/* Design Ref: §4.5 — 레이아웃, 타이포그래피, 사이드바, 반응형, 다크모드 */

/* === CSS Variables === */
:root {
  --sidebar-width: 280px;
  --content-max-width: 900px;
  --transition: 0.3s ease;
}

[data-theme="light"] {
  --bg: #ffffff;
  --bg-secondary: #f8f9fa;
  --text: #333333;
  --text-secondary: #666666;
  --sidebar-bg: #f8f9fa;
  --sidebar-border: #e9ecef;
  --sidebar-hover: #e9ecef;
  --sidebar-active: #4a9eff;
  --sidebar-active-bg: #e8f4fd;
  --code-bg: #f5f5f5;
  --info-bg: #e8f4fd;
  --info-border: #4a9eff;
  --warning-bg: #fff8e1;
  --warning-border: #ff9800;
  --card-bg: #ffffff;
  --card-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  --border: #e9ecef;
  --link: #4a9eff;
  --prompt-good-bg: #e8f5e9;
  --prompt-good-border: #4caf50;
  --prompt-bad-bg: #ffebee;
  --prompt-bad-border: #f44336;
  --practice-bg: #f3e5f5;
  --practice-border: #9c27b0;
  --table-header-bg: #f1f3f5;
  --table-border: #dee2e6;
  --table-stripe: #f8f9fa;
  --scrollbar-thumb: #c1c1c1;
  --scrollbar-track: #f1f1f1;
}

[data-theme="dark"] {
  --bg: #1a1a2e;
  --bg-secondary: #16213e;
  --text: #e0e0e0;
  --text-secondary: #a0a0a0;
  --sidebar-bg: #16213e;
  --sidebar-border: #2a2a4a;
  --sidebar-hover: #2a2a4a;
  --sidebar-active: #64b5f6;
  --sidebar-active-bg: #1a3a5c;
  --code-bg: #0d1117;
  --info-bg: #1a3a5c;
  --info-border: #64b5f6;
  --warning-bg: #3e2723;
  --warning-border: #ff9800;
  --card-bg: #16213e;
  --card-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
  --border: #2a2a4a;
  --link: #64b5f6;
  --prompt-good-bg: #1b3a1b;
  --prompt-good-border: #4caf50;
  --prompt-bad-bg: #3a1b1b;
  --prompt-bad-border: #f44336;
  --practice-bg: #2a1a3a;
  --practice-border: #ce93d8;
  --table-header-bg: #1e2a3a;
  --table-border: #2a2a4a;
  --table-stripe: #1e2a3a;
  --scrollbar-thumb: #444;
  --scrollbar-track: #1a1a2e;
}

/* === Reset & Base === */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  display: flex;
  min-height: 100vh;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Noto Sans KR', sans-serif;
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.7;
  transition: background-color var(--transition), color var(--transition);
}

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

a:hover {
  text-decoration: underline;
}

/* === Scrollbar === */
::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: var(--scrollbar-track);
}

::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: 3px;
}

/* === Sidebar === */
#sidebar {
  width: var(--sidebar-width);
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  background: var(--sidebar-bg);
  border-right: 1px solid var(--sidebar-border);
  overflow-y: auto;
  z-index: 50;
  display: flex;
  flex-direction: column;
  transition: background-color var(--transition);
}

.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 1rem;
  border-bottom: 1px solid var(--sidebar-border);
  position: sticky;
  top: 0;
  background: var(--sidebar-bg);
  z-index: 1;
}

.sidebar-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
}

#theme-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.3rem 0.5rem;
  cursor: pointer;
  font-size: 1.1rem;
  transition: background var(--transition);
}

#theme-toggle:hover {
  background: var(--sidebar-hover);
}

.nav-list {
  list-style: none;
  padding: 0.5rem 0;
  flex: 1;
}

.nav-item {
  border-bottom: 1px solid var(--sidebar-border);
}

.nav-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.75rem 1rem;
  background: none;
  border: none;
  color: var(--text);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  text-align: left;
  transition: background var(--transition);
}

.nav-title:hover {
  background: var(--sidebar-hover);
}

.nav-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 6px;
  background: var(--border);
  font-size: 0.75rem;
  font-weight: 700;
  flex-shrink: 0;
}

.nav-item.active .nav-number {
  background: var(--sidebar-active);
  color: #fff;
}

.nav-arrow {
  margin-left: auto;
  font-size: 0.7rem;
  transition: transform var(--transition);
}

