/* 
 * 主样式文件 - 导入所有拆分后的CSS模块
 * 为了便于维护，样式已拆分为多个文件：
 * - base.css: 基础样式（变量、全局样式、导航栏等）
 * - components.css: 组件样式（按钮、表单、卡片等）
 * - admin.css: 管理页面样式
 * - pages.css: 页面特定样式（答题页、排行榜等）
 * - responsive.css: 响应式样式
 */

@import url('css/base.css');
@import url('css/components.css');
@import url('css/admin.css');
@import url('css/pages.css');
@import url('css/responsive.css');

:root {
    --primary-color: #1e3a8a;
    --secondary-color: #3b82f6;
    --accent-color: #60a5fa;
    --bg-color: #f1f5f9;
    --text-color: #1e293b;
    --border-color: #cbd5e1;
    --success-color: #10b981;
    --error-color: #ef4444;
    --warning-color: #f59e0b;
}

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

/* 链接样式全局设置 */
a {
    color: #666;
    text-decoration: none;
    transition: color 0.3s;
}

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

/* 导航栏 */
.navbar {
    background: white;
    border-bottom: 1px solid #e0e0e0;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo a {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 1.5rem;
    align-items: center;
}

.nav-menu a {
    color: #666;
    text-decoration: none;
    transition: color 0.3s;
    font-weight: 500;
}

.nav-menu a:hover {
    color: var(--primary-color);
}

.fireworks-btn {
    background: var(--primary-color);
    color: white !important;
    padding: 0.5rem 1rem;
    border-radius: 0;
    transition: background 0.3s;
}

.fireworks-btn:hover {
    background: #1e40af;
}

/* 容器 */
.container {
    max-width: 1400px;
    margin: 2rem auto;
    padding: 0 2rem;
    position: relative;
    flex: 1;
}

/* 烟花画布 */
#fireworksCanvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none; /* 默认不可交互 */
    z-index: 9999;
    background: transparent;
    cursor: pointer; /* 提示用户可点击 */
}

/* 主内容区域 */
.main-content {
    background: white;
    border-radius: 0;
    padding: 1.5rem;
    border: none;
    margin-bottom: 2rem;
}

.main-content h1 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    text-align: center;
    font-size: 2rem;
}

.subtitle {
    text-align: center;
    color: #666;
    margin-bottom: 1.5rem;
    font-size: 1rem;
}

/* 提示框 */
.alert {
    padding: 1rem;
    border-radius: 0;
    margin-bottom: 1.5rem;
}

.alert-error {
    background-color: #fee;
    color: var(--error-color);
    border: 1px solid #fcc;
}

.alert-success {
    background-color: #efe;
    color: var(--success-color);
    border: 1px solid #cfc;
}

.alert-link {
    color: inherit;
    text-decoration: none;
}

.alert-link:hover {
    text-decoration: underline;
}

/* 表单样式 */
.message-form-container {
    background: white;
    padding: 1.5rem;
    border-radius: 0;
    margin-bottom: 2rem;
    border: none;
    max-width: 100%;
    width: 100%;
}

.message-form-container h2 {
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-color);
}

.required {
    color: var(--error-color);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid var(--border-color);
    border-radius: 0;
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

/* 修复textarea拖拽导致的宽度变化问题 */
.form-group textarea {
    resize: vertical; /* 只允许垂直方向调整大小 */
    min-height: 120px;
    max-width: 100%; /* 确保最大宽度不超过容器 */
    box-sizing: border-box; /* 包含padding和border在内 */
}

/* 编辑留言时的textarea特殊处理 */
.edit-textarea {
    resize: vertical !important;
    min-height: 120px;
    max-width: 100% !important;
    box-sizing: border-box !important;
}

.char-count {
    text-align: right;
    color: #999;
    font-size: 0.9rem;
    margin-top: 0.5rem;
}

