/* ============================================================
   身体说明书 — 全局样式
   主色调：翠绿 (#059669) —— 健康/活力/免费
   区别于四门课色系（蓝/青/红/紫）
   ============================================================ */

/* ===== 基础重置 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --primary:       #059669;
    --primary-light: #d1fae5;
    --primary-dark:  #047857;
    --accent:        #0ea5e9;
    --accent-light:  #e0f2fe;
    --warning:       #d97706;
    --warning-light: #fef3c7;
    --danger:        #dc2626;
    --danger-light:  #fee2e2;
    --purple:        #7c3aed;
    --purple-light:  #ede9fe;
    --teal:          #0f766e;
    --teal-light:    #ccfbf1;
    --cyan:          #0891b2;
    --cyan-light:    #e0f2fe;
    --rose:          #e11d48;
    --rose-light:    #ffe4e6;
    --gray-50:  #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --radius:    12px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --shadow:    0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
    --transition: all 0.2s ease;
    --heading-color: #111827;
    --text-main: #374151;
    --text-sub:  #6b7280;
    --border:    #e5e7eb;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei",
                 "PingFang SC", "Noto Sans SC", sans-serif;
    line-height: 1.7;
    color: var(--text-main);
    background: var(--gray-50);
}
a { text-decoration: none; color: var(--primary); transition: var(--transition); }
a:hover { color: var(--primary-dark); }
img { max-width: 100%; display: block; }

/* ===== 顶部导航 ===== */
.top-nav {
    background: linear-gradient(135deg, #047857, #059669);
    position: sticky; top: 0; z-index: 100;
    box-shadow: 0 2px 12px rgba(5,150,105,0.3);
}
.top-nav-inner {
    max-width: 1200px; margin: 0 auto;
    display: flex; align-items: center;
    padding: 0 1.5rem; height: 56px;
}
.logo {
    font-weight: 700; font-size: 1.05rem;
    color: white !important; white-space: nowrap;
    display: flex; align-items: center; gap: 4px;
}
.nav-links {
    list-style: none; display: flex; align-items: center;
    gap: 0.2rem; margin-left: auto;
}
.nav-links > li > a,
.nav-links > li > .nav-dropdown-toggle {
    color: rgba(255,255,255,0.85); padding: 0.4rem 0.65rem;
    border-radius: 6px; font-size: 0.88rem;
    cursor: pointer; background: none; border: none;
    display: inline-flex; align-items: center; gap: 3px;
    transition: var(--transition);
}
.nav-links a:hover,
.nav-links a.active,
.nav-dropdown-toggle:hover,
.nav-dropdown-toggle.active {
    background: rgba(255,255,255,0.15); color: white;
}
.nav-arrow { font-size: 0.6rem; opacity: 0.7; }

/* 下拉菜单 */
.nav-dropdown { position: relative; }
.nav-dropdown-menu {
    display: none; position: absolute; top: calc(100% + 8px); left: 50%;
    transform: translateX(-50%);
    background: white; border-radius: var(--radius);
    box-shadow: var(--shadow-lg); border: 1px solid var(--border);
    padding: 0.5rem; min-width: 200px; z-index: 200;
}
.nav-dropdown.open .nav-dropdown-menu { display: block; }
.chapters-menu { min-width: 220px; }
.dropdown-group { padding: 0.3rem 0; }
.dropdown-group + .dropdown-group { border-top: 1px solid var(--gray-200); }
.dropdown-label {
    padding: 0.4rem 0.75rem 0.2rem; font-size: 0.72rem;
    color: var(--gray-500); font-weight: 700; text-transform: uppercase;
    letter-spacing: 0.04em;
}
.dropdown-group a {
    display: block; padding: 0.45rem 0.75rem; border-radius: var(--radius-sm);
    color: var(--text-main); font-size: 0.85rem; transition: var(--transition);
}
.dropdown-group a:hover { background: var(--primary-light); color: var(--primary); }
.dropdown-group a.active { background: var(--primary-light); color: var(--primary); font-weight: 600; }

/* 汉堡按钮 */
.nav-hamburger {
    display: none; background: none; border: none; cursor: pointer;
    padding: 6px; margin-left: auto; flex-direction: column;
    gap: 5px; align-items: center; justify-content: center;
}
.nav-hamburger span {
    display: block; width: 22px; height: 2px;
    background: white; border-radius: 2px; transition: var(--transition);
}