.nav-item.active .nav-arrow {
  transform: rotate(90deg);
}

.nav-sub {
  list-style: none;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.nav-item.active .nav-sub {
  max-height: 800px;
}

.nav-sub a {
  display: block;
  padding: 0.4rem 1rem 0.4rem 3rem;
  font-size: 0.82rem;
  color: var(--text-secondary);
  transition: all var(--transition);
  border-left: 3px solid transparent;
}

.nav-sub a:hover {
  background: var(--sidebar-hover);
  color: var(--text);
  text-decoration: none;
}

.nav-sub a.current {
  color: var(--sidebar-active);
  border-left-color: var(--sidebar-active);
  background: var(--sidebar-active-bg);
  font-weight: 600;
}

.sidebar-footer {
  padding: 1rem;
  border-top: 1px solid var(--sidebar-border);
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-align: center;
}

/* === Main Content === */
#content {
  margin-left: var(--sidebar-width);
  flex: 1;
  padding: 2rem 2.5rem;
  max-width: calc(var(--content-max-width) + var(--sidebar-width) + 5rem);
  min-height: 100vh;
}

#module-container {
  max-width: var(--content-max-width);
}

/* === Module Content Styles === */
.module h2 {
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  color: var(--text);
  padding-bottom: 0.75rem;
  border-bottom: 3px solid var(--sidebar-active);
}

.module-intro {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  line-height: 1.8;
}

.module h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2.5rem 0 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  color: var(--text);
}

.module h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1.5rem 0 0.75rem;
  color: var(--text);
}

.module p {
  margin-bottom: 1rem;
}

.module ul,
.module ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

.module li {
  margin-bottom: 0.4rem;
}

/* === AI Term Highlight === */
.ai-term {
  background: linear-gradient(transparent 60%, #ffe066 60%);
  padding: 0 2px;
  border-radius: 2px;
  font-weight: 700;
}

[data-theme="dark"] .ai-term {
  background: linear-gradient(transparent 60%, rgba(255, 193, 7, 0.3) 60%);
}

/* === Info Box === */
.info-box {
  background: var(--info-bg);
  border-left: 4px solid var(--info-border);
  padding: 1rem 1.25rem;
  border-radius: 0 8px 8px 0;
  margin: 1rem 0;
  line-height: 1.7;
}

/* === Warning Box === */
.warning-box {
  background: var(--warning-bg);
  border-left: 4px solid var(--warning-border);
  padding: 1rem 1.25rem;
  border-radius: 0 8px 8px 0;
  margin: 1rem 0;
  line-height: 1.7;
}

/* === Comparison Table === */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.9rem;
}

.comparison-table thead {
  background: var(--table-header-bg);
}

.comparison-table th,
.comparison-table td {
  padding: 0.65rem 0.85rem;
  border: 1px solid var(--table-border);
  text-align: left;
  vertical-align: top;
}

.comparison-table th {
  font-weight: 600;
  white-space: nowrap;
}

.comparison-table tbody tr:nth-child(even) {
  background: var(--table-stripe);
}

/* === Step List === */
.step-list {
  counter-reset: step;
  list-style: none;
  padding-left: 0;
}

.step-list > li {
  position: relative;
  padding: 1rem 1rem 1rem 3.5rem;
  margin-bottom: 0.75rem;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid var(--border);
}

.step-list > li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 1rem;
  top: 1rem;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--sidebar-active);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
}

.step-list > li p {
  margin: 0.3rem 0 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* === Prompt Example === */
.prompt-example {
  margin: 1rem 0;
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border);
}

.prompt-example .prompt-label {
  padding: 0.5rem 1rem;
  font-size: 0.8rem;
  font-weight: 600;
  background: var(--prompt-bad-bg);
  color: var(--prompt-bad-border);
  border-bottom: 1px solid var(--border);
}

.prompt-example.good .prompt-label {
  background: var(--prompt-good-bg);
  color: var(--prompt-good-border);
}

.prompt-example pre {
  margin: 0;
  border-radius: 0;
}

.prompt-example code {
  font-size: 0.85rem;
  line-height: 1.6;
}

/* === Practice Section === */
.practice-section {
  background: var(--practice-bg);
  border-left: 4px solid var(--practice-border);
  padding: 1.25rem;
  border-radius: 0 8px 8px 0;
  margin: 1.5rem 0;
}

.practice-section h4 {
  margin-top: 0;
  color: var(--practice-border);
}

/* === Diagram Container === */
.diagram-container {
  margin: 1rem 0;
  padding: 1.5rem;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid var(--border);
  overflow-x: auto;
  text-align: center;
}

