/* ============================================
   小学英语乐园 - 全新布局样式表
   平板优先 · 侧边栏导航 · 清晰视觉层次
   ============================================ */

/* --- 变量 --- */
:root {
    --bg-primary: #F5F0E8;
    --bg-secondary: #FFFFFF;
    --bg-card: #FFFFFF;
    --bg-hover: #EDE8DC;
    --bg-sidebar: #1E293B;
    --bg-sidebar-hover: #334155;
    --bg-sidebar-active: #3B82F6;
    --text-primary: #1E293B;
    --text-secondary: #64748B;
    --text-muted: #94A3B8;
    --text-sidebar: #CBD5E1;
    --text-sidebar-active: #FFFFFF;
    --accent-blue: #3B82F6;
    --accent-red: #EF4444;
    --accent-green: #22C55E;
    --accent-yellow: #EAB308;
    --accent-cyan: #06B6D4;
    --accent-purple: #8B5CF6;
    --accent-orange: #F97316;
    --accent-pink: #EC4899;
    --border-color: #E2E8F0;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.12);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --transition: 0.25s ease;
    --font-english: 'Comic Neue', 'Nunito', sans-serif;
    --font-chinese: -apple-system, 'Microsoft YaHei', 'PingFang SC', sans-serif;
    --sidebar-width: 220px;
    --topbar-height: 52px;
    --bottom-nav-height: 56px;
}

/* --- 暗色主题 --- */
[data-theme="dark"] {
    --bg-primary: #0F172A;
    --bg-secondary: #1E293B;
    --bg-card: #1E293B;
    --bg-hover: #334155;
    --bg-sidebar: #0B1120;
    --bg-sidebar-hover: #1E293B;
    --text-primary: #E2E8F0;
    --text-secondary: #94A3B8;
    --text-muted: #64748B;
    --border-color: #334155;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.5);
}
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --bg-primary: #0F172A;
        --bg-secondary: #1E293B;
        --bg-card: #1E293B;
        --bg-hover: #334155;
        --bg-sidebar: #0B1120;
        --bg-sidebar-hover: #1E293B;
        --text-primary: #E2E8F0;
        --text-secondary: #94A3B8;
        --text-muted: #64748B;
        --border-color: #334155;
        --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
        --shadow-md: 0 4px 12px rgba(0,0,0,0.4);
        --shadow-lg: 0 10px 30px rgba(0,0,0,0.5);
    }
}

/* --- 基础重置 --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
    font-family: var(--font-chinese);
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    transition: background var(--transition), color var(--transition);
    overflow-x: hidden;
}
h1, h2, h3, h4 { font-family: var(--font-chinese); font-weight: 800; }
.hidden { display: none !important; }

/* ============================================
   移动端顶部栏 (仅 <900px 显示)
   ============================================ */
.mobile-topbar {
    display: none;
    position: fixed; top: 0; left: 0; right: 0;
    height: var(--topbar-height);
    background: var(--bg-card);
    border-bottom: 1px solid var(--border-color);
    align-items: center; justify-content: space-between;
    padding: 0 12px; z-index: 900;
    box-shadow: var(--shadow-sm);
}
.topbar-hamburger {
    width: 40px; height: 40px; border: none; background: transparent;
    cursor: pointer; display: flex; flex-direction: column; align-items: center;
    justify-content: center; gap: 5px; border-radius: var(--radius-sm);
    transition: background var(--transition);
}
.topbar-hamburger:hover { background: var(--bg-hover); }
.topbar-hamburger span {
    display: block; width: 20px; height: 2px; background: var(--text-primary);
    border-radius: 1px; transition: all var(--transition);
}
.topbar-title { font-weight: 800; font-size: 1.05rem; color: var(--accent-blue); }
.topbar-theme {
    width: 40px; height: 40px; border: none; background: transparent;
    font-size: 1.2rem; cursor: pointer; border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    transition: background var(--transition);
}
.topbar-theme:hover { background: var(--bg-hover); }

/* 遮罩 */
.mobile-overlay {
    display: none; position: fixed; top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.5); z-index: 998;
    backdrop-filter: blur(2px);
}
.mobile-overlay.show { display: block; }

/* ============================================
   侧边栏导航
   ============================================ */
.sidebar {
    position: fixed; top: 0; left: 0; bottom: 0;
    width: var(--sidebar-width);
    background: var(--bg-sidebar);
    display: flex; flex-direction: column;
    z-index: 1000;
    transition: transform 0.3s ease;
    overflow-y: auto;
}

/* 侧边栏头部 */
.sidebar-header {
    display: flex; align-items: center; gap: 10px;
    padding: 20px 16px 16px; border-bottom: 1px solid rgba(255,255,255,0.08);
}
.sidebar-logo { font-size: 2rem; }
.sidebar-brand { display: flex; flex-direction: column; }
.sidebar-title { font-weight: 800; font-size: 1.1rem; color: #F8FAFC; }
.sidebar-subtitle { font-size: 0.7rem; color: #64748B; margin-top: 1px; }

/* 侧边栏导航项 */
.sidebar-nav {
    flex: 1; padding: 12px 8px; display: flex; flex-direction: column; gap: 2px;
}
.nav-group-label {
    font-size: 0.7rem; font-weight: 700; color: #475569;
    text-transform: uppercase; letter-spacing: 0.05em;
    padding: 16px 12px 6px; user-select: none;
}
.nav-group-label:first-child { padding-top: 4px; }