/* ===== 侧边栏 ===== */
.nav-overlay {
    display: none; position: fixed; inset: 0;
    background: rgba(0,0,0,0.5); z-index: 1100;
    backdrop-filter: blur(2px); -webkit-backdrop-filter: blur(2px);
}
.nav-overlay.show { display: block; }
.nav-sidebar {
    position: fixed; top: 0; right: -300px; width: 280px;
    height: 100vh; background: white; z-index: 1200;
    overflow-y: auto; transition: right 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: -4px 0 32px rgba(0,0,0,0.2);
}
.nav-sidebar.open { right: 0; }
.sidebar-header {
    display: flex; justify-content: space-between; align-items: center;
    padding: 0 20px; height: 60px;
    background: linear-gradient(135deg, #047857, #059669);
    color: white; font-weight: 600; font-size: 0.92rem;
    position: sticky; top: 0; z-index: 1;
}
.sidebar-close {
    background: none; border: none; color: rgba(255,255,255,0.8);
    font-size: 1.2rem; cursor: pointer; padding: 4px 8px;
    line-height: 1; transition: color 0.15s; border-radius: 4px;
}
.sidebar-close:hover { color: white; background: rgba(255,255,255,0.15); }
.sidebar-body { padding: 8px 0 32px; }
.sidebar-section {
    padding: 12px 20px 4px; font-size: 0.7rem; font-weight: 700;
    color: #9ca3af; text-transform: uppercase; letter-spacing: 0.06em;
    margin-top: 4px;
}
.sidebar-link {
    display: block; padding: 10px 20px; color: var(--text-main);
    text-decoration: none; font-size: 0.88rem;
    border-left: 3px solid transparent; transition: all 0.15s;
}
.sidebar-link:hover { background: var(--primary-light); color: var(--primary); border-left-color: #a7f3d0; }
.sidebar-link.active { background: #d1fae5; color: var(--primary-dark); border-left-color: var(--primary); font-weight: 600; }

/* FAB */
.fab-home {
    position: fixed; bottom: 28px; right: 24px;
    width: 50px; height: 50px; border-radius: 50%;
    background: linear-gradient(135deg, #059669, #047857);
    display: flex; align-items: center; justify-content: center;
    font-size: 1.4rem; box-shadow: 0 4px 12px rgba(5,150,105,0.4);
    z-index: 900; transition: var(--transition); text-decoration: none;
}
.fab-home:hover { transform: translateY(-2px); box-shadow: 0 6px 16px rgba(5,150,105,0.5); }

/* ===== 面包屑 ===== */
.breadcrumb {
    max-width: 1200px; margin: 0.8rem auto 0; padding: 0 1.5rem;
    font-size: 0.8rem; color: var(--gray-500);
    display: flex; align-items: center; gap: 0.4rem; flex-wrap: wrap;
}
.breadcrumb a { color: var(--primary); }
.breadcrumb a:hover { text-decoration: underline; }

/* ===== 页面 Hero ===== */
.page-hero {
    text-align: center; padding: 2.5rem 1.5rem 2rem;
    background: linear-gradient(135deg, #ecfdf5, #d1fae5, #a7f3d0);
    border-bottom: 1px solid #a7f3d0;
}
.page-hero h1 {
    font-size: 1.8rem; color: var(--primary-dark);
    margin-bottom: 0.5rem; line-height: 1.3;
}
.page-hero .subtitle {
    font-size: 1rem; color: var(--gray-600); max-width: 640px; margin: 0 auto;
}
.page-hero .hero-tag {
    display: inline-block; background: #059669; color: white;
    padding: 0.2rem 0.8rem; border-radius: 20px; font-size: 0.78rem;
    margin-bottom: 0.8rem; font-weight: 600;
}

/* ===== 主内容区 ===== */
.main-content {
    max-width: 1200px; margin: 1.5rem auto; padding: 0 1.5rem;
}

/* ===== 卡片通用 ===== */
.section-card {
    background: white; border-radius: var(--radius); padding: 1.8rem;
    box-shadow: var(--shadow); margin-bottom: 1.5rem;
    border: 1px solid var(--border);
}
.section-card h2 {
    font-size: 1.25rem; color: var(--heading-color);
    margin-bottom: 1rem; padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--primary-light);
    display: flex; align-items: center; gap: 0.4rem;
}

