all 0.3s;
    text-decoration: none;
}

.category-tab i { font-size: 12px; }

.category-tab:hover { background: var(--primary-light); color: var(--primary); }

.category-tab.active {
    background: var(--primary);
    color: #fff;
    font-weight: 500;
}

.category-tab .tab-count {
    font-size: 11px;
    opacity: 0.8;
    margin-left: 2px;
}

/* ========== 文章详情页 ========== */
.article-detail {
    background: #fff;
    padding: 30px 35px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.article-detail h1 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 15px;
    color: var(--text-color);
    line-height: 1.3;
}

.article-detail .meta {
    color: #999;
    font-size: 14px;
    margin-bottom: 25px;
    padding-bottom: 18px;
    border-bottom: 2px solid var(--border-color);
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.article-detail .meta i { margin-right: 4px; }

.article-detail .content {
    line-height: 1.9;
    font-size: 16px;
    color: #333;
}

.article-detail .content img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 15px 0;
}

.article-detail .content h2,
.article-detail .content h3 {
    margin: 25px 0 12px;
    color: var(--text-color);
}

.article-detail .content p { margin-bottom: 14px; }

.article-detail .content blockquote {
    border-left: 4px solid var(--primary);
    padding: 12px 18px;
    margin: 15px 0;
    background: var(--primary-light);
    border-radius: 0 6px 6px 0;
    color: #333;
}

.article-navigation {
    display: flex;
    justify-content: space-between;
    gap: 20px;
    margin-top: 25px;
    padding-top: 20px;
    border-top: 2px solid var(--border-color);
}

.article-navigation a {
    flex: 1;
    padding: 12px 18px;
    background: var(--bg-gray);
    border-radius: 8px;
    font-size: 14px;
    transition: all 0.3s;
}

.article-navigation a:hover {
    background: var(--primary-light);
    color: var(--primary);
}

.article-navigation .nav-label {
    display: block;
    font-size: 12px;
    color: #999;
    margin-bottom: 4px;
}

.article-navigation .next { text-align: right; }

/* ========== 侧边栏 ========== */
.two-col {
    display: flex;
    gap: 25px;
}

.main-content { flex: 1; min-width: 0; }

.sidebar { width: 300px; flex-shrink: 0; }

.sidebar-card {
    background: #fff;
    padding: 20px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    margin-bottom: 18px;
}

.sidebar-card h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 14px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--primary);
    color: var(--text-color);
}

.sidebar-card h3 i { color: var(--primary); margin-right: 6px; }

.hot-list {
    list-style: none;
    padding: 0;
}

.hot-list li {
    display: flex;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px dashed var(--border-color);
    gap: 10px;
}

.hot-list li:last-child { border-bottom: none; }

.hot-rank {
    width: 24px;
    height: 24px;
    line-height: 24px;
    text-align: center;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
    color: #999;
    background: var(--bg-gray);
    flex-shrink: 0;
}

.hot-rank.top1 { background: #e74c3c; color: #fff; }
.hot-rank.top2 { background: #ff9800; color: #fff; }
.hot-rank.top3 { background: var(--primary); color: #fff; }

.hot-list a {
    flex: 1;
    color: var(--text-color);
    font-size: 14px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.hot-list a:hover { color: var(--primary); }

.hot-views {
    color: #bbb;
    font-size: 12px;
    flex-shrink: 0;
}

/* ========== 分页 ========== */
.pagination {
    display: flex;
    justify-content: center;
    gap: 6px;
    margin-top: 25px;
    flex-wrap: wrap;
}

.pagination a,
.pagination span {
    padding: 8px 16px;
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 14px;
    color: #666;
    transition: all 0.3s;
}

.pagination a:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.pagination .current {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

/* ========== 空状态 ========== */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: #999;
}

.empty-state i {
    font-size: 48px;
    color: #ddd;
    display: block;
    margin-bottom: 15px;
}