.nav-link {
    display: flex; align-items: center; gap: 10px;
    padding: 10px 12px; border-radius: var(--radius-sm);
    color: var(--text-sidebar); text-decoration: none;
    font-size: 0.9rem; font-weight: 600; white-space: nowrap;
    transition: all 0.2s ease; cursor: pointer; user-select: none;
}
.nav-link:hover { background: var(--bg-sidebar-hover); color: #F1F5F9; }
.nav-link.active {
    background: var(--bg-sidebar-active); color: var(--text-sidebar-active);
    box-shadow: 0 2px 8px rgba(59,130,246,0.3);
}
.nav-icon { font-size: 1.15rem; width: 24px; text-align: center; flex-shrink: 0; }
.nav-text { flex: 1; }

/* 侧边栏底部 */
.sidebar-footer {
    padding: 12px 8px; border-top: 1px solid rgba(255,255,255,0.08);
}
.theme-toggle {
    display: flex; align-items: center; gap: 10px;
    padding: 10px 12px; border-radius: var(--radius-sm);
    color: #64748B; background: transparent; border: none;
    font-size: 0.85rem; font-weight: 600; font-family: var(--font-chinese);
    cursor: pointer; width: 100%; transition: all 0.2s ease;
}
.theme-toggle:hover { background: var(--bg-sidebar-hover); color: #94A3B8; }
.theme-icon { font-size: 1.1rem; width: 24px; text-align: center; }

/* ============================================
   主内容区域
   ============================================ */
.main-content {
    margin-left: var(--sidebar-width);
    min-height: 100vh;
    transition: margin var(--transition);
}
.page {
    display: none; padding: 28px 0 40px;
    animation: fadeIn 0.3s ease;
}
.page.active { display: block; }
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}
.container { max-width: 1000px; margin: 0 auto; padding: 0 28px; }

/* ============================================
   页面标题
   ============================================ */
.page-header { text-align: center; margin-bottom: 28px; }
.page-header h1 { font-size: 1.7rem; margin-bottom: 6px; }
.page-desc { color: var(--text-secondary); font-size: 0.95rem; }
.section-title { font-size: 1.15rem; font-weight: 800; margin-bottom: 16px; color: var(--text-primary); }
.gradient-text {
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple), var(--accent-pink));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}

/* ============================================
   首页 - Hero 区域
   ============================================ */
.home-hero {
    display: flex; align-items: center; gap: 32px;
    background: linear-gradient(135deg, #1E3A5F 0%, #2563EB 60%, #7C3AED 100%);
    border-radius: var(--radius-xl); padding: 36px 32px;
    margin-bottom: 28px; position: relative; overflow: hidden;
}
.home-hero::before {
    content: ''; position: absolute; top: -30%; right: -10%;
    width: 300px; height: 300px;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    border-radius: 50%;
}
.hero-text { flex: 1; position: relative; z-index: 1; }
.hero-title { font-size: 1.8rem; margin-bottom: 8px; color: #FFFFFF; }
.hero-title .gradient-text {
    background: linear-gradient(135deg, #FDE68A, #FCA5A5, #C4B5FD);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.hero-subtitle { font-size: 0.95rem; color: rgba(255,255,255,0.75); line-height: 1.6; }

.hero-cta {
    display: flex; align-items: center; gap: 14px;
    padding: 16px 28px; border-radius: var(--radius-lg);
    background: rgba(255,255,255,0.15); border: 2px solid rgba(255,255,255,0.3);
    color: #FFFFFF; cursor: pointer; font-family: var(--font-chinese);
    transition: all 0.3s ease; position: relative; z-index: 1;
    backdrop-filter: blur(8px); flex-shrink: 0;
}
.hero-cta:hover {
    background: rgba(255,255,255,0.25); border-color: rgba(255,255,255,0.5);
    transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,0.2);
}
.cta-icon { font-size: 2rem; }
.cta-text { display: flex; flex-direction: column; text-align: left; }
.cta-main { font-size: 1.1rem; font-weight: 800; }
.cta-sub { font-size: 0.75rem; opacity: 0.8; margin-top: 2px; }

/* ============================================
   首页 - 统计数据
   ============================================ */
.home-stats {
    display: grid; grid-template-columns: repeat(4, 1fr);
    gap: 14px; margin-bottom: 32px;
}
.stat-card {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 18px 16px; display: flex; align-items: center; gap: 14px;
    box-shadow: var(--shadow-sm); transition: all var(--transition);
    border: 1px solid var(--border-color);
}
.stat-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.stat-icon-wrap {
    width: 44px; height: 44px; border-radius: var(--radius-md);
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
}
.stat-blue { background: #DBEAFE; }
.stat-green { background: #DCFCE7; }
.stat-orange { background: #FFF7ED; }
.stat-purple { background: #F3E8FF; }
[data-theme="dark"] .stat-blue { background: #1E3A5F; }
[data-theme="dark"] .stat-green { background: #14532D; }
[data-theme="dark"] .stat-orange { background: #431407; }
[data-theme="dark"] .stat-purple { background: #3B0764; }
.stat-icon { font-size: 1.3rem; }
.stat-info { display: flex; flex-direction: column; min-width: 0; }
.stat-number { font-size: 1.5rem; font-weight: 800; font-family: var(--font-english); line-height: 1.2; }
.stat-card:nth-child(1) .stat-number { color: var(--accent-blue); }
.stat-card:nth-child(2) .stat-number { color: var(--accent-green); }
.stat-card:nth-child(3) .stat-number { color: var(--accent-orange); }
.stat-card:nth-child(4) .stat-number { color: var(--accent-purple); }
.stat-label { font-size: 0.78rem; color: var(--text-secondary); font-weight: 600; }