/* ===== 数据表格 ===== */
.data-table {
    width: 100%; border-collapse: collapse; font-size: 0.88rem;
    margin: 1rem 0;
}
.data-table th {
    background: var(--primary-light); color: var(--primary-dark);
    padding: 0.65rem 0.8rem; text-align: left; font-weight: 600;
    border-bottom: 2px solid #a7f3d0; white-space: nowrap;
}
.data-table td {
    padding: 0.6rem 0.8rem; border-bottom: 1px solid var(--gray-200);
    vertical-align: top;
}
.data-table tr:hover { background: var(--gray-50); }
.data-table .highlight { background: #ecfdf5; }

/* ===== 知识卡片 ===== */
.knowledge-card {
    background: white; border-radius: var(--radius); padding: 1.2rem 1.4rem;
    border-left: 4px solid var(--primary); box-shadow: var(--shadow);
    margin-bottom: 1rem; transition: var(--transition);
}
.knowledge-card:hover { box-shadow: var(--shadow-md); transform: translateY(-1px); }
.knowledge-card .kc-title {
    font-weight: 700; font-size: 1rem; color: var(--heading-color);
    margin-bottom: 0.4rem; display: flex; align-items: center; gap: 0.4rem;
}
.knowledge-card .kc-body { font-size: 0.9rem; color: var(--text-main); line-height: 1.8; }
.knowledge-card .kc-tip {
    margin-top: 0.6rem; padding: 0.5rem 0.8rem; background: var(--primary-light);
    border-radius: var(--radius-sm); font-size: 0.82rem; color: var(--primary-dark);
}
.knowledge-card .kc-link {
    display: inline-block; margin-top: 0.5rem; font-size: 0.82rem;
    color: var(--primary); font-weight: 600;
}
.knowledge-card .kc-link:hover { text-decoration: underline; }

/* ===== 彩色边框卡片变体 ===== */
.knowledge-card.border-blue   { border-left-color: #2563eb; }
.knowledge-card.border-cyan   { border-left-color: #0891b2; }
.knowledge-card.border-red    { border-left-color: #dc2626; }
.knowledge-card.border-purple { border-left-color: #7c3aed; }
.knowledge-card.border-orange { border-left-color: #d97706; }
.knowledge-card.border-rose   { border-left-color: #e11d48; }
.knowledge-card.border-teal   { border-left-color: #0f766e; }

/* ===== 流程图/知识图谱 ===== */
.flow-chain {
    display: flex; align-items: stretch; gap: 0;
    overflow-x: auto; padding: 1rem 0; margin: 1rem 0;
}
.flow-step {
    flex: 1; min-width: 140px; padding: 1rem;
    text-align: center; border-radius: var(--radius-sm);
    font-size: 0.85rem; position: relative;
}
.flow-step .fs-icon { font-size: 1.6rem; margin-bottom: 0.4rem; }
.flow-step .fs-label { font-weight: 700; font-size: 0.78rem; margin-bottom: 0.3rem; }
.flow-step .fs-text { font-size: 0.82rem; color: var(--gray-600); line-height: 1.5; }
.flow-arrow {
    display: flex; align-items: center; justify-content: center;
    font-size: 1.4rem; color: var(--gray-400); min-width: 30px;
    font-weight: 700;
}

.flow-step.step-anatomy   { background: #eff6ff; color: #1e40af; }
.flow-step.step-physiology { background: #ecfdf5; color: #047857; }
.flow-step.step-pathology  { background: #fef2f2; color: #991b1b; }
.flow-step.step-pharmacology { background: #f5f3ff; color: #5b21b6; }

/* ===== 搜索框 ===== */
.search-box {
    display: flex; align-items: center; gap: 0.5rem;
    background: white; border: 2px solid var(--gray-200);
    border-radius: 30px; padding: 0.5rem 1rem; margin-bottom: 1.5rem;
    transition: var(--transition); max-width: 500px;
}
.search-box:focus-within { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(5,150,105,0.15); }
.search-box input {
    flex: 1; border: none; outline: none; font-size: 0.92rem;
    background: transparent; color: var(--text-main);
}
.search-box .search-icon { font-size: 1.1rem; color: var(--gray-400); }

