/* ============================================================
   module.css - Shared layout and content styles for all module
   pages (part1, part2, part3, part4).
   Load order in each module page:
     styles.css  ->  quiz.css  ->  module.css  ->  partN.css
   ============================================================ */

/* ----------------------------------------
   Nav: active link + logo link reset
   ---------------------------------------- */
.nav-logo {
  text-decoration: none;
}

.nav-link--active {
  color: var(--text-primary) !important;
  background: rgba(79, 195, 247, 0.1);
}

/* ----------------------------------------
   Page layout: two-column sidebar + content
   ---------------------------------------- */
.module-page-layout {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: flex-start;
  gap: 32px;
  max-width: 1200px;
  margin: 0 auto;
  padding: 100px 24px 80px;
}

/* ----------------------------------------
   Progress sidebar
   ---------------------------------------- */
.progress-sidebar {
  width: 224px;
  flex-shrink: 0;
  position: sticky;
  top: 88px;
  max-height: calc(100vh - 112px);
  overflow-y: auto;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  padding: 20px 16px;
  scrollbar-width: thin;
  scrollbar-color: var(--navy-light) transparent;
}

.progress-sidebar::-webkit-scrollbar       { width: 4px; }
.progress-sidebar::-webkit-scrollbar-thumb { background: var(--navy-light); border-radius: 2px; }

.sidebar-header {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin: 0 0 14px 4px;
}

.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sidebar-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.82rem;
  line-height: 1.4;
  border-left: 2px solid transparent;
  transition: color 0.2s, background 0.2s, border-color 0.2s;
  cursor: pointer;
  user-select: none;
}

.sidebar-link:not(.sidebar-link--upcoming):hover {
  color: var(--text-primary);
  background: rgba(79, 195, 247, 0.06);
}

.sidebar-link.active {
  color: var(--text-primary);
  background: rgba(79, 195, 247, 0.08);
  border-left-color: var(--blue-accent);
}

.sidebar-link.active .sidebar-dot {
  background: var(--blue-accent);
  box-shadow: 0 0 8px rgba(79, 195, 247, 0.7);
}

.sidebar-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--text-muted);
  flex-shrink: 0;
  transition: background 0.2s, box-shadow 0.2s;
}

.sidebar-link-text { flex: 1; }

.sidebar-link--upcoming {
  opacity: 0.38;
  cursor: default;
}

.sidebar-soon {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.05);
  border-radius: 4px;
  padding: 2px 6px;
  flex-shrink: 0;
}

/* ----------------------------------------
   Module main content area
   ---------------------------------------- */
.module-main {
  flex: 1;
  min-width: 0;
  max-width: 780px;
}

/* ----------------------------------------
   Module hero header
   ---------------------------------------- */
.module-hero {
  margin-bottom: 64px;
  padding-bottom: 48px;
  border-bottom: 1px solid var(--glass-border);
}

.module-hero-badge-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.module-hero-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.module-hero-title {
  font-size: clamp(1.9rem, 4vw, 2.8rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.15;
  color: var(--text-primary);
  margin-bottom: 14px;
}

.module-hero-subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 580px;
  margin-bottom: 24px;
}

.module-meta-row {
  display: flex;
  align-items: center;
  gap: 20px;
  margin-bottom: 20px;
}

.meta-item {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.meta-divider {
  width: 1px;
  height: 14px;
  background: var(--glass-border);
}

.module-progress-track {
  height: 3px;
  background: rgba(255, 255, 255, 0.06);
  border-radius: 2px;
  overflow: hidden;
  max-width: 320px;
}

.module-progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--blue-primary), var(--cyan));
  border-radius: 2px;
  transition: width 0.5s ease;
}

/* ----------------------------------------
   Content sections
   ---------------------------------------- */
.content-section {
  padding-bottom: 64px;
  margin-bottom: 64px;
  border-bottom: 1px solid var(--glass-border);
}

.content-section:last-of-type {
  border-bottom: none;
}

.section-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 28px;
}

.section-num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--blue-accent);
  background: rgba(79, 195, 247, 0.1);
  border: 1px solid rgba(79, 195, 247, 0.2);
  border-radius: 6px;
  padding: 4px 10px;
  flex-shrink: 0;
}

.section-heading {
  font-size: clamp(1.3rem, 2.5vw, 1.75rem);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  line-height: 1.2;
}

/* Prose inside sections */
.section-body p {
  font-size: 0.975rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 18px;
}

.section-body p:last-child { margin-bottom: 0; }

.section-body strong {
  color: var(--text-primary);
  font-weight: 600;
}

.section-body em {
  color: var(--text-secondary);
  font-style: italic;
}

/* Inline code */
.section-body code,
.key-concept-text code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  color: var(--blue-accent);
  background: rgba(79, 195, 247, 0.08);
  border: 1px solid rgba(79, 195, 247, 0.15);
  border-radius: 4px;
  padding: 1px 6px;
}

