/**
 * IELTS Cinematic Task 1 Visual Knowledge Studio — Stylesheet (v1.0 Cinema Edition)
 * English Mastery Hub • Visual Data Dynamics, Trend Physics & Preposition Mechanics
 *
 * Taste-Skill Dial Calibration:
 * - DESIGN_VARIANCE: 8 (High visual distinction, neon graph curves, laser sweep animations, dark glassmorphism)
 * - MOTION_INTENSITY: 8 (Smooth 60fps Chart.js canvas rendering, radar crosshairs, particle trails, 3D card flips)
 * - VISUAL_DENSITY: 3 (Spacious full-screen cinema canvas for zero cognitive clutter)
 */

@import url('https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:ital,wght@0,300;0,400;0,500;0,600;0,700;0,800;1,400;1,600&family=Plus+Jakarta+Sans:ital,wght@0,400;0,500;0,600;0,700;0,800;1,400;1,600&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
  /* Surface Foundations */
  --bg-deep: #080c12;
  --bg-theater: #0c1017;
  --bg-card: rgba(18, 24, 32, 0.85);
  --bg-card-hover: rgba(28, 36, 48, 0.95);
  --bg-overlay: rgba(8, 12, 18, 0.9);
  --bg-glass: rgba(255, 255, 255, 0.05);
  --bg-glass-active: rgba(255, 255, 255, 0.12);

  /* Borders & Highlights */
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-focus: rgba(255, 255, 255, 0.24);
  --border-card: rgba(255, 255, 255, 0.12);

  /* Typography: Flawless Vietnamese Subsets */
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --font-display: 'Plus Jakarta Sans', 'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Be Vietnam Pro', 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Neon Spectral Coding */
  --neon-cyan: #38bdf8;
  --neon-cyan-glow: rgba(56, 189, 248, 0.35);
  --neon-cyan-bg: rgba(56, 189, 248, 0.12);

  --neon-amber: #f59e0b;
  --neon-amber-glow: rgba(245, 158, 11, 0.35);
  --neon-amber-bg: rgba(245, 158, 11, 0.12);

  --neon-purple: #c084fc;
  --neon-purple-glow: rgba(192, 132, 252, 0.35);
  --neon-purple-bg: rgba(192, 132, 252, 0.12);

  --neon-emerald: #34d399;
  --neon-emerald-glow: rgba(52, 211, 153, 0.35);
  --neon-emerald-bg: rgba(52, 211, 153, 0.12);

  --neon-rose: #f43f5e;
  --neon-rose-glow: rgba(244, 63, 94, 0.35);
  --neon-rose-bg: rgba(244, 63, 94, 0.12);

  /* Preposition Physics Hues */
  --color-by: #f43f5e;     /* Red difference bracket */
  --color-to: #10b981;     /* Green endpoint flag */
  --color-at: #facc15;     /* Yellow status anchor pin */

  /* Dimensions & Physics */
  --radius-card: 20px;
  --radius-pill: 9999px;
  --transition-fluid: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-bounce: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html, body {
  width: 100%;
  min-height: 100dvh;
  background-color: var(--bg-deep);
  color: var(--text-main);
  font-family: var(--font-body);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Atmospheric Backdrop & Letterbox Vignettes */
.cinematic-backdrop {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}

.backdrop-img {
  position: absolute;
  inset: -30px;
  background-size: cover;
  background-position: center 25%;
  filter: blur(36px) brightness(0.2) saturate(1.3);
  transform: scale(1.12);
  transition: opacity 0.8s ease;
}

.backdrop-gradient {
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 50% 15%, var(--neon-cyan-glow), transparent 60%),
              radial-gradient(circle at 80% 85%, var(--neon-purple-glow), transparent 50%),
              linear-gradient(to bottom, rgba(8, 12, 18, 0.78), rgba(8, 12, 18, 0.98));
}

.cinema-letterbox-top {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 75px;
  background: linear-gradient(to bottom, rgba(0, 0, 0, 0.85), transparent);
}

.cinema-letterbox-bottom {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 85px;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.9), transparent);
}

/* Main Application Shell */
.cinematic-app {
  position: relative;
  z-index: 1;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