/* ============================================
   首页 - 功能入口卡片
   ============================================ */
.shortcut-grid {
    display: grid; grid-template-columns: repeat(3, 1fr);
    gap: 14px;
}
.shortcut-card {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 20px 18px; display: flex; align-items: center; gap: 14px;
    box-shadow: var(--shadow-sm); cursor: pointer;
    transition: all var(--transition);
    border: 1px solid var(--border-color);
}
.shortcut-card:hover {
    transform: translateY(-3px); box-shadow: var(--shadow-md);
    border-color: var(--accent-blue);
}
.shortcut-icon {
    width: 48px; height: 48px; border-radius: var(--radius-md);
    display: flex; align-items: center; justify-content: center;
    font-size: 1.4rem; flex-shrink: 0;
}
.sc-blue { background: #DBEAFE; }
.sc-green { background: #DCFCE7; }
.sc-orange { background: #FFF7ED; }
.sc-pink { background: #FCE7F3; }
.sc-red { background: #FEE2E2; }
.sc-purple { background: #F3E8FF; }
[data-theme="dark"] .sc-blue { background: #1E3A5F; }
[data-theme="dark"] .sc-green { background: #14532D; }
[data-theme="dark"] .sc-orange { background: #431407; }
[data-theme="dark"] .sc-pink { background: #4A0D2B; }
[data-theme="dark"] .sc-red { background: #450A0A; }
[data-theme="dark"] .sc-purple { background: #3B0764; }
.shortcut-body { flex: 1; min-width: 0; }
.shortcut-title { font-size: 0.95rem; font-weight: 700; margin-bottom: 3px; }
.shortcut-desc { font-size: 0.78rem; color: var(--text-secondary); line-height: 1.4; }
.shortcut-arrow {
    font-size: 1.2rem; color: var(--text-muted); flex-shrink: 0;
    transition: transform var(--transition), color var(--transition);
}
.shortcut-card:hover .shortcut-arrow { transform: translateX(4px); color: var(--accent-blue); }

/* ============================================
   面包屑导航
   ============================================ */
.breadcrumb {
    display: flex; align-items: center; gap: 6px;
    margin-bottom: 20px; flex-wrap: wrap;
    padding: 10px 14px; background: var(--bg-card);
    border-radius: var(--radius-md); border: 1px solid var(--border-color);
    font-size: 0.85rem;
}
.breadcrumb-item {
    color: var(--text-secondary); cursor: pointer; font-weight: 600;
    transition: color var(--transition); padding: 2px 6px;
    border-radius: 4px;
}
.breadcrumb-item:hover { color: var(--accent-blue); background: var(--bg-hover); }
.breadcrumb-item.active { color: var(--accent-blue); cursor: default; }
.breadcrumb-item.active:hover { background: transparent; }
.breadcrumb-sep { color: var(--text-muted); font-size: 0.75rem; user-select: none; }

/* ============================================
   按钮
   ============================================ */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 6px;
    padding: 10px 20px; border-radius: var(--radius-md);
    font-size: 0.9rem; font-weight: 700; font-family: var(--font-chinese);
    cursor: pointer; border: 2px solid transparent;
    transition: all var(--transition); user-select: none; min-height: 44px;
}
.btn-primary { background: var(--accent-blue); color: #fff; border-color: var(--accent-blue); }
.btn-primary:hover { background: #2563EB; transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-outline { background: transparent; color: var(--accent-blue); border-color: var(--accent-blue); }
.btn-outline:hover { background: var(--accent-blue); color: #fff; transform: translateY(-1px); }
.btn-sm { padding: 6px 14px; font-size: 0.82rem; min-height: 36px; }
.btn-nav { background: var(--bg-card); color: var(--text-primary); border: 2px solid var(--border-color); font-size: 0.88rem; }
.btn-nav:hover { border-color: var(--accent-blue); color: var(--accent-blue); }
.btn-star { font-size: 1.3rem; width: 52px; color: var(--accent-yellow); }
.btn-star.starred { color: var(--accent-yellow); }

/* ============================================
   Tab 和模式选择器
   ============================================ */
.tab, .mode-btn {
    padding: 9px 18px; border-radius: var(--radius-sm);
    border: 2px solid var(--border-color); background: var(--bg-card);
    color: var(--text-secondary); font-size: 0.9rem; font-weight: 700;
    font-family: var(--font-chinese); cursor: pointer;
    transition: all var(--transition);
}
.tab:hover, .mode-btn:hover { border-color: var(--accent-blue); color: var(--accent-blue); }
.tab.active, .mode-btn.active { background: var(--accent-blue); color: #fff; border-color: var(--accent-blue); }

/* ============================================
   单词学习 - 书本网格卡片（v2 游戏化布局）
   ============================================ */
.book-card-v2 {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 18px 20px; cursor: pointer;
    transition: all 0.3s ease; border: 2px solid var(--border-color);
    position: relative; overflow: hidden;
}
.book-card-v2::before {
    content: ''; position: absolute; top: 0; left: 0;
    width: 4px; height: 100%; background: var(--book-color, var(--accent-blue));
    border-radius: 4px 0 0 4px; transition: width 0.3s ease;
}
.book-card-v2:hover {
    transform: translateY(-3px); box-shadow: var(--shadow-md);
    border-color: var(--book-color, var(--accent-blue));
}
.book-card-v2:hover::before { width: 6px; }
.book-card-v2.active {
    border-color: var(--book-color, var(--accent-blue));
    background: color-mix(in srgb, var(--book-color, var(--accent-blue)) 6%, var(--bg-card));
    box-shadow: var(--shadow-md);
}

.book-card-top {
    display: flex; align-items: center; gap: 12px; margin-bottom: 12px;
}
.book-card-icon {
    font-size: 1.8rem; width: 44px; height: 44px;
    display: flex; align-items: center; justify-content: center;
    background: color-mix(in srgb, var(--book-color, var(--accent-blue)) 12%, transparent);
    border-radius: var(--radius-md); flex-shrink: 0;
}
.book-card-info { flex: 1; min-width: 0; }
.book-card-label { font-size: 1rem; font-weight: 700; color: var(--text-primary); }
.book-card-semester { font-size: 0.78rem; color: var(--text-secondary); margin-top: 2px; }
.book-card-arrow {
    font-size: 1.3rem; color: var(--text-muted); flex-shrink: 0;
    transition: transform 0.3s ease, color 0.3s ease;
}
.book-card-v2:hover .book-card-arrow { transform: translateX(4px); color: var(--book-color, var(--accent-blue)); }