/* ===== 标签/徽章 ===== */
.badge {
    display: inline-block; padding: 0.15rem 0.55rem; border-radius: 20px;
    font-size: 0.72rem; font-weight: 600;
}
.badge-green  { background: #d1fae5; color: #047857; }
.badge-red    { background: #fee2e2; color: #991b1b; }
.badge-blue   { background: #dbeafe; color: #1e40af; }
.badge-orange { background: #fef3c7; color: #92400e; }
.badge-purple { background: #ede9fe; color: #5b21b6; }
.badge-gray   { background: #f3f4f6; color: #4b5563; }

/* ===== 引导区 ===== */
.cta-section {
    background: linear-gradient(135deg, #ecfdf5, #d1fae5);
    border: 2px solid #a7f3d0; border-radius: var(--radius);
    padding: 2rem; text-align: center; margin: 2rem 0;
}
.cta-section h3 { color: var(--primary-dark); margin-bottom: 0.6rem; font-size: 1.2rem; }
.cta-section p { color: var(--gray-600); margin-bottom: 1rem; }
.cta-btn {
    display: inline-block; padding: 0.6rem 1.5rem;
    background: var(--primary); color: white; border-radius: 30px;
    font-weight: 600; font-size: 0.92rem; transition: var(--transition);
    text-decoration: none;
}
.cta-btn:hover { background: var(--primary-dark); color: white; transform: translateY(-1px); }

/* ===== 药物卡片 ===== */
.drug-card {
    background: white; border-radius: var(--radius); padding: 1.2rem 1.4rem;
    box-shadow: var(--shadow); margin-bottom: 1rem;
    border: 1px solid var(--border); transition: var(--transition);
}
.drug-card:hover { box-shadow: var(--shadow-md); }
.drug-card .dc-header {
    display: flex; align-items: center; gap: 0.5rem; margin-bottom: 0.6rem;
}
.drug-card .dc-name { font-weight: 700; font-size: 1rem; color: var(--heading-color); }
.drug-card .dc-category {
    font-size: 0.72rem; padding: 0.1rem 0.5rem; border-radius: 20px;
    background: var(--primary-light); color: var(--primary-dark); font-weight: 600;
}
.drug-card .dc-body { font-size: 0.88rem; line-height: 1.8; }
.drug-card .dc-row { display: flex; gap: 0.4rem; margin-bottom: 0.3rem; }
.drug-card .dc-label { font-weight: 600; color: var(--gray-600); min-width: 65px; flex-shrink: 0; }
.drug-card .dc-warn {
    margin-top: 0.5rem; padding: 0.5rem 0.8rem;
    background: #fef3c7; border-radius: var(--radius-sm);
    font-size: 0.82rem; color: #92400e;
    border-left: 3px solid #d97706;
}

/* ===== Tab 切换 ===== */
.tab-nav {
    display: flex; gap: 0; border-bottom: 2px solid var(--gray-200);
    margin-bottom: 1.5rem; overflow-x: auto;
}
.tab-btn {
    padding: 0.6rem 1.2rem; font-size: 0.88rem; font-weight: 600;
    border: none; background: none; cursor: pointer;
    color: var(--gray-500); border-bottom: 3px solid transparent;
    margin-bottom: -2px; transition: var(--transition); white-space: nowrap;
}
.tab-btn:hover { color: var(--primary); }
.tab-btn.active { color: var(--primary); border-bottom-color: var(--primary); }
.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* ===== 提示框 ===== */
.tip-box {
    padding: 1rem 1.2rem; border-radius: var(--radius-sm);
    margin: 1rem 0; font-size: 0.88rem; line-height: 1.7;
}
.tip-box.tip-green  { background: #ecfdf5; border-left: 4px solid #059669; color: #047857; }
.tip-box.tip-blue   { background: #eff6ff; border-left: 4px solid #2563eb; color: #1e40af; }
.tip-box.tip-yellow { background: #fefce8; border-left: 4px solid #ca8a04; color: #854d0e; }
.tip-box.tip-red    { background: #fef2f2; border-left: 4px solid #dc2626; color: #991b1b; }