/* 网址输入框包装器 */
.website-input-wrapper {
    position: relative;
}

/* 网址建议下拉框 */
.website-suggestions {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: white;
    border: 2px solid var(--primary-color);
    border-top: none;
    max-height: 300px;
    overflow-y: auto;
    z-index: 1000;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.suggestion-item {
    padding: 0.75rem;
    cursor: pointer;
    border-bottom: 1px solid var(--border-color);
    transition: background-color 0.2s;
}

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

.suggestion-item:hover,
.suggestion-item.selected {
    background-color: var(--bg-color);
}

.suggestion-name {
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 0.25rem;
}

.suggestion-url {
    font-size: 0.85rem;
    color: #666;
    word-break: break-all;
}

/* 按钮 */
.btn {
    padding: 0.75rem 2rem;
    border: none;
    border-radius: 0;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    font-family: inherit;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    border-radius: 0;
    padding: 0.5rem 1rem;
    transition: background 0.3s;
}

.btn-primary:hover {
    background: #1e40af;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

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

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

/* 留言列表 */
.messages-container {
    margin-top: 2rem;
    width: 100%;
}

.messages-container h2 {
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

.message-count {
    font-size: 1rem;
    color: #999;
    font-weight: normal;
}

.messages-list {
    display: grid;
    gap: 1.5rem;
    grid-template-columns: 1fr;
    width: 100%;
}

.message-item {
    background: white;
    padding: 1rem;
    border-radius: 0;
    border: none;
    margin-bottom: 1rem;
    max-width: 100%;
    width: 100%;
}

.message-item:hover {
    outline: 2px solid var(--primary-color);
}

.message-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.message-nickname {
    font-weight: bold;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.message-nickname a {
    color: var(--primary-color);
    text-decoration: none;
}

.message-nickname a:hover {
    text-decoration: underline;
}

.message-time {
    color: #999;
    font-size: 0.9rem;
}

.message-content {
    color: var(--text-color);
    line-height: 1.8;
    white-space: pre-wrap;
    padding: 0;
    margin: 0;
    text-indent: 0;
}

.no-messages {
    text-align: center;
    padding: 3rem;
    color: #999;
    font-size: 1.1rem;
}

/* 管理页面样式 */
.admin-content {
    background: white;
    border-radius: 0;
    padding: 1.5rem;
    border: none;
    margin-bottom: 2rem;
}

.admin-login {
    max-width: 400px;
    margin: 3rem auto;
}

.admin-login h1 {
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.login-form {
    margin-top: 2rem;
}

.admin-welcome {
    color: #666;
    margin-bottom: 1.5rem;
}

/* 统计信息 */
.admin-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-item {
    background: var(--primary-color);
    padding: 1rem;
    border-radius: 0;
    text-align: center;
    color: white;
}

.stat-label {
    display: block;
    font-size: 0.9rem;
    opacity: 0.9;
    margin-bottom: 0.5rem;
}

.stat-value {
    display: block;
    font-size: 2rem;
    font-weight: bold;
}

/* 筛选器 */
.admin-filters {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 0.5rem 1.5rem;
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 0;
    text-decoration: none;
    color: var(--text-color);
    transition: all 0.3s;
}

.filter-btn:hover,
.filter-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* 管理员留言列表 */
.admin-messages {
    display: grid;
    gap: 1rem;
}

.admin-message-item {
    background: white;
    padding: 1rem;
    border-radius: 0;
    border: none;
    border-left: 4px solid var(--border-color);
    margin-bottom: 1rem;
}

.admin-message-item.status-0 {
    border-left-color: var(--warning-color);
}

.admin-message-item.status-1 {
    border-left-color: var(--success-color);
}

.admin-message-item.status-2 {
    border-left-color: #999;
    opacity: 0.7;
}

.admin-message-item .message-header {
    margin-bottom: 1rem;
}

.message-ip {
    color: #999;
    font-size: 0.85rem;
}

.badge {
    padding: 0.25rem 0.75rem;
    border-radius: 0;
    font-size: 0.85rem;
    font-weight: 600;
}