/* Top Glassmorphic Navigation Bar */
.cinematic-nav {
  position: sticky;
  top: 0;
  z-index: 60;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 1.75rem;
  background: rgba(12, 16, 23, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  gap: 1rem;
}

.nav-left {
  display: flex;
  align-items: center;
  gap: 1rem;
  min-width: 0;
}

.btn-nav-back {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.45rem 0.95rem;
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--text-muted);
  background: var(--bg-glass);
  border: 1px solid var(--border-subtle);
  border-radius: 9px;
  text-decoration: none;
  transition: var(--transition-fluid);
  cursor: pointer;
  white-space: nowrap;
  flex-shrink: 0;
}

.btn-nav-back:hover {
  color: var(--text-main);
  background: var(--bg-glass-active);
  border-color: var(--border-focus);
  transform: translateX(-2px);
}

.nav-passage-title {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-display);
  min-width: 0;
}

.passage-tag {
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 0.22rem 0.65rem;
  border-radius: 6px;
  background: var(--neon-cyan-bg);
  color: var(--neon-cyan);
  border: 1px solid var(--neon-cyan-glow);
  white-space: nowrap;
}

.passage-heading {
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
  white-space: nowrap;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
}

.btn-theater-action {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.45rem 0.85rem;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  background: var(--bg-glass);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: var(--transition-fluid);
  white-space: nowrap;
}

.btn-theater-action:hover {
  color: var(--text-main);
  background: var(--bg-glass-active);
  border-color: var(--border-focus);
}

.btn-theater-action.active {
  color: #fff;
  background: var(--neon-cyan-bg);
  border-color: var(--neon-cyan);
  box-shadow: 0 0 16px var(--neon-cyan-glow);
}

.btn-theater-practice {
  background: linear-gradient(135deg, #0284c7, #2563eb);
  color: #fff;
  border-color: rgba(56, 189, 248, 0.4);
  text-decoration: none;
}

.btn-theater-practice:hover {
  background: linear-gradient(135deg, #0369a1, #1d4ed8);
  box-shadow: 0 0 20px rgba(37, 99, 235, 0.45);
  transform: translateY(-1px);
}

/* 4-Module Mode Selector Header */
.cinematic-mode-track {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 2rem;
  background: rgba(8, 12, 18, 0.65);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-subtle);
  gap: 1rem;
  overflow-x: auto;
}

.mode-tabs-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: nowrap;
}

.btn-mode-tab {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.5rem 1.15rem;
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: var(--transition-fluid);
  white-space: nowrap;
}

.btn-mode-tab:hover {
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.08);
  border-color: var(--border-focus);
}

.btn-mode-tab.active {
  color: #fff;
  background: var(--neon-cyan-bg);
  border-color: var(--neon-cyan);
  box-shadow: 0 0 16px var(--neon-cyan-glow);
}

/* Main Workspace Stage */
.cinematic-main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem 2.5rem 6.5rem;
  position: relative;
  min-height: calc(100dvh - 140px);
}

/* ==========================================================================
   MODULE 1: RADAR OVERVIEW SCANNER STAGE
   ========================================================================== */
.radar-stage-container {
  width: 100%;
  max-width: 1100px;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  animation: stageIn 0.4s ease forwards;
}

@keyframes stageIn {
  from { opacity: 0; transform: scale(0.98); }
  to { opacity: 1; transform: scale(1); }
}

.radar-canvas-card {
  background: var(--bg-card);
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-card);
  padding: 2.25rem 2.75rem;
  box-shadow: 0 25px 70px rgba(0, 0, 0, 0.7);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  position: relative;
  overflow: hidden;
}

.radar-header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}

.radar-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-display);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--neon-purple);
  background: var(--neon-purple-bg);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--neon-purple-glow);
}

.radar-viewport {
  position: relative;
  width: 100%;
  height: 360px;
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--border-subtle);
  border-radius: 16px;
  overflow: hidden;
}

/* Radar Laser Beam Sweep */
.radar-laser-beam {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--neon-cyan);
  box-shadow: 0 0 20px var(--neon-cyan), 0 0 40px var(--neon-cyan);
  pointer-events: none;
  left: 0%;
  transition: left 0.05s linear;
  display: none;
}

.radar-laser-beam.active {
  display: block;
  animation: laserSweep 3s cubic-bezier(0.4, 0, 0.2, 1) infinite alternate;
}