/* === Code Blocks === */
pre[class*="language-"] {
  border-radius: 8px;
  margin: 1rem 0;
  font-size: 0.85rem;
}

code {
  font-family: 'Cascadia Code', 'Fira Code', Consolas, 'Courier New', monospace;
  font-size: 0.88em;
}

:not(pre) > code {
  background: var(--code-bg);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-size: 0.85em;
}

/* === Module Navigation === */
#module-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 2px solid var(--border);
}

.module-nav-btn {
  display: inline-block;
  padding: 0.6rem 1.2rem;
  background: var(--sidebar-active);
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  transition: opacity var(--transition);
}

.module-nav-btn:hover {
  opacity: 0.85;
  text-decoration: none;
  color: #fff;
}

.module-nav-btn.disabled {
  opacity: 0.3;
  cursor: not-allowed;
  pointer-events: none;
}

a.nav-title {
  text-decoration: none;
  color: inherit;
}

a.nav-title:hover {
  text-decoration: none;
}

#current-module-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 600;
}

/* === Loading & Error === */
.loading-placeholder {
  text-align: center;
  padding: 4rem 2rem;
  color: var(--text-secondary);
  font-size: 1.1rem;
}

.error-message {
  text-align: center;
  padding: 3rem 2rem;
  background: var(--warning-bg);
  border-radius: 12px;
  border: 1px solid var(--warning-border);
}

.error-message h2 {
  border: none;
  margin-bottom: 1rem;
}

/* === Scroll to Top === */
#scroll-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--sidebar-active);
  color: #fff;
  border: none;
  cursor: pointer;
  font-size: 1.2rem;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition), visibility var(--transition);
  z-index: 40;
}

#scroll-top.visible {
  opacity: 1;
  visibility: visible;
}

#scroll-top:hover {
  transform: scale(1.1);
}

/* === Mobile Menu Toggle === */
#menu-toggle {
  display: none;
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 60;
  width: 44px;
  height: 44px;
  border-radius: 8px;
  background: var(--card-bg);
  border: 1px solid var(--border);
  cursor: pointer;
  box-shadow: var(--card-shadow);
  align-items: center;
  justify-content: center;
}

.hamburger,
.hamburger::before,
.hamburger::after {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text);
  border-radius: 1px;
  transition: all var(--transition);
}

.hamburger {
  position: relative;
}

.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  left: 0;
}

.hamburger::before {
  top: -6px;
}

.hamburger::after {
  top: 6px;
}

#menu-toggle.active .hamburger {
  background: transparent;
}

#menu-toggle.active .hamburger::before {
  top: 0;
  transform: rotate(45deg);
}

#menu-toggle.active .hamburger::after {
  top: 0;
  transform: rotate(-45deg);
}

#sidebar-overlay {
  display: none;
}

/* === Responsive: Mobile === */
@media (max-width: 768px) {
  #sidebar {
    transform: translateX(-100%);
    transition: transform var(--transition);
    width: 280px;
    z-index: 100;
  }

  #sidebar.open {
    transform: translateX(0);
  }

  #content {
    margin-left: 0;
    padding: 1.5rem 1rem;
    padding-top: 4rem;
  }

  #menu-toggle {
    display: flex;
  }

  #sidebar-overlay {
    display: block;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 90;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition), visibility var(--transition);
  }

  #sidebar-overlay.open {
    opacity: 1;
    visibility: visible;
  }

  .module h2 {
    font-size: 1.4rem;
  }

  .module h3 {
    font-size: 1.15rem;
  }

  .comparison-table {
    font-size: 0.8rem;
  }

  .comparison-table th,
  .comparison-table td {
    padding: 0.5rem;
  }

  #module-nav {
    flex-direction: column;
    gap: 0.75rem;
  }

  #scroll-top {
    bottom: 1rem;
    right: 1rem;
  }
}

/* === Responsive: Tablet === */
@media (min-width: 769px) and (max-width: 1024px) {
  :root {
    --sidebar-width: 240px;
  }

  #content {
    padding: 2rem 1.5rem;
  }
}

/* === Print === */
@media print {
  #sidebar,
  #menu-toggle,
  #scroll-top,
  #module-nav,
  #sidebar-overlay {
    display: none !important;
  }

  #content {
    margin-left: 0;
    max-width: 100%;
  }
}

/* === Side Panel === */
.side-panel-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  margin-left: 4px;
  padding: 0;
  font-size: 14px;
  line-height: 1;
  color: var(--text-secondary);
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: pointer;
  vertical-align: middle;
  transition: var(--transition);
}
.side-panel-btn:hover {
  color: var(--sidebar-active);
  border-color: var(--sidebar-active);
  background: var(--sidebar-active-bg);
}