.book-card-progress { display: flex; align-items: center; gap: 10px; }
.book-progress-bar {
    flex: 1; height: 6px; background: var(--border-color);
    border-radius: 3px; overflow: hidden;
}
.book-progress-fill {
    height: 100%; border-radius: 3px; transition: width 0.5s ease;
    background: var(--book-color, var(--accent-blue));
}
.book-progress-text {
    font-size: 0.75rem; font-weight: 700; color: var(--text-muted);
    white-space: nowrap; min-width: 40px; text-align: right;
}

/* 书本网格容器 - 使用 grid */
.grade-selector {
    display: grid !important; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 14px; margin-bottom: 20px;
}

/* ============================================
   单词学习 - 单元卡片（v2）
   ============================================ */
.unit-card-v2 {
    display: flex; align-items: center; gap: 14px;
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 16px 18px; cursor: pointer;
    transition: all 0.3s ease; border: 2px solid var(--border-color);
    position: relative; overflow: hidden;
}
.unit-card-v2::after {
    content: ''; position: absolute; right: 16px; top: 50%;
    transform: translateY(-50%); font-size: 1.2rem; color: var(--text-muted);
    transition: transform 0.3s ease;
}
.unit-card-v2:hover {
    transform: translateY(-2px); box-shadow: var(--shadow-md);
    border-color: var(--unit-color, var(--accent-blue));
}
.unit-card-v2:hover::after { transform: translateY(-50%) translateX(4px); }

.unit-card-number {
    width: 40px; height: 40px; border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 1rem; font-weight: 800; color: #FFFFFF;
    background: var(--unit-color, var(--accent-blue)); flex-shrink: 0;
    font-family: var(--font-english);
}
.unit-card-body { flex: 1; min-width: 0; }
.unit-card-title { font-size: 0.95rem; font-weight: 700; color: var(--text-primary); margin-bottom: 2px; }
.unit-card-module { font-size: 0.78rem; color: var(--text-secondary); margin-bottom: 6px; }
.unit-card-meta {
    display: flex; align-items: center; gap: 10px;
    font-size: 0.78rem; color: var(--text-muted); margin-bottom: 6px;
}
.unit-card-bar {
    height: 4px; background: var(--border-color);
    border-radius: 2px; overflow: hidden;
}
.unit-card-fill {
    height: 100%; border-radius: 2px; transition: width 0.5s ease;
    background: var(--unit-color, var(--accent-blue));
}

/* 单元状态标签 */
.unit-done { color: var(--accent-green); font-weight: 700; }
.unit-progress { color: var(--accent-blue); font-weight: 700; }
.unit-new { color: var(--text-muted); font-weight: 600; }

/* 单元列表容器 */
#unitList {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 12px;
}

/* ============================================
   音标 - 双播放按钮（音标发音 + 单词发音）
   ============================================ */
.phonetic-card-actions {
    display: flex; gap: 6px; justify-content: center; margin-top: 8px;
}
.phonetic-btn {
    width: 32px; height: 32px; border-radius: 50%;
    border: 1.5px solid var(--border-color); background: var(--bg-primary);
    cursor: pointer; font-size: 0.85rem;
    display: flex; align-items: center; justify-content: center;
    transition: all 0.2s ease;
}
.phonetic-btn:hover { background: var(--accent-cyan); color: #fff; border-color: var(--accent-cyan); transform: scale(1.1); }
.phonetic-btn.phoneme-play { border-color: var(--accent-cyan); }
.phonetic-btn.word-play { border-color: var(--accent-blue); }

/* ============================================
   年级/册别/单元选择
   ============================================ */
.book-selector {
    display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 20px; justify-content: center;
}
.grade-card, .book-card, .unit-card {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 20px 16px; text-align: center; box-shadow: var(--shadow-sm);
    cursor: pointer; transition: all var(--transition);
    border: 2px solid var(--border-color); min-width: 120px; flex: 1; max-width: 170px;
}
.grade-card:hover, .book-card:hover, .unit-card:hover {
    transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--accent-blue);
}
.grade-card.active, .book-card.active, .unit-card.active {
    border-color: var(--accent-blue); background: #EFF6FF;
}
[data-theme="dark"] .grade-card.active,
[data-theme="dark"] .book-card.active,
[data-theme="dark"] .unit-card.active { background: #1E3A5F; }
.grade-icon { font-size: 2rem; margin-bottom: 8px; }
.grade-label { font-size: 1rem; font-weight: 700; }
.grade-sub { font-size: 0.8rem; color: var(--text-secondary); margin-top: 4px; }
.unit-list {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 14px; margin-bottom: 24px;
}

/* ============================================
   学习工具栏
   ============================================ */
.study-toolbar {
    display: flex; align-items: center; gap: 12px; margin-bottom: 24px; flex-wrap: wrap;
}
.study-progress {
    display: flex; align-items: center; gap: 8px; margin-left: auto;
    font-size: 0.88rem; color: var(--text-secondary); font-weight: 600;
}
.progress-bar {
    width: 120px; height: 8px; background: var(--border-color);
    border-radius: 4px; overflow: hidden;
}
.progress-fill {
    height: 100%; background: linear-gradient(90deg, var(--accent-blue), var(--accent-green));
    border-radius: 4px; transition: width 0.4s ease; width: 0%;
}