@keyframes laserSweep {
  0% { left: 5%; }
  100% { left: 95%; }
}

/* Radar Target Lock Rings & Tactical Crosshairs */
.radar-target-lock {
  position: absolute;
  width: 38px;
  height: 38px;
  border: 2px solid var(--neon-amber);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
  box-shadow: 0 0 20px var(--neon-amber), inset 0 0 10px rgba(245, 158, 11, 0.4);
  animation: pulseLock 1.6s ease-in-out infinite;
  display: none;
  z-index: 10;
  transition: opacity 0.3s ease;
}

.radar-target-lock::before,
.radar-target-lock::after {
  content: '';
  position: absolute;
  background: var(--neon-amber);
  opacity: 0.85;
}

.radar-target-lock::before {
  top: 50%;
  left: -8px;
  right: -8px;
  height: 1.5px;
  transform: translateY(-50%);
}

.radar-target-lock::after {
  left: 50%;
  top: -8px;
  bottom: -8px;
  width: 1.5px;
  transform: translateX(-50%);
}

.radar-target-lock.radar-lock-cyan {
  border-color: var(--neon-cyan);
  box-shadow: 0 0 20px var(--neon-cyan), inset 0 0 10px rgba(56, 189, 248, 0.4);
}

.radar-target-lock.radar-lock-cyan::before,
.radar-target-lock.radar-lock-cyan::after {
  background: var(--neon-cyan);
}

.radar-target-lock.active {
  display: block;
}

@keyframes pulseLock {
  0% { transform: translate(-50%, -50%) scale(0.92); opacity: 0.85; }
  50% { transform: translate(-50%, -50%) scale(1.18); opacity: 1; }
  100% { transform: translate(-50%, -50%) scale(0.92); opacity: 0.85; }
}

/* Radar Output Sentence Cards */
.radar-sentence-output-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
}

.radar-sentence-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 1.25rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  transition: var(--transition-fluid);
}

.radar-sentence-card.highlight-cyan {
  border-color: rgba(56, 189, 248, 0.35);
  background: rgba(56, 189, 248, 0.05);
}

.radar-sentence-card.highlight-amber {
  border-color: rgba(245, 158, 11, 0.35);
  background: rgba(245, 158, 11, 0.05);
}

.radar-card-label {
  font-family: var(--font-display);
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.radar-card-text {
  font-size: 0.98rem;
  line-height: 1.55;
  color: #fff;
  font-weight: 500;
}

/* ==========================================================================
   MODULE 2: LIVE MOTION CURVES & TREND PHYSICS LAB
   ========================================================================== */
.trend-stage-container {
  width: 100%;
  max-width: 1100px;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  animation: stageIn 0.4s ease forwards;
}

.trend-buttons-carousel {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  overflow-x: auto;
  padding-bottom: 0.35rem;
}

.btn-trend-motion {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.55rem 1rem;
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-muted);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  cursor: pointer;
  transition: var(--transition-fluid);
  white-space: nowrap;
}

.btn-trend-motion:hover {
  color: var(--text-main);
  background: var(--bg-card-hover);
  border-color: var(--border-focus);
}

.btn-trend-motion.active {
  color: #fff;
  background: var(--neon-cyan-bg);
  border-color: var(--neon-cyan);
  box-shadow: 0 0 16px var(--neon-cyan-glow);
}

.trend-canvas-hero-box {
  background: var(--bg-card);
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-card);
  padding: 2.5rem 3rem;
  box-shadow: 0 25px 70px rgba(0, 0, 0, 0.7);
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
  min-height: 420px;
}

/* Synchronized 4-Structure Sentence Anatomy */
.anatomy-structures-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.anatomy-structure-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 1.15rem;
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  transition: var(--transition-fluid);
}

.anatomy-structure-card:hover {
  background: rgba(255, 255, 255, 0.06);
  border-color: var(--border-focus);
}

.anatomy-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--neon-cyan);
}

.anatomy-sentence {
  font-size: 0.95rem;
  line-height: 1.55;
  color: #f1f5f9;
}