/* ===== Footer ===== */
.site-footer {
    text-align: center; padding: 2rem 1rem; margin-top: 3rem;
    border-top: 1px solid var(--gray-200); color: var(--gray-500);
    font-size: 0.85rem; background: white;
}
.site-footer:empty { display: none; }

/* ===== 首页特有 ===== */
.index-hero {
    text-align: center; padding: 3rem 1.5rem 2.5rem;
    background: linear-gradient(135deg, #ecfdf5, #d1fae5, #a7f3d0);
    border-bottom: 1px solid #a7f3d0;
}
.index-hero .hero-badge {
    display: inline-block; background: var(--primary); color: white;
    padding: 0.3rem 1rem; border-radius: 20px; font-size: 0.8rem;
    font-weight: 600; margin-bottom: 1rem;
}
.index-hero h1 {
    font-size: 2rem; color: var(--primary-dark); margin-bottom: 0.6rem;
}
.index-hero .hero-sub {
    font-size: 1.05rem; color: var(--gray-600); max-width: 600px; margin: 0 auto;
}

/* 模块卡片网格 */
.module-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
    gap: 0.8rem; margin: 1.2rem 0;
}
.module-card {
    background: white; border-radius: var(--radius);
    box-shadow: var(--shadow); border: 1px solid var(--border);
    transition: var(--transition); display: flex; align-items: stretch;
    text-decoration: none; color: var(--text-main); overflow: hidden;
}
.module-card:hover {
    box-shadow: var(--shadow-md); transform: translateY(-2px); color: var(--text-main);
}
.mc-accent {
    width: 4px; flex-shrink: 0;
}
.mc-inner {
    display: flex; align-items: center; gap: 0.85rem;
    padding: 0.85rem 1rem; flex: 1; min-width: 0;
}
.module-card .mc-icon {
    font-size: 1.45rem; flex-shrink: 0;
    width: 42px; height: 42px; border-radius: 10px;
    display: flex; align-items: center; justify-content: center;
    background: var(--primary-light);
}
.module-card .mc-body { flex: 1; min-width: 0; }
.module-card .mc-title {
    font-weight: 700; font-size: 0.9rem; color: var(--heading-color); margin-bottom: 0.18rem;
}
.module-card .mc-desc {
    font-size: 0.76rem; color: var(--gray-500); line-height: 1.45;
    white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.module-card .mc-tag {
    display: inline-block; margin-top: 0.28rem; font-size: 0.66rem;
    padding: 0.1rem 0.45rem; border-radius: 20px;
    background: var(--primary-light); color: var(--primary-dark); font-weight: 600;
}
.mc-btn {
    flex-shrink: 0; align-self: center; margin-right: 0.9rem;
    padding: 0.32rem 0.8rem; border-radius: 7px;
    font-size: 0.73rem; font-weight: 700; color: white;
    white-space: nowrap; background: var(--primary);
    transition: opacity 0.15s;
}
.module-card:hover .mc-btn { opacity: 0.82; }
/* 颜色变体 */
.mc-green .mc-accent  { background: #059669; }
.mc-green .mc-icon    { background: #d1fae5; }
.mc-green .mc-title   { color: #065f46; }
.mc-green .mc-btn     { background: #059669; }
.mc-teal  .mc-accent  { background: #0d9488; }
.mc-teal  .mc-icon    { background: #ccfbf1; }
.mc-teal  .mc-title   { color: #0f766e; }
.mc-teal  .mc-btn     { background: #0d9488; }
.mc-blue  .mc-accent  { background: #0284c7; }
.mc-blue  .mc-icon    { background: #e0f2fe; }
.mc-blue  .mc-title   { color: #0369a1; }
.mc-blue  .mc-btn     { background: #0284c7; }
.mc-red   .mc-accent  { background: #be123c; }
.mc-red   .mc-icon    { background: #ffe4e6; }
.mc-red   .mc-title   { color: #9f1239; }
.mc-red   .mc-btn     { background: #be123c; }
.mc-purple .mc-accent { background: #7c3aed; }
.mc-purple .mc-icon   { background: #ede9fe; }
.mc-purple .mc-title  { color: #5b21b6; }
.mc-purple .mc-btn    { background: #7c3aed; }
.mc-orange .mc-accent { background: #d97706; }
.mc-orange .mc-icon   { background: #fef3c7; }
.mc-orange .mc-title  { color: #92400e; }
.mc-orange .mc-btn    { background: #d97706; }
.mc-cyan  .mc-accent  { background: #0891b2; }
.mc-cyan  .mc-icon    { background: #e0f2fe; }
.mc-cyan  .mc-title   { color: #0e7490; }
.mc-cyan  .mc-btn     { background: #0891b2; }