/* ============================================
   闪卡
   ============================================ */
.flashcard-area { display: flex; flex-direction: column; align-items: center; gap: 20px; }
.flashcard { width: 380px; height: 270px; perspective: 1000px; cursor: pointer; }
.flashcard-inner {
    position: relative; width: 100%; height: 100%;
    transition: transform 0.6s; transform-style: preserve-3d;
}
.flashcard.flipped .flashcard-inner { transform: rotateY(180deg); }
.flashcard-front, .flashcard-back {
    position: absolute; width: 100%; height: 100%;
    backface-visibility: hidden; border-radius: var(--radius-xl);
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    padding: 32px; box-shadow: var(--shadow-md);
}
.flashcard-front {
    background: linear-gradient(145deg, var(--bg-card), #EFF6FF);
    border: 2px solid var(--accent-blue);
}
.flashcard-back {
    background: linear-gradient(145deg, #F0FDF4, var(--bg-card));
    border: 2px solid var(--accent-green); transform: rotateY(180deg);
}
.card-word {
    font-family: var(--font-english); font-size: 2.4rem;
    font-weight: 800; color: var(--accent-blue); margin-bottom: 8px;
}
.card-phonetic {
    font-family: 'Courier New', monospace; font-size: 1.05rem;
    color: var(--text-secondary); margin-bottom: 16px;
}
.card-hint { font-size: 0.78rem; color: var(--text-muted); margin-top: 12px; }
.card-pos {
    font-size: 0.88rem; color: var(--accent-purple);
    font-weight: 600; margin-bottom: 12px; font-style: italic;
}
.card-meaning { font-size: 1.5rem; font-weight: 700; color: var(--accent-green); margin-bottom: 16px; }
.card-example { font-size: 0.92rem; color: var(--text-secondary); text-align: center; line-height: 1.6; }
.card-example .en { font-family: var(--font-english); font-weight: 600; display: block; margin-bottom: 4px; }
.card-example .cn { font-size: 0.82rem; }
.btn-speak {
    width: 44px; height: 44px; border-radius: 50%;
    border: 2px solid var(--accent-blue); background: var(--bg-card);
    font-size: 1.3rem; cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    transition: all var(--transition); margin-top: 12px;
}
.btn-speak:hover { background: var(--accent-blue); transform: scale(1.1); }
.flashcard-nav { display: flex; align-items: center; gap: 16px; }

/* ============================================
   单词列表
   ============================================ */
.word-search { margin-bottom: 16px; }
.search-input {
    width: 100%; padding: 12px 16px; border-radius: var(--radius-md);
    border: 2px solid var(--border-color); background: var(--bg-card);
    color: var(--text-primary); font-size: 0.95rem; font-family: var(--font-chinese);
    transition: border-color var(--transition);
}
.search-input:focus { outline: none; border-color: var(--accent-blue); }
.word-table { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 10px; }
.word-item {
    display: flex; align-items: center; gap: 12px;
    background: var(--bg-card); border-radius: var(--radius-md);
    padding: 14px 16px; box-shadow: var(--shadow-sm);
    transition: all var(--transition); border: 1px solid var(--border-color);
}
.word-item:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); border-color: var(--accent-blue); }
.word-item-left { flex: 1; min-width: 0; }
.word-text { font-family: var(--font-english); font-size: 1.1rem; font-weight: 700; color: var(--accent-blue); }
.word-phonetic-sm { font-family: 'Courier New', monospace; font-size: 0.78rem; color: var(--text-muted); }
.word-meaning-sm { font-size: 0.85rem; color: var(--text-secondary); margin-top: 2px; }
.word-item-actions { display: flex; gap: 6px; margin-left: auto; flex-shrink: 0; }
.word-item-actions button {
    width: 36px; height: 36px; border-radius: 50%;
    border: 1px solid var(--border-color); background: var(--bg-primary);
    cursor: pointer; font-size: 1rem;
    display: flex; align-items: center; justify-content: center;
    transition: all var(--transition);
}
.word-item-actions button:hover { background: var(--accent-blue); color: #fff; border-color: var(--accent-blue); }

/* ============================================
   音标
   ============================================ */
.phonetic-tabs, .grammar-grade-tabs, .progress-tabs,
.sentence-mode-selector, .quiz-options {
    display: flex; gap: 10px; margin-bottom: 24px; flex-wrap: wrap; justify-content: center;
}
.phonetic-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px; }
.phonetic-card {
    background: var(--bg-card); border-radius: var(--radius-md);
    padding: 16px; text-align: center; box-shadow: var(--shadow-sm);
    cursor: pointer; transition: all var(--transition);
    border: 2px solid transparent;
}
.phonetic-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--accent-cyan); }
.phonetic-symbol {
    font-family: 'Courier New', monospace; font-size: 1.8rem;
    font-weight: 700; color: var(--accent-cyan); margin-bottom: 4px;
}
.phonetic-example { font-family: var(--font-english); font-size: 0.85rem; color: var(--text-secondary); }
.phonetic-desc { font-size: 0.78rem; color: var(--text-muted); margin-top: 3px; }

/* ============================================
   语法
   ============================================ */
.grammar-content { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 14px; }
.grammar-card {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 20px; box-shadow: var(--shadow-sm);
    border: 2px solid transparent; transition: all var(--transition); cursor: pointer;
}
.grammar-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--accent-purple); }
.grammar-card-title { font-size: 1.05rem; font-weight: 700; color: var(--accent-purple); margin-bottom: 8px; }
.grammar-card-desc { font-size: 0.88rem; color: var(--text-secondary); line-height: 1.6; }

/* --- 语法详情 - 三栏布局 --- */
.grammar-detail { max-width: 100%; }

/* 详情模式下自动撑宽容器 */
body.grammar-detail-active #page-grammar > .container {
    max-width: 1400px;
    transition: max-width 0.3s ease;
}