/* ----------------------------------------
   Key concept / note callout block
   ---------------------------------------- */
.key-concept-block {
  background: rgba(30, 144, 255, 0.07);
  border: 1px solid rgba(30, 144, 255, 0.2);
  border-left: 3px solid var(--blue-primary);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  margin-top: 20px;
  margin-bottom: 20px;
}

.key-concept-label {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--blue-accent);
  margin-bottom: 8px;
}

.key-concept-text {
  font-size: 0.92rem !important;
  color: var(--text-secondary);
  line-height: 1.7;
  margin: 0 !important;
}

/* ----------------------------------------
   Subsection headings (h3)
   ---------------------------------------- */
.subsection-heading {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin: 32px 0 14px;
}

/* ----------------------------------------
   Problem / weakness list (red X bullets)
   ---------------------------------------- */
.highlight-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.highlight-list li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.highlight-list li::before {
  content: '';
  display: block;
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  margin-top: 3px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none'%3E%3Ccircle cx='8' cy='8' r='7' stroke='%23f87171' stroke-width='1.2'/%3E%3Cpath d='M5.5 5.5l5 5M10.5 5.5l-5 5' stroke='%23f87171' stroke-width='1.4' stroke-linecap='round'/%3E%3C/svg%3E");
  background-size: contain;
  background-repeat: no-repeat;
}

.highlight-list li strong { color: var(--text-primary); font-weight: 600; }

/* ----------------------------------------
   Examples list (blue arrow bullets)
   ---------------------------------------- */
.examples-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.examples-list li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.examples-list li::before {
  content: '';
  display: block;
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  margin-top: 3px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none'%3E%3Cpath d='M3 8h10M9 4l4 4-4 4' stroke='%234fc3f7' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-size: contain;
  background-repeat: no-repeat;
}

/* ----------------------------------------
   Expandable example cards
   ---------------------------------------- */
.example-cards {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 4px;
}

.example-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.example-card summary {
  list-style: none;
}

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

.example-card-trigger {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  cursor: pointer;
  user-select: none;
  transition: background 0.15s;
}

.example-card-trigger:hover {
  background: rgba(79, 195, 247, 0.04);
}

.example-card-icon {
  font-size: 1.1rem;
  line-height: 1;
  flex-shrink: 0;
}

.example-card-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  flex: 1;
}

.example-card-chevron {
  flex-shrink: 0;
  color: var(--text-muted);
  transition: transform 0.2s ease;
}

.example-card[open] .example-card-chevron {
  transform: rotate(180deg);
}

.example-card-body {
  padding: 0 18px 16px calc(18px + 1.1rem + 12px);
  border-top: 1px solid var(--glass-border);
}

.example-card[open] .example-card-body {
  animation: exCardFadeIn 0.18s ease;
}

@keyframes exCardFadeIn {
  from { opacity: 0; transform: translateY(-4px); }
  to   { opacity: 1; transform: translateY(0); }
}

.example-card-body p {
  font-size: 0.875rem !important;
  color: var(--text-secondary) !important;
  line-height: 1.7;
  margin: 12px 0 0 !important;
}

/* ----------------------------------------
   Numbered steps list
   ---------------------------------------- */
.steps-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
  counter-reset: step-counter;
}

.steps-list li {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
  counter-increment: step-counter;
}

.steps-list li::before {
  content: counter(step-counter);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  flex-shrink: 0;
  margin-top: 1px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--blue-accent);
  background: rgba(79, 195, 247, 0.1);
  border: 1px solid rgba(79, 195, 247, 0.25);
  border-radius: 50%;
}

.steps-list li strong { color: var(--text-primary); font-weight: 600; }

/* ----------------------------------------
   Mermaid diagram container
   ---------------------------------------- */
.diagram-container {
  position: relative;
  margin: 36px 0;
  padding: 48px 40px;
  border-radius: var(--radius-xl);
  border: 1px solid rgba(79, 195, 247, 0.18);
  overflow-x: auto;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 280px;
  background-color: rgba(3, 8, 18, 0.85);
  background-image:
    linear-gradient(rgba(79, 195, 247, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(79, 195, 247, 0.04) 1px, transparent 1px);
  background-size: 36px 36px;
  box-shadow:
    0 0 0 1px rgba(79, 195, 247, 0.06),
    0 0 60px rgba(30, 144, 255, 0.08),
    inset 0 1px 0 rgba(79, 195, 247, 0.12);
}