/* ===== 课程引导区 ===== */
.course-promo {
    background: linear-gradient(135deg, #f0fdf4, #dcfce7);
    border: 2px dashed #86efac; border-radius: var(--radius);
    padding: 2rem; margin: 2rem 0;
}
.course-promo h3 { color: var(--primary-dark); margin-bottom: 0.8rem; text-align: center; }
.course-grid {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 0.8rem; margin-top: 1rem;
}
.course-mini {
    display: flex; align-items: center; gap: 0.6rem;
    background: white; border-radius: var(--radius-sm); padding: 0.7rem 1rem;
    text-decoration: none; color: var(--text-main); transition: var(--transition);
    border: 1px solid var(--gray-200);
}
.course-mini:hover { border-color: var(--primary); background: #ecfdf5; }
.course-mini .cm-icon { font-size: 1.3rem; }
.course-mini .cm-name { font-weight: 600; font-size: 0.88rem; }
.course-mini .cm-tag {
    margin-left: auto; font-size: 0.68rem; padding: 0.1rem 0.4rem;
    background: #fef3c7; color: #92400e; border-radius: 10px; font-weight: 600;
}

/* ===== 延伸阅读链接 ===== */
.extend-links {
    display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 0.8rem;
}
.extend-link {
    display: inline-flex; align-items: center; gap: 0.3rem;
    padding: 0.3rem 0.7rem; border-radius: 20px; font-size: 0.78rem;
    font-weight: 600; text-decoration: none; transition: var(--transition);
}
.extend-link.el-anatomy   { background: #eff6ff; color: #1e40af; }
.extend-link.el-physiology { background: #ecfdf5; color: #047857; }
.extend-link.el-pathology  { background: #fef2f2; color: #991b1b; }
.extend-link.el-pharmacology { background: #f5f3ff; color: #5b21b6; }
.extend-link:hover { filter: brightness(0.95); transform: translateY(-1px); }

/* ===== 模块前后导航条 ===== */
.module-nav-bar {
    max-width: 860px; margin: 0 auto 1.5rem;
    padding: 0 1.5rem;
    display: flex; justify-content: space-between; align-items: center; gap: 0.6rem;
}
.mnav-prev, .mnav-home, .mnav-next {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 0.55rem 1rem; border-radius: 8px;
    font-size: 0.84rem; font-weight: 600;
    text-decoration: none; transition: var(--transition);
    white-space: nowrap; flex: 1;
}
.mnav-prev {
    background: #f3f4f6; color: #374151; border: 1px solid #e5e7eb;
}
.mnav-prev:hover { background: #e5e7eb; color: #111827; }
.mnav-home {
    background: #f0fdf4; color: #059669; border: 1px solid #a7f3d0;
}
.mnav-home:hover { background: #dcfce7; color: #047857; }
.mnav-next {
    background: var(--primary); color: white !important;
}
.mnav-next:hover { background: var(--primary-dark); color: white !important; }

/* ===== Responsive ===== */
@media (max-width: 800px) {
    .module-grid { grid-template-columns: 1fr; }
    .course-grid { grid-template-columns: 1fr 1fr; }
    .flow-chain { flex-direction: column; align-items: center; }
    .flow-arrow { transform: rotate(90deg); }
}
@media (max-width: 640px) {
    .page-hero { padding: 1.8rem 1rem 1.5rem; }
    .page-hero h1 { font-size: 1.4rem; }
    .main-content { padding: 0 1rem; margin: 1rem auto; }
    .section-card { padding: 1.2rem 1rem; }
    .nav-links { display: none; }
    .nav-hamburger { display: flex; }
    .index-hero { padding: 2rem 1rem 1.5rem; }
    .index-hero h1 { font-size: 1.5rem; }
    .course-grid { grid-template-columns: 1fr; }
    .tab-nav { gap: 0; }
    .tab-btn { padding: 0.5rem 0.8rem; font-size: 0.82rem; }
}