.grammar-detail-header {
    display: flex; align-items: center; gap: 16px; margin-bottom: 20px;
}
.grammar-detail-title {
    font-size: 1.3rem; font-weight: 800; color: var(--accent-purple); margin: 0;
}

.grammar-three-cols {
    display: grid;
    grid-template-columns: minmax(200px, auto) minmax(240px, 1.3fr) minmax(260px, 1.3fr);
    gap: 16px;
    align-items: start;
}

/* 三栏面板公共样式 */
.grammar-col-explain,
.grammar-col-formula,
.grammar-col-exercise {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 22px 20px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.grammar-col-title {
    font-size: 0.95rem; font-weight: 800; color: var(--text-primary);
    margin-bottom: 16px; display: flex; align-items: center; gap: 8px;
    padding-bottom: 12px; border-bottom: 2px solid var(--border-color);
}
.grammar-col-icon { font-size: 1.1rem; }

/* 左栏：语法讲解 */
.grammar-explain-text {
    font-size: 0.92rem; color: var(--text-secondary); line-height: 1.9;
}
.grammar-category-tag {
    display: inline-block; margin-top: 16px;
    padding: 4px 12px; border-radius: 20px;
    font-size: 0.75rem; font-weight: 700;
    background: color-mix(in srgb, var(--accent-purple) 12%, transparent);
    color: var(--accent-purple);
}

/* 中栏：公式与例句 */
.grammar-formula-list { display: flex; flex-direction: column; gap: 12px; }
.grammar-formula {
    background: var(--bg-primary); border-radius: var(--radius-sm);
    padding: 14px 16px; border-left: 3px solid var(--accent-blue);
}
.formula-pattern { font-weight: 700; color: var(--accent-blue); font-size: 0.92rem; font-family: var(--font-english); }
.formula-example { margin-top: 6px; font-size: 0.9rem; color: var(--text-primary); font-family: var(--font-english); font-weight: 600; }
.formula-example-cn { margin-top: 3px; font-size: 0.82rem; color: var(--text-secondary); }

/* 右栏：练习题 */
.grammar-exercise-list { display: flex; flex-direction: column; gap: 18px; }
.grammar-exercise { }
.grammar-exercise .exercise-question { font-size: 0.9rem; font-weight: 600; margin-bottom: 10px; line-height: 1.5; }
.grammar-exercise .exercise-option {
    padding: 8px 14px; border-radius: var(--radius-sm);
    border: 2px solid var(--border-color); background: var(--bg-primary);
    cursor: pointer; transition: all var(--transition);
    font-size: 0.88rem; font-family: var(--font-chinese); margin-bottom: 5px;
}
.grammar-exercise .exercise-option:hover { border-color: var(--accent-blue); }
.grammar-exercise .exercise-option.correct { border-color: var(--accent-green); background: #DCFCE7; }
.grammar-exercise .exercise-option.wrong { border-color: var(--accent-red); background: #FEE2E2; }
.grammar-formula {
    background: var(--bg-primary); border-radius: var(--radius-sm);
    padding: 12px 16px; margin: 12px 0; font-family: var(--font-english);
    font-size: 0.92rem; border-left: 3px solid var(--accent-blue);
}
.exercise-question { font-size: 0.95rem; font-weight: 600; margin-bottom: 12px; }
.exercise-option {
    padding: 10px 16px; border-radius: var(--radius-sm);
    border: 2px solid var(--border-color); background: var(--bg-primary);
    cursor: pointer; transition: all var(--transition);
    font-size: 0.92rem; font-family: var(--font-chinese); margin-bottom: 6px;
}
.exercise-option:hover { border-color: var(--accent-blue); }
.exercise-option.correct { border-color: var(--accent-green); background: #DCFCE7; }
.exercise-option.wrong { border-color: var(--accent-red); background: #FEE2E2; }
.exercise-feedback { margin-top: 12px; padding: 10px 16px; border-radius: var(--radius-sm); font-size: 0.88rem; font-weight: 600; }
.exercise-feedback.correct { background: #DCFCE7; color: #166534; }
.exercise-feedback.wrong { background: #FEE2E2; color: #991B1B; }

/* ============================================
   造句
   ============================================ */
.sentence-area { max-width: 700px; margin: 0 auto; }
.sentence-prompt {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 24px; margin-bottom: 20px; box-shadow: var(--shadow-sm); text-align: center;
    border: 1px solid var(--border-color);
}
.prompt-label { font-size: 0.85rem; color: var(--text-muted); margin-bottom: 8px; }
.prompt-text { font-size: 1.15rem; font-weight: 700; }
.word-bank { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 20px; justify-content: center; }
.word-chip {
    padding: 8px 16px; border-radius: 20px;
    background: var(--accent-blue); color: #fff;
    font-weight: 700; font-family: var(--font-english);
    cursor: pointer; transition: all var(--transition); user-select: none;
}
.word-chip:hover { transform: scale(1.05); }
.word-chip.used { opacity: 0.3; pointer-events: none; }
.sentence-drop-zone {
    min-height: 60px; border: 2px dashed var(--border-color);
    border-radius: var(--radius-md); padding: 16px;
    display: flex; gap: 8px; flex-wrap: wrap; align-items: center; justify-content: center;
    margin-bottom: 20px; transition: all var(--transition);
}
.sentence-result {
    text-align: center; padding: 16px; border-radius: var(--radius-md);
    font-size: 1.05rem; font-weight: 700; margin-bottom: 16px;
}
.sentence-result.correct { background: #DCFCE7; color: var(--accent-green); }
.sentence-result.wrong { background: #FEE2E2; color: var(--accent-red); }