.side-panel {
  position: fixed;
  top: 0;
  right: -50vw;
  width: 50vw;
  height: 100vh;
  background: var(--bg);
  border-left: 2px solid var(--border);
  z-index: 2000;
  display: flex;
  flex-direction: column;
  transition: right 0.35s ease;
  box-shadow: -4px 0 20px rgba(0, 0, 0, 0.15);
}
.side-panel.open {
  right: 0;
}
.side-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-secondary);
  flex-shrink: 0;
}
.side-panel-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
}
.side-panel-close {
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  color: var(--text-secondary);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
  transition: var(--transition);
}
.side-panel-close:hover {
  color: #f44336;
  border-color: #f44336;
  background: #ffebee;
}
.side-panel-iframe {
  flex: 1;
  width: 100%;
  border: none;
}
.side-panel-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.3);
  z-index: 1999;
}
.side-panel-overlay.open {
  display: block;
}

/* Side panel open: shrink content */
body.side-panel-active #content {
  margin-right: 50vw;
  transition: margin-right 0.35s ease;
}

@media (max-width: 768px) {
  .side-panel {
    width: 90vw;
    right: -90vw;
  }
  body.side-panel-active #content {
    margin-right: 0;
  }
}

/* === Search === */
.search-container {
  padding: 0.5rem 1rem;
  border-bottom: 1px solid var(--sidebar-border);
  position: relative;
}

.search-input {
  width: 100%;
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--text);
  font-size: 0.85rem;
  outline: none;
  transition: border-color var(--transition);
}

.search-input:focus {
  border-color: var(--sidebar-active);
  box-shadow: 0 0 0 2px rgba(74, 158, 255, 0.2);
}

.search-input::placeholder {
  color: var(--text-secondary);
}

.search-results {
  display: none;
  position: absolute;
  top: 100%;
  left: 0.5rem;
  right: 0.5rem;
  max-height: 400px;
  overflow-y: auto;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
  z-index: 200;
}

.search-result-item {
  display: block;
  padding: 0.6rem 0.85rem;
  border-bottom: 1px solid var(--border);
  color: var(--text);
  text-decoration: none;
  transition: background var(--transition);
}

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

.search-result-item:hover {
  background: var(--sidebar-hover);
  text-decoration: none;
}

.search-result-title {
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.15rem;
}

.search-result-desc {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.search-highlight {
  background: #ffe066;
  padding: 0 1px;
  border-radius: 2px;
}

[data-theme="dark"] .search-highlight {
  background: rgba(255, 193, 7, 0.35);
}

.search-no-results {
  padding: 1rem;
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* === Reduced Motion === */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }
}


/* === Progress tracking (learn check) === */
.section-check {
  display: inline-flex;
  align-items: center;
  margin-left: 0.6rem;
  cursor: pointer;
  vertical-align: middle;
  user-select: none;
}
.section-check input { display: none; }
.section-check-mark {
  display: inline-flex;
  width: 1.2rem;
  height: 1.2rem;
  border: 1.5px solid var(--border);
  border-radius: 4px;
  align-items: center;
  justify-content: center;
  color: transparent;
  font-weight: 700;
  font-size: 0.85rem;
  transition: all 0.15s ease;
  background: var(--bg);
}
.section-check:hover .section-check-mark { border-color: var(--link); }
.section-check input:checked ~ .section-check-mark {
  background: #4caf50;
  border-color: #4caf50;
  color: #fff;
}

.nav-sub a.done::before {
  content: '✓ ';
  color: #4caf50;
  font-weight: 700;
}

.progress-summary {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  margin-top: 0.7rem;
  padding-top: 0.6rem;
  border-top: 1px solid var(--border);
  font-size: 0.78rem;
  color: var(--text-secondary);
}
.progress-bar {
  display: block;
  width: 100%;
  height: 6px;
  background: var(--border);
  border-radius: 3px;
  overflow: hidden;
}
.progress-fill {
  display: block;
  height: 100%;
  background: #4caf50;
  transition: width 0.3s ease;
}
.progress-text { font-variant-numeric: tabular-nums; }

