/* =============================================
   在线考试系统 - 全新UI美化版
   版本: 2.0
   设计: 现代、简洁、专业
   ============================================= */

/* ===== CSS 变量 ===== */
:root {
    --primary: #4f46e5;
    --primary-light: #6366f1;
    --primary-dark: #3730a3;
    --primary-gradient: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
    --primary-soft: #eef2ff;
    
    --secondary: #0ea5e9;
    --secondary-light: #38bdf8;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #6366f1;
    
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    
    --bg-body: #f1f5f9;
    --bg-card: #ffffff;
    --bg-soft: #f8fafc;
    
    --border: #e2e8f0;
    --border-light: #f1f5f9;
    
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.04);
    
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 20px;
}

/* ===== 基础样式 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-body);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    width: 100%;
}

/* ===== 导航栏 ===== */
.navbar {
    background: var(--primary-gradient);
    color: white;
    padding: 0;
    box-shadow: 0 4px 20px rgba(79, 70, 229, 0.3);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 64px;
}

.logo {
    font-size: 1.2rem;
    font-weight: 700;
    color: white;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
    letter-spacing: -0.02em;
    white-space: nowrap;
}

.logo i {
    font-size: 1.5rem;
    background: rgba(255,255,255,0.2);
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 10px;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-links a {
    color: rgba(255,255,255,0.85);
    text-decoration: none;
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    transition: all 0.2s;
    font-size: 0.9rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 6px;
    white-space: nowrap;
}

.nav-links a:hover {
    color: white;
    background: rgba(255,255,255,0.15);
}

.user-info {
    padding: 6px 14px;
    background: rgba(255,255,255,0.12);
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 6px;
    color: white;
    font-weight: 500;
    margin-left: 8px;
}

.btn-logout {
    background: rgba(239, 68, 68, 0.2) !important;
    color: white !important;
}

.btn-logout:hover {
    background: rgba(239, 68, 68, 0.4) !important;
}

/* 汉堡菜单 */
.hamburger-menu {
    display: none;
    background: rgba(255,255,255,0.12);
    border: none;
    color: white;
    font-size: 1.3rem;
    cursor: pointer;
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    transition: background-color 0.2s;
}

.hamburger-menu:hover {
    background: rgba(255,255,255,0.2);
}

/* ===== 按钮样式 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 22px;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.2s;
    line-height: 1.4;
}

.btn:hover {
    transform: translateY(-1px);
}

.btn-primary {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 4px 12px rgba(79, 70, 229, 0.3);
}

.btn-primary:hover {
    box-shadow: 0 6px 20px rgba(79, 70, 229, 0.4);
}

.btn-secondary {
    background: var(--secondary);
    color: white;
    box-shadow: 0 4px 12px rgba(14, 165, 233, 0.3);
}

.btn-secondary:hover {
    background: #0284c7;
    box-shadow: 0 6px 20px rgba(14, 165, 233, 0.4);
}

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

.btn-success:hover {
    background: #059669;
}

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

.btn-danger:hover {
    background: #dc2626;
}

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

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

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

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
}

.btn-ghost:hover {
    background: var(--bg-soft);
    color: var(--text-primary);
}

.btn-sm {
    padding: 6px 14px;
    font-size: 0.85rem;
}

.btn-lg {
    padding: 14px 30px;
    font-size: 1.05rem;
}

.btn-block {
    display: flex;
    width: 100%;
}

/* ===== 首页 ===== */
.hero {
    padding: 80px 0 60px;
    text-align: center;
    background: linear-gradient(180deg, #eef2ff 0%, var(--bg-body) 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 50%, rgba(79,70,229,0.03) 0%, transparent 50%);
    pointer-events: none;
}

.hero h1 {
    font-size: 2.8rem;
    font-weight: 800;
    margin-bottom: 16px;
    color: var(--text-primary);
    line-height: 1.2;
    letter-spacing: -0.03em;
}

.hero h1 span {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
    margin: 50px 0;
}