.badge-pending {
    background-color: #fff3cd;
    color: #856404;
}

.badge-approved {
    background-color: #d4edda;
    color: #155724;
}

.badge-deleted {
    background-color: #f8d7da;
    color: #721c24;
}

.message-actions {
    margin-top: 1rem;
    display: flex;
    gap: 0.5rem;
}

/* 管理扩展区域 */
.admin-panels {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.admin-card {
    background: #f8fafc;
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    margin-top: 2rem;
}

.card-tip {
    font-size: 0.9rem;
    color: #666;
    margin-bottom: 1rem;
}

.admin-table {
    width: 100%;
    display: flex;
    flex-direction: column;
    border: 1px solid var(--border-color);
}

.table-row {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1.5fr;
    gap: 1rem;
    padding: 0.75rem 1rem;
    border-bottom: 1px solid var(--border-color);
    align-items: center;
}

.table-head {
    background: var(--primary-color);
    color: white;
    font-weight: bold;
}

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

.reset-form {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    align-items: center;
}

.reset-form input {
    flex: 1;
    min-width: 120px;
}

.tag {
    display: inline-block;
    padding: 0.1rem 0.4rem;
    font-size: 0.75rem;
    border-radius: 999px;
    margin-left: 0.5rem;
}

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

.tag-hidden {
    background: #f87171;
    color: white;
}

.quiz-list {
    margin-top: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.quiz-item {
    background: white;
    border: 1px solid var(--border-color);
    padding: 1.5rem;
}

.quiz-item-hidden {
    opacity: 0.8;
    border-style: dashed;
}

.quiz-item-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.quiz-item-time {
    font-size: 0.85rem;
    color: #999;
}

.quiz-item-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1rem;
}

.quiz-edit-form textarea {
    min-height: 120px;
}

/* 答题页面 */
.quiz-page {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.quiz-page .subtitle {
    margin-bottom: 0.5rem;
    color: #64748b;
}

.quiz-grid {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

details.quiz-card {
    background: white;
    border: 1px solid var(--border-color);
    padding: 1.25rem 1.5rem;
    width: 100%;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

details.quiz-card[open] {
    border-color: var(--primary-color);
    box-shadow: 0 4px 20px rgba(30, 58, 138, 0.08);
}

details.quiz-card summary {
    cursor: pointer;
    list-style: none;
    outline: none;
    display: block;
    width: 100%;
    padding: 0;
    margin: 0;
}

details.quiz-card summary::-webkit-details-marker {
    display: none;
}

details.quiz-card summary:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 4px;
}

.quiz-card-header {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    align-items: flex-start;
    flex-wrap: wrap;
}

.quiz-header-content {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
}

.quiz-card-title {
    font-weight: 600;
    color: var(--primary-color);
    font-size: 1.05rem;
}

.quiz-card-author {
    font-size: 0.9rem;
    color: #94a3b8;
}

.quiz-header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.quiz-score-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.15rem 0.65rem;
    border: 1px solid var(--border-color);
    border-radius: 999px;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--primary-color);
}

.quiz-toggle-icon {
    font-size: 0.9rem;
    color: #94a3b8;
    transition: transform 0.2s ease;
}

details.quiz-card[open] .quiz-toggle-icon {
    transform: rotate(180deg);
    color: var(--primary-color);
}

.quiz-card-body {
    margin-top: 1rem;
    border-top: 1px solid #e2e8f0;
    padding-top: 1rem;
}

.quiz-prompt {
    margin-bottom: 1.25rem;
    line-height: 1.8;
    color: var(--text-color);
    white-space: pre-wrap;
    word-break: break-word;
}

.quiz-prompt img {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 1rem 0;
}

.quiz-answer-form .form-group {
    margin-bottom: 0.75rem;
}

.quiz-answer-form input[type="text"] {
    border-width: 1px;
}

.quiz-feedback {
    margin-top: 1rem;
    padding: 0.75rem 1rem;
    border: 1px solid transparent;
    border-radius: 0.25rem;
    background: #f8fafc;
}