.diagram-container::before {
  content: '';
  position: absolute;
  top: 0;
  left: 10%;
  right: 10%;
  height: 1px;
  background: linear-gradient(90deg,
    transparent,
    rgba(79, 195, 247, 0.5) 30%,
    rgba(30, 144, 255, 0.6) 50%,
    rgba(79, 195, 247, 0.5) 70%,
    transparent
  );
}

.diagram-container .mermaid {
  display: flex;
  justify-content: center;
  width: 100%;
}

.diagram-container .mermaid svg {
  width: 100% !important;
  max-width: 720px;
  height: auto !important;
  min-height: 220px;
  filter: drop-shadow(0 0 12px rgba(30, 144, 255, 0.15));
}

/* ----------------------------------------
   Code block (pipeline / trace examples)
   ---------------------------------------- */
.code-block {
  position: relative;
  margin: 24px 0;
  background: rgba(3, 8, 18, 0.9);
  border: 1px solid rgba(79, 195, 247, 0.14);
  border-radius: var(--radius-md);
  overflow-x: auto;
}

.code-block-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  padding: 10px 18px 0;
}

.code-block pre {
  margin: 0;
  padding: 14px 18px 18px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--text-secondary);
  white-space: pre;
  overflow-x: auto;
}

.code-block pre .hl { color: var(--blue-accent); }
.code-block pre .hl-green { color: #86efac; }
.code-block pre .hl-yellow { color: #fde68a; }

/* ----------------------------------------
   Shared data table (nuances, comparisons)
   ---------------------------------------- */
.table-wrapper {
  overflow-x: auto;
  margin: 28px 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--glass-border);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  min-width: 420px;
}

.data-table thead {
  background: rgba(79, 195, 247, 0.06);
}

.data-table th {
  padding: 13px 18px;
  text-align: left;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--blue-accent);
  border-bottom: 1px solid var(--glass-border);
  white-space: nowrap;
}

.data-table td {
  padding: 14px 18px;
  color: var(--text-secondary);
  line-height: 1.6;
  border-bottom: 1px solid rgba(79, 195, 247, 0.06);
  vertical-align: top;
}

.data-table tbody tr:last-child td { border-bottom: none; }
.data-table tbody tr:hover td { background: rgba(79, 195, 247, 0.03); }
.data-table td strong { color: var(--text-primary); font-weight: 600; }
.data-table td code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  color: var(--blue-accent);
  background: rgba(79, 195, 247, 0.08);
  border: 1px solid rgba(79, 195, 247, 0.15);
  border-radius: 4px;
  padding: 1px 6px;
}

/* ----------------------------------------
   Module nav row (prev / next)
   ---------------------------------------- */
.module-nav-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-top: 48px;
  border-top: 1px solid var(--glass-border);
  flex-wrap: wrap;
}

.module-nav-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 22px;
  border-radius: var(--radius-md);
  border: 1px solid var(--glass-border);
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 600;
  text-decoration: none;
  transition: border-color 0.2s, color 0.2s, transform 0.15s;
}

.module-nav-btn:hover {
  border-color: rgba(79, 195, 247, 0.3);
  color: var(--text-primary);
  transform: translateY(-2px);
}

.module-nav-btn--next { margin-left: auto; }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 960px) {
  .module-page-layout {
    flex-direction: column;
    padding: 88px 20px 60px;
  }

  .progress-sidebar {
    position: static;
    width: 100%;
    max-height: none;
    padding: 14px 16px;
    overflow: visible;
  }

  .sidebar-nav {
    flex-direction: row;
    flex-wrap: nowrap;
    overflow-x: auto;
    gap: 6px;
    padding-bottom: 4px;
    scrollbar-width: none;
  }

  .sidebar-nav::-webkit-scrollbar { display: none; }

  .sidebar-link {
    flex-shrink: 0;
    white-space: nowrap;
    border-left: none;
    border-bottom: 2px solid transparent;
    border-radius: var(--radius-sm);
    padding: 6px 14px;
    font-size: 0.8rem;
  }

  .sidebar-link.active {
    border-left: none;
    border-bottom-color: var(--blue-accent);
    background: rgba(79, 195, 247, 0.08);
  }

  .sidebar-dot { display: none; }

  .module-main { max-width: 100%; }
}

@media (max-width: 600px) {
  .module-page-layout {
    padding: 80px 16px 48px;
  }

  .module-hero-title { font-size: 1.75rem; }

  .diagram-container {
    padding: 28px 16px;
    min-height: 200px;
  }

  .diagram-container .mermaid svg {
    max-width: 100%;
    min-height: 160px;
  }

  .module-nav-row {
    flex-direction: column;
    align-items: stretch;
  }

  .module-nav-btn { justify-content: center; }
  .module-nav-btn--next { margin-left: 0; }

  .tf-options { flex-direction: column; }
}