.feature {
    background: var(--bg-card);
    padding: 36px 28px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

.feature::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--primary-gradient);
    opacity: 0;
    transition: opacity 0.3s;
}

.feature:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl);
}

.feature:hover::before {
    opacity: 1;
}

.feature i {
    font-size: 2.5rem;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 20px;
}

.feature h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.feature p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

/* ===== 系统信息 ===== */
.system-info {
    padding: 60px 0;
}

.info-section {
    margin-bottom: 60px;
}

.info-section h2 {
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 24px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.info-section h2 i {
    color: var(--primary);
}

.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}

.info-card {
    background: var(--bg-card);
    padding: 24px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border);
    transition: all 0.2s;
}

.info-card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--primary-light);
}

.info-card h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 14px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.info-card h3 i {
    color: var(--primary);
}

.info-card ul {
    list-style: none;
    padding-left: 0;
}

.info-card li {
    padding: 8px 0;
    border-bottom: 1px solid var(--border-light);
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.info-card li:last-child {
    border-bottom: none;
}

.rules {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 16px;
}

.rule {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    background: var(--bg-card);
    padding: 20px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border);
    transition: all 0.2s;
}

.rule:hover {
    box-shadow: var(--shadow-md);
}

.rule i {
    font-size: 1.5rem;
    color: var(--primary);
    margin-top: 4px;
    flex-shrink: 0;
}

.rule h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text-primary);
}

.rule p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ===== 认证页面 ===== */
.auth-container {
    min-height: calc(100vh - 64px - 80px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 60px 24px;
}

.auth-card {
    background: var(--bg-card);
    padding: 44px;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 460px;
    border: 1px solid var(--border);
}

.auth-card h2 {
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.auth-subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 32px;
}

/* ===== 表单样式 ===== */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 6px;
    font-weight: 500;
    font-size: 0.9rem;
    color: var(--text-primary);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    color: var(--text-primary);
    background: var(--bg-card);
    transition: all 0.2s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.form-help {
    display: block;
    margin-top: 4px;
    color: var(--text-muted);
    font-size: 0.85rem;
}

.password-toggle {
    position: relative;
}

.btn-toggle-password {
    position: absolute;
    right: 10px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 4px;
}

.form-actions {
    margin-top: 28px;
}

.auth-links {
    text-align: center;
    margin: 20px 0;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.auth-links a {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
}

.auth-links a:hover {
    text-decoration: underline;
}

.auth-notice {
    margin-top: 24px;
    padding: 20px;
    background: var(--primary-soft);
    border-radius: var(--radius-md);
    border-left: 4px solid var(--primary);
}

.auth-notice h4 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.auth-notice ul {
    list-style: none;
    padding-left: 0;
}

.auth-notice li {
    padding: 4px 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ===== 提示消息 ===== */
.flash-messages {
    margin: 16px 0;
}

.flash-message {
    padding: 14px 18px;
    border-radius: var(--radius-sm);
    margin-bottom: 10px;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.flash-message::before {
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
}

.flash-message:contains('成功')::before,
.flash-message:contains('成功')::before {
    content: '\f00c';
    color: var(--success);
}

.flash-message:contains('错误')::before,
.flash-message:contains('失败')::before {
    content: '\f00d';
    color: var(--danger);
}

.alert {
    padding: 14px 18px;
    border-radius: var(--radius-sm);
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.9rem;
    border: none;
}

.alert-error {
    background: #fef2f2;
    color: #991b1b;
    border-left: 4px solid var(--danger);
}

.alert-success {
    background: #f0fdf4;
    color: #166534;
    border-left: 4px solid var(--success);
}

/* ===== 仪表板 ===== */
.dashboard {
    padding: 40px 0;
}

.dashboard-header {
    margin-bottom: 36px;
}

.dashboard-header h1 {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 12px;
}