/* ============================================
   测试
   ============================================ */
.quiz-option-card {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 24px 16px; text-align: center; box-shadow: var(--shadow-sm);
    cursor: pointer; transition: all var(--transition);
    border: 2px solid var(--border-color); flex: 1; min-width: 160px; max-width: 220px;
}
.quiz-option-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--accent-blue); }
.quiz-option-icon { font-size: 2rem; margin-bottom: 8px; }
.quiz-option-title { font-size: 1rem; font-weight: 700; margin-bottom: 4px; }
.quiz-option-desc { font-size: 0.78rem; color: var(--text-secondary); }
.quiz-header {
    display: flex; align-items: center; gap: 12px; margin-bottom: 24px; flex-wrap: wrap;
}
.quiz-progress-text { font-weight: 700; font-size: 0.92rem; color: var(--text-secondary); white-space: nowrap; }
.quiz-score { font-weight: 700; color: var(--accent-blue); white-space: nowrap; margin-left: auto; }
.quiz-question-area {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 28px 24px; box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}
.quiz-question-type {
    font-size: 0.78rem; color: var(--accent-blue); font-weight: 700;
    margin-bottom: 8px; text-transform: uppercase;
}
.quiz-question-text { font-size: 1.1rem; font-weight: 700; margin-bottom: 20px; line-height: 1.6; }
.quiz-options-list { display: flex; flex-direction: column; gap: 10px; }
.quiz-option-btn {
    padding: 14px 18px; border-radius: var(--radius-md);
    border: 2px solid var(--border-color); background: var(--bg-primary);
    cursor: pointer; transition: all var(--transition);
    font-size: 0.95rem; font-family: var(--font-chinese); text-align: left;
}
.quiz-option-btn:hover { border-color: var(--accent-blue); background: var(--bg-hover); }
.quiz-option-btn.correct { border-color: var(--accent-green); background: #DCFCE7; }
.quiz-option-btn.wrong { border-color: var(--accent-red); background: #FEE2E2; }
.quiz-feedback { margin-top: 16px; padding: 14px 18px; border-radius: var(--radius-md); font-size: 0.92rem; font-weight: 600; }
.quiz-feedback.correct-feedback { background: #DCFCE7; color: #166534; }
.quiz-feedback.wrong-feedback { background: #FEE2E2; color: #991B1B; }

/* ============================================
   测试结果
   ============================================ */
.result-card {
    background: var(--bg-card); border-radius: var(--radius-xl);
    padding: 40px 24px; text-align: center; box-shadow: var(--shadow-md);
    max-width: 500px; margin: 0 auto; border: 1px solid var(--border-color);
}
.result-card h2 { font-size: 1.7rem; margin-bottom: 20px; }
.result-score { font-size: 2.8rem; font-weight: 800; font-family: var(--font-english); color: var(--accent-blue); margin-bottom: 8px; }
.result-accuracy { font-size: 1.4rem; font-weight: 700; color: var(--accent-green); margin-bottom: 20px; }
.result-details { font-size: 0.92rem; color: var(--text-secondary); margin-bottom: 24px; line-height: 1.8; }
.result-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

/* ============================================
   进度页
   ============================================ */
.progress-content { max-width: 800px; margin: 0 auto; }
.progress-overview-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 14px; margin-bottom: 28px;
}
.progress-grade-card {
    background: var(--bg-card); border-radius: var(--radius-md);
    padding: 16px; box-shadow: var(--shadow-sm); border: 2px solid var(--border-color);
}
.progress-grade-title { font-size: 0.95rem; font-weight: 700; margin-bottom: 8px; }
.progress-grade-bar { height: 8px; background: var(--border-color); border-radius: 4px; overflow: hidden; margin-bottom: 6px; }
.progress-grade-fill { height: 100%; border-radius: 4px; transition: width 0.6s ease; }
.progress-grade-text { font-size: 0.78rem; color: var(--text-secondary); }
.wrong-list, .fav-list { display: flex; flex-direction: column; gap: 10px; }
.wrong-item, .fav-item {
    display: flex; align-items: center; gap: 12px;
    background: var(--bg-card); border-radius: var(--radius-md);
    padding: 14px 16px; box-shadow: var(--shadow-sm); border: 1px solid var(--border-color);
}
.wrong-item-info, .fav-item-info { flex: 1; min-width: 0; }
.wrong-item-word { font-family: var(--font-english); font-weight: 700; color: var(--accent-blue); font-size: 1rem; }
.wrong-item-answer { font-size: 0.82rem; color: var(--accent-red); }

/* ============================================
   日历
   ============================================ */
.calendar-grid { display: grid; grid-template-columns: repeat(7, 1fr); gap: 4px; margin-bottom: 16px; }
.calendar-day {
    aspect-ratio: 1; border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    font-size: 0.78rem; font-weight: 600; background: var(--bg-primary);
    transition: all var(--transition);
}
.calendar-day.has-activity-1 { background: #BBF7D0; }
.calendar-day.has-activity-2 { background: #4ADE80; color: #fff; }
.calendar-day.has-activity-3 { background: #16A34A; color: #fff; }
.calendar-day.today { border: 2px solid var(--accent-blue); }
[data-theme="dark"] .calendar-day.has-activity-1 { background: #14532D; }
[data-theme="dark"] .calendar-day.has-activity-2 { background: #166534; }
[data-theme="dark"] .calendar-day.has-activity-3 { background: #15803D; }
.calendar-header { display: grid; grid-template-columns: repeat(7, 1fr); gap: 4px; margin-bottom: 4px; }
.calendar-header span { text-align: center; font-size: 0.72rem; font-weight: 700; color: var(--text-muted); }

