/* ==========================================================================
   TOPCIT Study Reviewer Stylesheet - Module 01 Software Development
   Optimized for mobile phones, tablets, and desktop study sessions
   ========================================================================== */

:root {
  --rev-ink: #0f1e29;
  --rev-muted: #536978;
  --rev-surface: #ffffff;
  --rev-surface-alt: #f4f8fa;
  --rev-border: #d4e1e8;
  --rev-border-light: #e6eef2;
  --rev-brand: #102b3f;
  --rev-brand-light: #1b4564;
  --rev-accent: #00877d;
  --rev-accent-light: #e0f4f2;
  --rev-accent-border: #a4ded8;
  --rev-accent-hover: #006b63;
  --rev-warning: #9a6700;
  --rev-warning-bg: #fff8e6;
  --rev-warning-border: #f0cf7e;
  --rev-success: #197a47;
  --rev-success-bg: #eafaf1;
  --rev-success-border: #9ce2b9;
  --rev-danger: #cf222e;
  --rev-danger-bg: #ffebe9;
  --rev-danger-border: #ff8182;
  --rev-radius-sm: 6px;
  --rev-radius-md: 10px;
  --rev-radius-lg: 16px;
  --rev-shadow-sm: 0 1px 3px rgba(16, 43, 63, 0.08);
  --rev-shadow-md: 0 4px 14px rgba(16, 43, 63, 0.1);
  --rev-shadow-lg: 0 10px 28px rgba(16, 43, 63, 0.14);
}

#toggle-reviewer-btn,
.display-controls #toggle-reviewer-btn {
  display: inline-flex !important;
  align-items: center;
  justify-content: center;
  font-family: inherit;
  font-size: 0.82rem;
  font-weight: 700;
  color: #102b3f !important;
  background: #25c2b4 !important;
  border: 1px solid #1ba599 !important;
  border-radius: 0.35rem;
  padding: 0.45rem 0.85rem;
  white-space: nowrap;
  cursor: pointer;
  transition: all 140ms ease;
  min-height: 2.25rem;
  text-decoration: none;
}

#toggle-reviewer-btn:hover,
.display-controls #toggle-reviewer-btn:hover {
  background: #52d3c8 !important;
  border-color: #52d3c8 !important;
  color: #0c2030 !important;
}

/* When Study Reviewer is active, hide the top navbar reader controls and redundant toggle button */
.reader.reviewer-active #toggle-reviewer-btn,
.reader.reviewer-active .display-controls #toggle-reviewer-btn,
.reader.reviewer-active #sidebar-toggle,
.reader.reviewer-active .page-controls,
.reader.reviewer-active .zoom-controls,
.reader.reviewer-active #fit-page,
.reader.reviewer-active #fit-width,
.reader.reviewer-active #fullscreen {
  display: none !important;
}


.back-to-pdf-bar-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.45rem 0.95rem;
  font-size: 0.84rem;
  font-weight: 700;
  color: #102b3f;
  background: #25c2b4;
  border: 1px solid #1ba599;
  border-radius: 999px;
  cursor: pointer;
  transition: all 140ms ease;
  white-space: nowrap;
}

.back-to-pdf-bar-btn:hover {
  background: #52d3c8;
  border-color: #52d3c8;
}

.back-to-pdf-bar-btn svg {
  width: 1rem;
  height: 1rem;
  fill: currentColor;
}

.view-mode-tab {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.4rem 0.85rem;
  font-size: 0.84rem;
  font-weight: 600;
  color: #d4e5f0;
  background: transparent;
  border: none;
  border-radius: 999px;
  cursor: pointer;
  transition: all 150ms ease;
  white-space: nowrap;
}

.view-mode-tab:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.08);
}

.view-mode-tab.is-active {
  color: #102b3f;
  background: #25c2b4;
  font-weight: 700;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
}

.view-mode-tab svg {
  width: 1rem;
  height: 1rem;
  fill: currentColor;
  flex-shrink: 0;
}

/* ==========================================================================
   Main Reviewer Container
   ========================================================================== */
.study-reviewer-view {
  display: flex;
  flex-direction: column;
  height: calc(100dvh - var(--toolbar-height));
  background: #eaf1f5;
  overflow: hidden;
  position: relative;
}

.study-reviewer-view[hidden] {
  display: none !important;
}

/* Sub-header Bar */
.reviewer-header-bar {
  background: var(--rev-surface);
  border-bottom: 1px solid var(--rev-border);
  padding: 0.75rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-shrink: 0;
  box-shadow: var(--rev-shadow-sm);
  z-index: 10;
}

.reviewer-stats {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.88rem;
  color: var(--rev-muted);
}

.reviewer-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: var(--rev-accent-light);
  color: var(--rev-accent);
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 700;
  border: 1px solid var(--rev-accent-border);
}