.dashboard-header h1 i {
    color: var(--primary);
}

.dashboard-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.stat-card {
    background: var(--bg-card);
    padding: 28px 24px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border);
    position: relative;
    overflow: hidden;
    transition: all 0.3s;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
}

.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.stat-card i {
    font-size: 2rem;
    margin-bottom: 16px;
    display: inline-block;
}

.stat-card:nth-child(1)::before { background: linear-gradient(90deg, var(--primary), var(--primary-light)); }
.stat-card:nth-child(1) i { color: var(--primary); }
.stat-card:nth-child(2)::before { background: linear-gradient(90deg, #f472b6, #fb7185); }
.stat-card:nth-child(2) i { color: #f472b6; }
.stat-card:nth-child(3)::before { background: linear-gradient(90deg, #38bdf8, #818cf8); }
.stat-card:nth-child(3) i { color: #38bdf8; }
.stat-card:nth-child(4)::before { background: linear-gradient(90deg, #34d399, #60a5fa); }
.stat-card:nth-child(4) i { color: #34d399; }

.stat-card h3 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.stat-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin: 0;
}

.dashboard-actions {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.action-card {
    background: var(--bg-card);
    padding: 32px 28px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border);
    text-align: center;
    transition: all 0.3s;
    position: relative;
    overflow: hidden;
}

.action-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--primary-gradient);
}

.action-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.action-card i {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: 20px;
}

.action-card h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.action-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 20px;
    line-height: 1.5;
}

.action-card .btn {
    padding: 10px 28px;
}

/* 学生概览 */
.student-overview {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 16px;
    margin-bottom: 32px;
}

.overview-card {
    background: var(--bg-card);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 16px;
    border: 1px solid var(--border);
    transition: all 0.2s;
}

.overview-card:hover {
    box-shadow: var(--shadow-md);
}

.overview-card i {
    font-size: 2rem;
    color: var(--primary);
}

.overview-card div {
    flex: 1;
}

.overview-card strong {
    display: block;
    color: var(--text-secondary);
    font-size: 0.8rem;
    font-weight: 500;
    margin-bottom: 4px;
}

.overview-card span {
    display: block;
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 700;
}

/* ===== 区块 ===== */
.dashboard-sections {
    display: grid;
    gap: 28px;
}

.section {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 28px;
    border: 1px solid var(--border);
}

.section h2 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.section h2 i {
    color: var(--primary);
}

/* 学生信息 */
.student-info {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 28px;
    margin-bottom: 32px;
    border: 1px solid var(--border);
}

.student-info h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.student-info h3 i {
    color: var(--primary);
}

.info-item {
    padding: 12px 16px;
    background: var(--bg-soft);
    border-radius: var(--radius-sm);
    border-left: 4px solid var(--primary);
}

.info-item strong {
    color: var(--text-primary);
    margin-right: 8px;
    font-weight: 600;
}

/* 快速统计 */
.quick-stats h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.quick-stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 14px;
}

.quick-stat {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 16px;
    background: var(--bg-soft);
    border-radius: var(--radius-sm);
    border-left: 4px solid var(--primary);
    transition: all 0.2s;
}

.quick-stat:hover {
    box-shadow: var(--shadow-sm);
}

.quick-stat i {
    font-size: 1.5rem;
    color: var(--primary);
}

.quick-stat div {
    flex: 1;
}

.quick-stat strong {
    display: block;
    color: var(--text-secondary);
    font-size: 0.8rem;
    font-weight: 500;
    margin-bottom: 2px;
}

.quick-stat span {
    display: block;
    color: var(--text-primary);
    font-size: 1.3rem;
    font-weight: 700;
}

/* 最近活动 */
.recent-activity {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 28px;
    border: 1px solid var(--border);
}

.recent-activity h2 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.recent-activity h2 i {
    color: var(--primary);
}

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

.empty-state i {
    font-size: 3.5rem;
    color: var(--border);
    margin-bottom: 16px;
}

.empty-state p {
    font-size: 1rem;
    color: var(--text-muted);
}

/* ===== 表格 ===== */
.table-container {
    background: var(--bg-card);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border);
    overflow: hidden;
}