.quiz-feedback-success {
    background: #ecfdf5;
    color: var(--success-color);
    border-color: #bbf7d0;
}

.quiz-feedback-error {
    background: #fef2f2;
    color: var(--error-color);
    border-color: #fecaca;
}

.quiz-page .no-messages {
    margin-top: 1rem;
    border: 1px dashed var(--border-color);
    padding: 2rem;
    background: white;
}

/* 页脚 */
.footer {
    text-align: center;
    padding: 1.5rem;
    color: #666;
    margin-top: auto;
    border-top: 1px solid #e0e0e0;
    background: white;
    flex-shrink: 0;
}

.message-edit-form {
    margin-top: 1rem;
    padding: 1rem;
    background: #f8f9fa;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    max-width: 100%;
    width: 100%;
    box-sizing: border-box;
}

.message-edit-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
    justify-content: flex-end;
}

.edit-timer {
    font-size: 0.85rem;
    color: var(--warning-color);
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.edited-indicator {
    color: var(--warning-color);
    margin-left: 0.5rem;
}

/* 用户系统样式 */
.user-info-panel .card {
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
}

.user-info-panel .card-body {
    padding: 1rem;
}

/* 用户名片样式 */
.user-card {
    display: flex;
    align-items: flex-start;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    padding: 1rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.user-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.user-card-avatar {
    flex-shrink: 0;
    margin-right: 1rem;
}

.user-avatar-img {
    width: 64px;
    height: 64px;
    border-radius: 0;
    border: 3px solid var(--border-color);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.user-card-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    position: relative;
    padding-top: 8px;
}

.user-card-name {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 0.25rem;
}

.user-card-score {
    font-size: 0.9rem;
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: 0.75rem;
}

.user-card-logout {
    font-size: 0.8rem;
    color: #666;
    text-decoration: none;
    align-self: flex-start;
    padding: 0.25rem 0.75rem;
    border: 1px solid #e0e0e0;
    border-radius: 0.25rem;
    background: #f8f9fa;
    transition: all 0.3s ease;
}

.user-card-logout:hover {
    background: #e9ecef;
    color: var(--primary-color);
    text-decoration: none;
}

.quiz-header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.quiz-score-badge {
    background: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 0;
    font-size: 0.85rem;
    font-weight: bold;
    white-space: nowrap;
}

/* 注册登录页面样式 */
.card {
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.card-header {
    background: #f8f9fa;
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
    border-radius: 0.5rem 0.5rem 0 0;
}

.card-header h3 {
    margin: 0;
    color: var(--primary-color);
}

.card-body {
    padding: 1.5rem;
}

.form-label {
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.form-text {
    font-size: 0.875rem;
    color: #6c757d;
}

.input-group {
    display: flex;
    flex-wrap: wrap; /* 允许换行，但在宽度足够时单行 */
    gap: 0;
}

.input-group .form-control {
    flex: 1;
    min-width: 0; /* 防止flex子项溢出 */
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
}

.input-group .btn {
    flex-shrink: 0; /* 防止按钮被压缩 */
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
    white-space: nowrap; /* 防止按钮文字换行 */
    min-width: fit-content; /* 确保按钮有足够宽度 */
}

/* 在宽度足够时保持单行显示 */
@media (min-width: 576px) {
    .input-group {
        flex-wrap: nowrap; /* 宽度足够时不换行 */
    }
}

/* 验证码按钮特殊样式 */
.input-group .btn-outline-secondary {
    font-size: 0.9rem; /* 稍小的字体以适应内容 */
    padding: 0.5rem 0.75rem; /* 调整内边距 */
}

.btn-outline-secondary {
    color: #6c757d;
    border: 1px solid #6c757d;
    background: white;
}