/* ========== 页脚 ========== */
.jiakao-footer {
    background: #1a1a2e;
    color: #aaa;
    padding: 40px 0 20px;
    margin-top: 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 30px;
    padding-bottom: 30px;
    border-bottom: 1px solid rgba(255,255,255,0.06);
}

.footer-col h4 {
    color: #fff;
    font-size: 16px;
    margin-bottom: 14px;
}

.footer-col p,
.footer-col li {
    font-size: 13px;
    line-height: 2;
}

.footer-col ul {
    list-style: none;
}

.footer-col ul a {
    color: #aaa;
    transition: color 0.3s;
}

.footer-col ul a:hover { color: var(--primary); }

.footer-social {
    display: flex;
    gap: 12px;
    margin-top: 10px;
}

.footer-social a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: rgba(255,255,255,0.06);
    color: #aaa;
    transition: all 0.3s;
}

.footer-social a:hover {
    background: var(--primary);
    color: #fff;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    font-size: 13px;
    color: #777;
}

.footer-bottom .footer-version {
    color: #555;
    font-size: 12px;
    margin-top: 4px;
}

/* ========== 返回顶部 ========== */
.back-to-top {
    position: fixed;
    bottom: 25px;
    right: 25px;
    width: 42px;
    height: 42px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    border: none;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    box-shadow: 0 4px 16px rgba(25, 102, 255, 0.3);
    transition: all 0.3s;
    z-index: 999;
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 24px rgba(25, 102, 255, 0.4);
}

.back-to-top.show { display: flex; }

/* ========== 响应式 ========== */
@media (max-width: 992px) {
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
    .sidebar { width: 100%; }
    .two-col { flex-direction: column; }
    .exam-filter-card .form-row {
        grid-template-columns: 1fr 1fr;
    }
    .btn-group {
        grid-column: 1 / -1;
    }
}

@media (max-width: 768px) {
    .nav {
        display: none;
        flex-direction: column;
        width: 100%;
        background: #fff;
        padding: 10px 0;
        border-top: 1px solid var(--border-color);
        position: absolute;
        top: 68px;
        left: 0;
        box-shadow: 0 4px 20px rgba(0,0,0,0.06);
    }
    .nav.show { display: flex; }
    .nav a { width: 100%; padding: 12px 20px; border-radius: 0; }
    .menu-toggle { display: flex; }
    .jiakao-hero { padding: 30px 20px; }
    .jiakao-hero h1 { font-size: 24px; }
    .jiakao-hero .hero-stats { gap: 20px; flex-wrap: wrap; }
    .jiakao-hero .hero-stats .stat-num { font-size: 22px; }
    .article-detail { padding: 18px; }
    .article-detail h1 { font-size: 22px; }
    .footer-grid { grid-template-columns: 1fr; text-align: center; }
    .footer-social { justify-content: center; }
    .search-form { flex-direction: column; }
    .search-btn { text-align: center; }
    .article-navigation { flex-direction: column; }
    .exam-filter-card .form-row {
        grid-template-columns: 1fr;
    }
    .knowledge-grid {
        grid-template-columns: 1fr 1fr;
        gap: 14px;
    }
    .knowledge-thumb {
        height: 130px;
    }
    .exam-filter-card {
        padding: 18px;
    }
}

@media (max-width: 480px) {
    .knowledge-grid {
        grid-template-columns: 1fr;
    }
    .container { padding: 0 12px; }
    .article-detail h1 { font-size: 19px; }
}

/* ============================================================
   逐题模式 - 新增样式
   ============================================================ */

/* ----- 题目导航按钮 ----- */
.question-nav {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 15px;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
    flex-wrap: wrap;
}

.btn-prev,
.btn-next,
.btn-submit {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 28px;
    border: none;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-prev {
    background: var(--bg-gray);
    color: var(--text-color);
}

.btn-prev:hover {
    background: var(--border-color);
}

.btn-next {
    background: var(--primary);
    color: #fff;
}

.btn-next:hover {
    background: var(--primary-dark);
    transform: translateX(2px);
}