/* ============================================
   模态框
   ============================================ */
.modal-overlay {
    position: fixed; top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.5); z-index: 2000;
    display: flex; align-items: center; justify-content: center;
    padding: 20px; animation: fadeIn 0.2s ease;
    backdrop-filter: blur(3px);
}
.modal-overlay.hidden { display: none !important; }
.modal-content {
    background: var(--bg-card); border-radius: var(--radius-xl);
    padding: 32px 24px; max-width: 600px; width: 100%;
    max-height: 80vh; overflow-y: auto;
    box-shadow: var(--shadow-lg); animation: slideUp 0.3s ease;
}
@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ============================================
   Toast 提示
   ============================================ */
.toast-container {
    position: fixed; top: 20px; right: 20px; z-index: 3000;
    display: flex; flex-direction: column; gap: 8px;
}
.toast {
    padding: 12px 20px; border-radius: var(--radius-md);
    font-size: 0.88rem; font-weight: 600; box-shadow: var(--shadow-md);
    animation: slideInRight 0.3s ease, fadeOut 0.3s ease 2.5s forwards;
    max-width: 320px;
}
.toast-success { background: #DCFCE7; color: #166534; border: 1px solid #22C55E; }
.toast-error { background: #FEE2E2; color: #991B1B; border: 1px solid #EF4444; }
.toast-info { background: #DBEAFE; color: #1E40AF; border: 1px solid #3B82F6; }
@keyframes slideInRight { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
@keyframes fadeOut { from { opacity: 1; } to { opacity: 0; transform: translateX(30px); } }

/* ============================================
   底部导航 (仅 <900px 显示)
   ============================================ */
.bottom-nav {
    display: none; position: fixed; bottom: 0; left: 0; right: 0;
    height: var(--bottom-nav-height);
    background: var(--bg-card); border-top: 1px solid var(--border-color);
    z-index: 900; box-shadow: 0 -2px 8px rgba(0,0,0,0.06);
}
.bottom-link {
    display: flex; flex-direction: column; align-items: center;
    justify-content: center; gap: 2px; flex: 1;
    text-decoration: none; color: var(--text-muted);
    font-size: 0.68rem; font-weight: 600; padding: 6px 0;
    transition: all var(--transition); cursor: pointer;
}
.bottom-link span:first-child { font-size: 1.2rem; }
.bottom-link.active { color: var(--accent-blue); }
.bottom-link:hover { color: var(--accent-blue); }

/* ============================================
   工具类
   ============================================ */
.text-center { text-align: center; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }

/* ============================================
   响应式 - 平板竖屏 & 手机 (< 900px)
   ============================================ */
@media (max-width: 900px) {
    /* 显示移动端顶栏和底部导航 */
    .mobile-topbar { display: flex; }
    .bottom-nav { display: flex; }

    /* 侧边栏默认隐藏，可通过汉堡按钮滑入 */
    .sidebar {
        transform: translateX(-100%);
        width: 260px;
        z-index: 1000;
    }
    .sidebar.mobile-open {
        transform: translateX(0);
        box-shadow: 4px 0 24px rgba(0,0,0,0.3);
    }

    /* 主内容去掉侧边栏偏移，加上顶栏和底部导航偏移 */
    .main-content {
        margin-left: 0;
        margin-top: var(--topbar-height);
        margin-bottom: calc(var(--bottom-nav-height) + 8px);
        min-height: calc(100vh - var(--topbar-height));
    }

    .container { padding: 0 16px; }

    /* 首页 Hero */
    .home-hero { flex-direction: column; gap: 20px; padding: 28px 20px; }
    .hero-title { font-size: 1.5rem; }
    .hero-subtitle { font-size: 0.88rem; }
    .hero-cta { width: 100%; justify-content: center; }

    /* 统计卡片 2x2 */
    .home-stats { grid-template-columns: repeat(2, 1fr); gap: 10px; }
    .stat-card { padding: 14px 12px; }
    .stat-number { font-size: 1.3rem; }

    /* 功能入口 2列 */
    .shortcut-grid { grid-template-columns: repeat(2, 1fr); gap: 10px; }
    .shortcut-card { padding: 16px 14px; }
    .shortcut-arrow { display: none; }

    /* 闪卡 */
    .flashcard { width: 320px; height: 240px; }
    .card-word { font-size: 2rem; }

    /* 单词列表 */
    .word-table { grid-template-columns: 1fr; }

    /* 音标网格 */
    .phonetic-grid { grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); }

    /* 书本网格 2列 */
    .grade-selector { grid-template-columns: repeat(2, 1fr) !important; gap: 10px; }

    /* 单元列表单列 */
    #unitList { grid-template-columns: 1fr; }

    /* 语法卡片 */
    .grammar-content { grid-template-columns: 1fr; }

    /* 语法三栏 → 单列堆叠 */
    .grammar-three-cols { grid-template-columns: 1fr; gap: 14px; }
    .grammar-detail-header { flex-wrap: wrap; gap: 10px; }

    /* 测试选项卡 */
    .quiz-options { flex-direction: column; align-items: center; }
    .quiz-option-card { max-width: 100%; }

    /* 页面标题 */
    .page-header h1 { font-size: 1.35rem; }
    .page { padding: 20px 0 32px; }
}

/* ============================================
   响应式 - 小手机 (< 480px)
   ============================================ */
@media (max-width: 480px) {
    .home-stats { grid-template-columns: 1fr 1fr; gap: 8px; }
    .shortcut-grid { grid-template-columns: 1fr; gap: 8px; }
    .shortcut-card { gap: 10px; padding: 14px; }
    .flashcard { width: 280px; height: 220px; }
    .card-word { font-size: 1.7rem; }
    .container { padding: 0 12px; }
    .hero-title { font-size: 1.3rem; }
    .stat-icon-wrap { width: 38px; height: 38px; }
    .stat-icon { font-size: 1.1rem; }

    /* 书本网格单列 */
    .grade-selector { grid-template-columns: 1fr !important; }
    .book-card-v2 { padding: 14px 16px; }
    .unit-card-v2 { padding: 12px 14px; }
}