.reviewer-search-wrap {
  position: relative;
  max-width: 320px;
  width: 100%;
}

.reviewer-search-input {
  width: 100%;
  padding: 0.45rem 0.85rem 0.45rem 2.2rem;
  font-size: 0.88rem;
  border: 1px solid var(--rev-border);
  border-radius: 999px;
  background: var(--rev-surface-alt);
  color: var(--rev-ink);
  outline: none;
  transition: border-color 150ms ease, box-shadow 150ms ease, background 150ms ease;
}

.reviewer-search-input:focus {
  background: #ffffff;
  border-color: var(--rev-accent);
  box-shadow: 0 0 0 3px rgba(0, 135, 125, 0.15);
}

.reviewer-search-icon {
  position: absolute;
  left: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1rem;
  height: 1rem;
  fill: var(--rev-muted);
  pointer-events: none;
}

/* Mobile Quick Topic Jump Bar */
.mobile-topic-bar {
  display: none;
  background: #ffffff;
  padding: 0.5rem 0.75rem;
  border-bottom: 1px solid var(--rev-border);
  gap: 0.5rem;
  align-items: center;
  flex-shrink: 0;
}

.mobile-topic-select {
  flex: 1;
  padding: 0.5rem 0.75rem;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--rev-ink);
  background: var(--rev-surface-alt);
  border: 1px solid var(--rev-border);
  border-radius: var(--rev-radius-sm);
  outline: none;
}

/* Two-column Reviewer Layout */
.reviewer-layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  flex: 1;
  min-height: 0;
  overflow: hidden;
}

/* Sidebar: Topics List */
.reviewer-topics-sidebar {
  background: #ffffff;
  border-right: 1px solid var(--rev-border);
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  -webkit-overflow-scrolling: touch;
}

.sidebar-section-title {
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--rev-muted);
  padding: 1rem 1rem 0.5rem;
}

.reviewer-topic-nav-list {
  list-style: none;
  margin: 0;
  padding: 0 0.5rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.reviewer-nav-btn {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  width: 100%;
  padding: 0.65rem 0.75rem;
  background: transparent;
  border: none;
  border-radius: var(--rev-radius-sm);
  color: var(--rev-ink);
  font-size: 0.85rem;
  font-weight: 550;
  text-align: left;
  cursor: pointer;
  transition: all 140ms ease;
  line-height: 1.35;
}

.reviewer-nav-btn:hover {
  background: var(--rev-surface-alt);
  color: var(--rev-accent);
}

.reviewer-nav-btn.is-active {
  background: var(--rev-accent-light);
  color: var(--rev-accent);
  font-weight: 700;
  border-left: 3px solid var(--rev-accent);
}

.reviewer-nav-num {
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--rev-muted);
  background: var(--rev-surface-alt);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  flex-shrink: 0;
}

.reviewer-nav-btn.is-active .reviewer-nav-num {
  background: var(--rev-accent);
  color: #ffffff;
}

/* Main Content Area */
.reviewer-content-stage {
  overflow-y: auto;
  padding: 1.5rem 2rem 5rem;
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
}

.reviewer-inner-wrap {
  max-width: 860px;
  margin: 0 auto;
}

/* Topic Card */
.topic-card {
  background: #ffffff;
  border: 1px solid var(--rev-border);
  border-radius: var(--rev-radius-lg);
  padding: 2rem 2.25rem;
  margin-bottom: 2.25rem;
  box-shadow: var(--rev-shadow-sm);
  transition: box-shadow 180ms ease;
}

.topic-card:hover {
  box-shadow: var(--rev-shadow-md);
}

.topic-header {
  border-bottom: 2px solid var(--rev-border-light);
  padding-bottom: 1.25rem;
  margin-bottom: 1.5rem;
}

.topic-meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 0.65rem;
}

.topic-badge-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.topic-num-badge {
  background: var(--rev-brand);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  letter-spacing: 0.04em;
}

.topic-pages-badge {
  background: var(--rev-surface-alt);
  color: var(--rev-muted);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  border: 1px solid var(--rev-border);
}

.jump-to-pdf-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.8rem;
  font-weight: 650;
  color: var(--rev-accent);
  background: var(--rev-accent-light);
  border: 1px solid var(--rev-accent-border);
  padding: 0.3rem 0.75rem;
  border-radius: 999px;
  cursor: pointer;
  transition: all 140ms ease;
  text-decoration: none;
}

.jump-to-pdf-btn:hover {
  background: var(--rev-accent);
  color: #ffffff;
}

.jump-to-pdf-btn svg {
  width: 0.9rem;
  height: 0.9rem;
  fill: currentColor;
}

.topic-title {
  margin: 0.25rem 0 0.5rem;
  font-size: 1.6rem;
  font-weight: 750;
  color: var(--rev-ink);
  line-height: 1.3;
}