.btn-submit {
    background: #27ae60;
    color: #fff;
}

.btn-submit:hover {
    background: #219a52;
    transform: scale(1.02);
}

/* ----- 题目标记 ----- */
.question-marks {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: 15px;
    padding-top: 15px;
    border-top: 1px solid var(--border-color);
    align-items: center;
}

.marks-label {
    font-size: 13px;
    color: #999;
    margin-right: 8px;
}

.mark-item {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--bg-gray);
    color: #999;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.mark-item:hover {
    transform: scale(1.1);
    border-color: var(--primary);
}

.mark-item.answered {
    background: var(--primary-light);
    color: var(--primary);
}

.mark-item.current {
    border-color: var(--primary);
    background: var(--primary);
    color: #fff;
    transform: scale(1.1);
}

/* ----- 结果弹窗 ----- */
.result-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(4px);
}

.result-modal {
    background: #fff;
    border-radius: 16px;
    padding: 35px 40px;
    max-width: 560px;
    width: 90%;
    max-height: 85vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    animation: modalIn 0.3s ease;
}

@keyframes modalIn {
    from { opacity: 0; transform: scale(0.9) translateY(20px); }
    to { opacity: 1; transform: scale(1) translateY(0); }
}

.result-icon {
    font-size: 56px;
    text-align: center;
    margin-bottom: 10px;
}

.result-modal h2 {
    text-align: center;
    font-size: 24px;
    color: var(--text-color);
    margin-bottom: 18px;
}

.result-stats {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr;
    gap: 10px;
    margin-bottom: 20px;
}

.result-stat-item {
    text-align: center;
    padding: 12px 10px;
    background: var(--bg-gray);
    border-radius: 8px;
}

.result-stat-item .stat-label {
    display: block;
    font-size: 12px;
    color: #999;
}

.result-stat-item .stat-value {
    display: block;
    font-size: 22px;
    font-weight: 700;
}

.result-detail {
    max-height: 200px;
    overflow-y: auto;
    margin-bottom: 20px;
    padding: 10px 0;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.result-detail-item {
    padding: 5px 0;
    font-size: 14px;
    line-height: 1.6;
    border-bottom: 1px solid #f5f5f5;
}

.result-detail-item:last-child {
    border-bottom: none;
}

.btn-result-close {
    display: block;
    width: 100%;
    padding: 12px;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-result-close:hover {
    background: var(--primary-dark);
}

/* ----- 题目选项交互优化 ----- */
.question-item .q-option {
    cursor: pointer;
    transition: all 0.2s;
}

.question-item .q-option:hover {
    border-color: var(--primary);
    background: var(--primary-light);
}

.question-item .q-option input[type="radio"]:checked + .q-option-label + .q-option-text {
    color: var(--primary);
}

.question-item .q-option:has(input:checked) {
    border-color: var(--primary);
    background: var(--primary-light);
}

/* 查看答案按钮优化 */
.q-show-answer {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 18px;
    background: var(--bg-gray);
    color: var(--text-light);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.3s;
}

.q-show-answer:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: var(--primary-light);
}

/* ----- 响应式 ----- */
@media (max-width: 768px) {
    .result-stats {
        grid-template-columns: 1fr 1fr;
    }
    
    .question-nav {
        flex-direction: column;
        gap: 10px;
    }
    
    .btn-prev,
    .btn-next,
    .btn-submit {
        width: 100%;
        justify-content: center;
    }
    
    .result-modal {
        padding: 25px 20px;
    }
    
    .mark-item {
        width: 28px;
        height: 28px;
        font-size: 11px;
    }
}

@media (max-width: 480px) {
    .result-stats {
        grid-template-columns: 1fr 1fr;
        gap: 6px;
    }
    
    .result-stat-item .stat-value {
        font-size: 18px;
    }
    
    .result-detail-item {
        font-size: 13px;
    }
}
/* ============================================================
   手机版：隐藏TAB图标
   ============================================================ */
@media (max-width: 768px) {
    .knowledge-tab i {
        display: none;
    }
    .knowledge-tab {
        padding: 8px 14px;
        font-size: 13px;
    }
}