.btn-outline-secondary:hover {
    background: #6c757d;
    color: white;
}

.d-grid {
    display: grid;
}

.text-center {
    text-align: center;
}

/* 表单链接样式 */
.form-links {
    padding: 1rem;
    background: #f8f9fa;
    border-radius: 0.5rem;
    margin-top: 1.5rem;
}

.form-links div {
    margin-bottom: 0.5rem;
}

.form-links div:last-child {
    margin-bottom: 0;
}

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

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

.nav-tabs {
    border-bottom: 1px solid #dee2e6;
    margin-bottom: 1.5rem;
}

.nav-tabs {
    border-bottom: 2px solid var(--border-color);
    margin-bottom: 1.5rem;
    display: flex;
    gap: 0;
}

.nav-tabs .nav-item {
    margin-bottom: 0;
}

.nav-tabs .nav-link {
    margin-bottom: -2px;
    background: none;
    border: 2px solid transparent;
    border-top-left-radius: 0.5rem;
    border-top-right-radius: 0.5rem;
    color: #666;
    padding: 0.75rem 1.5rem;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

.nav-tabs .nav-link:hover {
    color: var(--primary-color);
    background-color: #f8f9fa;
}

.nav-tabs .nav-link.active {
    color: var(--primary-color);
    background-color: #fff;
    border-color: var(--border-color) var(--border-color) #fff;
    font-weight: 600;
}

/* 排行榜样式 */
.leaderboard-page {
    max-width: 1000px;
    margin: 0 auto;
}

.leaderboard-header {
    text-align: center;
    margin-bottom: 2rem;
}

.leaderboard-title {
    color: var(--primary-color);
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.leaderboard-subtitle {
    color: #666;
    font-size: 1.1rem;
}

.leaderboard-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    text-align: center;
}

.stat-number {
    font-size: 2rem;
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    color: #666;
    font-size: 0.9rem;
}

.leaderboard-table {
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    overflow: hidden;
}

.leaderboard-list {
    display: flex;
    flex-direction: column;
}

.leaderboard-item {
    display: grid;
    grid-template-columns: 60px 80px 1fr auto 120px;
    align-items: center;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    gap: 1rem;
}

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

.rank-badge {
    font-size: 1.2rem;
    font-weight: bold;
    text-align: center;
}

.rank-1 {
    color: #ffd700;
    font-size: 1.5rem;
}

.rank-2 {
    color: #c0c0c0;
    font-size: 1.4rem;
}

.rank-3 {
    color: #cd7f32;
    font-size: 1.3rem;
}

.user-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: 2px solid var(--border-color);
}

.user-info {
    display: flex;
    flex-direction: column;
}

.user-name {
    font-weight: bold;
    color: var(--text-color);
    font-size: 1.1rem;
}

.user-email {
    color: #666;
    font-size: 0.9rem;
}

.user-score {
    text-align: right;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.score-number {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

.score-label {
    color: #666;
    font-size: 0.85rem;
}

.no-leaderboard {
    text-align: center;
    padding: 3rem;
    color: #666;
    font-size: 1.1rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-menu {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .main-content {
        padding: 1.5rem;
    }
    
    .main-content h1 {
        font-size: 2rem;
    }
    
    .admin-stats {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .leaderboard-item {
        grid-template-columns: 50px 60px 1fr auto;
        gap: 0.5rem;
        padding: 0.75rem;
    }
    
    .user-avatar {
        width: 40px;
        height: 40px;
    }
    
    .user-email {
        display: none;
    }
    
    .quiz-card-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .quiz-header-right {
        align-self: stretch;
        justify-content: space-between;
    }
    
    .user-card {
        flex-direction: column;
        align-items: center;
        text-align: center;
        padding: 1.5rem;
    }
    
    .user-card-avatar {
        margin-right: 0;
        margin-bottom: 1rem;
    }
    
    .user-card-info {
        text-align: center;
        padding-top: 0;
    }
    
    .user-card-logout {
        align-self: center;
        margin-top: 0.5rem;
    }
}