.topic-lead {
  font-size: 1.02rem;
  color: var(--rev-muted);
  line-height: 1.6;
  margin: 0;
}

/* Sections & Typography */
.subtopic-block {
  margin-top: 1.8rem;
}

.subtopic-title {
  font-size: 1.22rem;
  font-weight: 700;
  color: var(--rev-brand);
  margin: 0 0 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.subtopic-title::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 1.1rem;
  background: var(--rev-accent);
  border-radius: 2px;
}

.subtopic-text {
  font-size: 0.98rem;
  line-height: 1.68;
  color: #2a3c48;
  margin: 0 0 1rem;
}

/* Key Callout Box */
.callout-box {
  background: var(--rev-surface-alt);
  border-left: 4px solid var(--rev-accent);
  border-radius: 0 var(--rev-radius-sm) var(--rev-radius-sm) 0;
  padding: 1rem 1.25rem;
  margin: 1.25rem 0;
}

.callout-box.exam-tip {
  background: var(--rev-warning-bg);
  border-left-color: var(--rev-warning);
}

.callout-title {
  font-size: 0.85rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--rev-accent);
  margin-bottom: 0.35rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.callout-box.exam-tip .callout-title {
  color: var(--rev-warning);
}

.callout-body {
  font-size: 0.92rem;
  line-height: 1.6;
  color: #233440;
  margin: 0;
}

/* High-yield Tables */
.table-scroll-container {
  overflow-x: auto;
  margin: 1.25rem 0 1.5rem;
  border: 1px solid var(--rev-border);
  border-radius: var(--rev-radius-md);
  -webkit-overflow-scrolling: touch;
}

.reviewer-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  text-align: left;
  background: #ffffff;
}

.reviewer-table th {
  background: #f1f6f9;
  color: var(--rev-brand);
  font-weight: 750;
  padding: 0.75rem 1rem;
  border-bottom: 2px solid var(--rev-border);
  white-space: nowrap;
}

.reviewer-table td {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--rev-border-light);
  color: #2b3d49;
  line-height: 1.5;
  vertical-align: top;
}

.reviewer-table tr:last-child td {
  border-bottom: none;
}

.reviewer-table tr:nth-child(even) {
  background: #fcfdfe;
}

/* Bullet list & Concept pills */
.key-points-list {
  margin: 0.75rem 0 1.25rem;
  padding-left: 1.35rem;
}

.key-points-list li {
  font-size: 0.95rem;
  line-height: 1.65;
  color: #273844;
  margin-bottom: 0.45rem;
}

.concept-pill-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0.85rem 0;
}

.concept-pill {
  font-size: 0.8rem;
  font-weight: 600;
  background: #edf3f7;
  color: #17364d;
  padding: 0.3rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--rev-border);
}

/* Diagrams and Flowcharts */
.diagram-block {
  background: #0d1e29;
  color: #a8dfd6;
  font-family: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 0.82rem;
  line-height: 1.45;
  padding: 1.15rem;
  border-radius: var(--rev-radius-md);
  overflow-x: auto;
  margin: 1.25rem 0;
  white-space: pre;
  border: 1px solid #20435a;
}

/* ==========================================================================
   Practice Quiz Components
   ========================================================================== */
.quiz-section {
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 2px dashed var(--rev-border);
}

.quiz-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.25rem;
}

.quiz-title {
  font-size: 1.15rem;
  font-weight: 750;
  color: var(--rev-ink);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
}

.quiz-counter {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--rev-muted);
  background: var(--rev-surface-alt);
  padding: 0.2rem 0.55rem;
  border-radius: 999px;
  border: 1px solid var(--rev-border);
}

.quiz-item-card {
  background: var(--rev-surface-alt);
  border: 1px solid var(--rev-border);
  border-radius: var(--rev-radius-md);
  padding: 1.25rem;
  margin-bottom: 1rem;
}

.quiz-question-text {
  font-size: 0.98rem;
  font-weight: 650;
  color: var(--rev-ink);
  line-height: 1.55;
  margin: 0 0 1rem;
}

.quiz-options-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.quiz-option-btn {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  width: 100%;
  padding: 0.75rem 1rem;
  min-height: 48px; /* Touch-friendly */
  background: #ffffff;
  border: 1.5px solid var(--rev-border);
  border-radius: var(--rev-radius-sm);
  color: var(--rev-ink);
  font-size: 0.92rem;
  line-height: 1.45;
  text-align: left;
  cursor: pointer;
  transition: all 120ms ease;
  user-select: none;
}

.quiz-option-btn:hover:not(:disabled) {
  border-color: var(--rev-accent);
  background: #fafdfe;
  transform: translateY(-1px);
}