/* === Tag filter (sidebar chips) === */
.tag-filter {
  padding: 0.5rem 1rem 0.7rem 1rem;
  border-bottom: 1px solid var(--border);
  background: var(--bg-secondary);
}
.tag-filter-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.3rem;
  margin-bottom: 0.4rem;
}
.tag-filter-group:last-of-type { margin-bottom: 0; }
.tag-filter-label {
  font-size: 0.68rem;
  font-weight: 700;
  color: var(--text-secondary);
  margin-right: 0.2rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  flex: 0 0 2.4rem;
}
.tag-chip {
  font-size: 0.74rem;
  padding: 0.12rem 0.55rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.12s ease;
  font-family: inherit;
}
.tag-chip:hover { border-color: var(--link); color: var(--link); }
.tag-chip.active {
  background: var(--link);
  color: #fff;
  border-color: var(--link);
}
.tag-filter-clear {
  margin-top: 0.4rem;
  font-size: 0.7rem;
  padding: 0.15rem 0.5rem;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  text-decoration: underline;
  cursor: pointer;
  font-family: inherit;
}
.tag-filter-clear:hover { color: var(--link); }

.nav-sub li.filtered-out { display: none; }
.nav-list > .nav-item.module-filtered-out { display: none; }

/* === Home hub & module navigation (migrate-home-hub.js) === */
.home-hero {
  margin: 0 0 2rem 0;
  padding: 2.5rem 0 1.5rem 0;
  border-bottom: 1px solid var(--border);
}
.home-hero h1 {
  font-size: 2.2rem;
  margin: 0 0 0.4rem 0;
  letter-spacing: -0.02em;
}
.home-lede {
  margin: 0 0 0.4rem 0;
  font-size: 1.05rem;
  color: var(--text-secondary);
}
.home-meta {
  margin: 0;
  font-size: 0.85rem;
  color: var(--text-secondary);
  opacity: 0.85;
}
.home-section { margin: 2.5rem 0; }
.home-section h2 { margin: 0 0 1rem 0; }

.role-paths {
  width: 100%;
  border-collapse: collapse;
  margin: 0;
}
.role-paths th, .role-paths td {
  padding: 0.7rem 0.9rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}
.role-paths th {
  background: var(--bg-secondary);
  font-weight: 600;
}

.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
  margin: 0;
}
.module-card {
  display: flex;
  gap: 0.9rem;
  padding: 1rem 1.1rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--card-bg);
  text-decoration: none;
  color: var(--text);
  transition: border-color 0.15s ease, transform 0.15s ease, box-shadow 0.15s ease;
}
.module-card:hover {
  border-color: var(--link);
  transform: translateY(-2px);
  box-shadow: var(--card-shadow);
}
.module-card-num {
  flex: 0 0 auto;
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 8px;
  background: var(--link);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.05rem;
}
.module-card-body { flex: 1 1 auto; min-width: 0; }
.module-card-tag {
  display: inline-block;
  font-size: 0.72rem;
  padding: 0.1rem 0.5rem;
  border-radius: 999px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  margin-bottom: 0.35rem;
  letter-spacing: 0.02em;
}
.module-card-title {
  margin: 0 0 0.3rem 0;
  font-size: 1.05rem;
  line-height: 1.3;
}
.module-card-desc {
  margin: 0;
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.45;
}

.resource-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 0.3rem 1rem;
}
.resource-list a {
  display: block;
  padding: 0.5rem 0.7rem;
  border-radius: 6px;
  text-decoration: none;
  color: var(--text);
}
.resource-list a:hover {
  background: var(--bg-secondary);
  color: var(--link);
}

/* prev/next navigation at the bottom of each module page */
.prev-next {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 0.6rem;
  margin: 3rem 0 1rem 0;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}
.prev-next-link {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 0.7rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  color: var(--text);
  background: var(--bg-secondary);
  transition: border-color 0.15s ease, background 0.15s ease;
  min-height: 2.6rem;
}
.prev-next-link:hover {
  border-color: var(--link);
  background: var(--bg);
}
.prev-next-link.disabled {
  opacity: 0.5;
  cursor: default;
  pointer-events: none;
}
.prev-next-link.next { text-align: right; align-items: flex-end; }
.prev-next-link.home {
  align-self: stretch;
  justify-content: center;
  align-items: center;
  flex-direction: row;
  font-weight: 600;
}
.prev-next-label {
  font-size: 0.78rem;
  color: var(--text-secondary);
}
.prev-next-title {
  font-size: 0.95rem;
  line-height: 1.3;
}
@media (max-width: 640px) {
  .prev-next { grid-template-columns: 1fr; }
  .prev-next-link.next { text-align: left; align-items: flex-start; }
}