.table-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.table-header h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.table-actions {
    display: flex;
    gap: 8px;
}

.table-responsive {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.table {
    width: 100%;
    border-collapse: collapse;
    min-width: 600px;
}

.table th {
    padding: 12px 16px;
    text-align: left;
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-secondary);
    background: var(--bg-soft);
    border-bottom: 1px solid var(--border);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.table td {
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-light);
    font-size: 0.9rem;
    color: var(--text-primary);
}

.table tr:last-child td {
    border-bottom: none;
}

.table tr:hover {
    background: var(--primary-soft);
}

.table-actions-cell {
    display: flex;
    gap: 8px;
}

/* ===== 图表 ===== */
.dashboard-charts {
    margin-bottom: 32px;
}

.chart-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(380px, 1fr));
    gap: 20px;
    margin-bottom: 20px;
}

.chart-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 24px;
    border: 1px solid var(--border);
}

.chart-card canvas {
    width: 100% !important;
    height: 300px !important;
}

/* ===== 考试页面 ===== */
.exam-container {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 32px;
    margin: 24px 0;
    border: 1px solid var(--border);
}

.exam-header {
    text-align: center;
    margin-bottom: 28px;
    padding-bottom: 20px;
    border-bottom: 2px solid var(--border);
}

.exam-header h2 {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.exam-info {
    display: flex;
    justify-content: center;
    gap: 24px;
    margin-top: 16px;
    flex-wrap: wrap;
}

.exam-info-item {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.timer {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--danger);
    margin-bottom: 16px;
    text-align: center;
}

.question-list {
    margin: 24px 0;
}

.question-item {
    margin-bottom: 24px;
    padding: 20px;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    background: var(--bg-soft);
}

.question-number {
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.question-text {
    font-size: 1.05rem;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.options-list {
    margin: 12px 0;
}

.option-item {
    margin-bottom: 8px;
    padding: 10px 14px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--bg-card);
    cursor: pointer;
    transition: all 0.2s;
}

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

.option-item.selected {
    border-color: var(--primary);
    background: #eef2ff;
}

.option-label {
    font-weight: 600;
    margin-right: 10px;
    color: var(--primary);
}

.option-radio, .option-checkbox {
    margin-right: 8px;
    accent-color: var(--primary);
}

/* ===== 页脚 ===== */
footer {
    background: #1e293b;
    color: rgba(255,255,255,0.6);
    text-align: center;
    padding: 24px 0;
    margin-top: auto;
    font-size: 0.9rem;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .hamburger-menu {
        display: block;
    }
    
    .navbar .container {
        height: 56px;
    }
    
    .nav-links {
        position: fixed;
        top: 56px;
        left: 0;
        right: 0;
        background: var(--primary-dark);
        flex-direction: column;
        align-items: stretch;
        padding: 12px;
        transform: translateY(-110%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
        z-index: 999;
        box-shadow: var(--shadow-xl);
    }
    
    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-links a {
        padding: 12px 16px;
        border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    
    .user-info {
        margin-left: 0;
        text-align: center;
        justify-content: center;
        padding: 12px;
    }
    
    .hero h1 {
        font-size: 1.8rem;
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .auth-card {
        padding: 28px 20px;
    }
    
    .table-header {
        flex-direction: column;
        gap: 12px;
        align-items: stretch;
    }
    
    .table-actions {
        justify-content: flex-start;
    }
    
    .exam-info {
        flex-direction: column;
        align-items: center;
        gap: 8px;
    }
    
    .quick-stats-grid {
        grid-template-columns: 1fr;
    }
}

/* ===== 打印 ===== */
@media print {
    .navbar, .exam-footer, .no-print, footer {
        display: none !important;
    }
    
    .exam-container {
        box-shadow: none;
        border: 1px solid #ddd;
    }
    
    .question-item {
        page-break-inside: avoid;
    }
}