.quiz-opt-letter {
  display: grid;
  place-items: center;
  width: 1.45rem;
  height: 1.45rem;
  border-radius: 50%;
  background: #eef3f7;
  color: var(--rev-brand);
  font-size: 0.78rem;
  font-weight: 800;
  flex-shrink: 0;
  margin-top: 1px;
}

.quiz-option-btn.is-correct {
  background: var(--rev-success-bg) !important;
  border-color: var(--rev-success) !important;
  color: #0d4e2a !important;
  font-weight: 650;
}

.quiz-option-btn.is-correct .quiz-opt-letter {
  background: var(--rev-success);
  color: #ffffff;
}

.quiz-option-btn.is-wrong {
  background: var(--rev-danger-bg) !important;
  border-color: var(--rev-danger) !important;
  color: #791a22 !important;
}

.quiz-option-btn.is-wrong .quiz-opt-letter {
  background: var(--rev-danger);
  color: #ffffff;
}

.quiz-explanation-box {
  margin-top: 0.9rem;
  padding: 0.85rem 1rem;
  border-radius: var(--rev-radius-sm);
  background: #ffffff;
  border: 1px solid var(--rev-border);
  font-size: 0.88rem;
  line-height: 1.55;
  color: #2d414e;
  display: none;
}

.quiz-explanation-box.is-visible {
  display: block;
  animation: fadeIn 180ms ease;
}

.quiz-explanation-box strong {
  color: var(--rev-accent);
  display: block;
  margin-bottom: 0.25rem;
}

/* Floating Return to Top Button (Mobile) */
.reviewer-floating-top {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 30;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.65rem 1.15rem;
  background: var(--rev-brand);
  color: #ffffff;
  font-size: 0.82rem;
  font-weight: 700;
  border: none;
  border-radius: 999px;
  box-shadow: var(--rev-shadow-lg);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: all 180ms ease;
}

.reviewer-floating-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.reviewer-floating-top:hover {
  background: var(--rev-brand-light);
  transform: translateY(-2px);
}

.reviewer-floating-top svg {
  width: 0.95rem;
  height: 0.95rem;
  fill: #25c2b4;
}

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

/* ==========================================================================
   Mobile-First Responsive Adjustments (< 768px)
   ========================================================================== */
@media (max-width: 768px) {
  .study-reviewer-view {
    height: calc(100dvh - var(--toolbar-height));
  }

  .reviewer-header-bar {
    padding: 0.55rem 0.85rem;
    flex-wrap: wrap;
    gap: 0.5rem;
  }

  .reviewer-stats {
    width: 100%;
    justify-content: flex-start;
    gap: 0.4rem;
    flex-wrap: wrap;
  }

  .reviewer-badge {
    font-size: 0.72rem;
    padding: 0.2rem 0.5rem;
  }

  .reviewer-search-wrap {
    max-width: 100%;
    order: 3;
  }

  .reviewer-search-input {
    font-size: 16px; /* Prevents auto-zoom on iOS */
    padding: 0.5rem 0.85rem 0.5rem 2.2rem;
  }

  .mobile-topic-bar {
    display: flex;
    padding: 0.45rem 0.75rem;
  }

  .mobile-topic-select {
    font-size: 16px; /* Prevents auto-zoom on iOS */
    padding: 0.55rem 0.75rem;
  }

  .reviewer-layout {
    grid-template-columns: 1fr;
  }

  .reviewer-topics-sidebar {
    display: none; /* Hidden on mobile; use top quick-jump dropdown instead */
  }

  .reviewer-content-stage {
    padding: 1rem 0.75rem 6rem;
  }

  .topic-card {
    padding: 1.25rem 0.95rem;
    border-radius: var(--rev-radius-md);
    margin-bottom: 1.5rem;
  }

  .topic-title {
    font-size: 1.3rem;
  }

  .topic-lead {
    font-size: 0.92rem;
  }

  .subtopic-title {
    font-size: 1.05rem;
  }

  .subtopic-text {
    font-size: 0.93rem;
    line-height: 1.62;
  }

  .quiz-option-btn {
    padding: 0.8rem 0.9rem;
    font-size: 0.9rem;
  }

  .diagram-block {
    font-size: 0.7rem;
    padding: 0.85rem;
  }

  .view-mode-tabs {
    padding: 2px;
  }

  .view-mode-tab {
    padding: 0.35rem 0.6rem;
    font-size: 0.76rem;
    gap: 0.3rem;
  }

  .reviewer-floating-top {
    bottom: 1rem;
    right: 1rem;
    padding: 0.55rem 0.95rem;
    font-size: 0.78rem;
  }
}

@media (max-width: 480px) {
  .topic-meta-row {
    flex-direction: column;
    align-items: flex-start;
  }

  .jump-to-pdf-btn {
    width: 100%;
    justify-content: center;
    padding: 0.45rem;
  }

  .view-mode-tab svg {
    display: none; /* Keep text clean on very narrow screens */
  }
}