/* Token Highlights */
.tok-sub { color: #38bdf8; font-weight: 700; }
.tok-v { color: #facc15; font-weight: 700; }
.tok-adv { color: #34d399; font-weight: 700; }
.tok-prep { color: #f43f5e; font-weight: 700; }
.tok-data { color: #c084fc; font-weight: 700; }

/* ==========================================================================
   MODULE 3: PREPOSITION DYNAMIC RULER (BY vs TO vs AT)
   ========================================================================== */
.prep-stage-container {
  width: 100%;
  max-width: 1100px;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  animation: stageIn 0.4s ease forwards;
}

.prep-ruler-card {
  background: var(--bg-card);
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-card);
  padding: 2.75rem 3rem;
  box-shadow: 0 25px 70px rgba(0, 0, 0, 0.7);
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

/* Noun Mode Switcher & Grammar Rules */
.noun-mode-switcher-wrap {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.noun-mode-switcher {
  display: flex;
  gap: 0.85rem;
  flex-wrap: wrap;
}

.btn-noun-tab {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.65rem 1.25rem;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
  color: var(--text-muted);
  font-family: var(--font-display);
  font-size: 0.88rem;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition-fluid);
}

.btn-noun-tab:hover {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  border-color: var(--border-focus);
}

.btn-noun-tab.active {
  background: rgba(16, 185, 129, 0.15);
  border-color: var(--color-to);
  color: #fff;
  box-shadow: 0 0 16px rgba(16, 185, 129, 0.25);
}

.noun-grammar-note {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  padding: 0.75rem 1.15rem;
  background: rgba(56, 189, 248, 0.08);
  border: 1px solid rgba(56, 189, 248, 0.25);
  border-radius: 10px;
  font-size: 0.86rem;
  color: #bae6fd;
  line-height: 1.5;
}

.noun-grammar-note i {
  color: var(--neon-cyan);
  font-size: 1rem;
}

.ruler-track-container {
  position: relative;
  width: 100%;
  height: 90px;
  background: rgba(0, 0, 0, 0.4);
  border-radius: 14px;
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  padding: 0 2rem;
}

.ruler-axis-line {
  position: relative;
  width: 100%;
  height: 6px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 9999px;
}

/* Bracket "BY" (Difference Span) */
.bracket-by-span {
  position: absolute;
  height: 36px;
  top: -45px;
  border-left: 2px solid var(--color-by);
  border-right: 2px solid var(--color-by);
  border-top: 2px dashed var(--color-by);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-by);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 700;
  transition: all 0.1s linear;
}

/* Pin "AT" (Start) */
.pin-start-at {
  position: absolute;
  top: -12px;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--color-at);
  transform: translate(-50%, -50%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #080c12;
  font-weight: 800;
  font-size: 0.75rem;
  box-shadow: 0 0 16px var(--color-at);
  cursor: grab;
}

/* Flag "TO" (Endpoint) */
.flag-end-to {
  position: absolute;
  top: -12px;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--color-to);
  transform: translate(-50%, -50%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #080c12;
  font-weight: 800;
  font-size: 0.75rem;
  box-shadow: 0 0 16px var(--color-to);
  cursor: grab;
}

.prep-explanation-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

.prep-explanation-box {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.prep-explanation-box.box-by { border-left: 4px solid var(--color-by); }
.prep-explanation-box.box-to { border-left: 4px solid var(--color-to); }
.prep-explanation-box.box-at { border-left: 4px solid var(--color-at); }

.prep-box-title {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 800;
}

.prep-box-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.prep-box-formula {
  background: rgba(0, 0, 0, 0.3);
  padding: 0.65rem 0.85rem;
  border-radius: 8px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: #fff;
}

/* ==========================================================================
   MODULE 4: STATIC RATIO & PIE ARENA
   ========================================================================== */
.static-stage-container {
  width: 100%;
  max-width: 1100px;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  animation: stageIn 0.4s ease forwards;
}

.static-pie-card {
  background: var(--bg-card);
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-card);
  padding: 2.5rem 3rem;
  box-shadow: 0 25px 70px rgba(0, 0, 0, 0.7);
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.static-pie-split-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  align-items: center;
}

.pie-visual-container {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 320px;
}

.ratios-list-card {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.ratio-item {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  transition: var(--transition-fluid);
}

.ratio-item:hover,
.ratio-item.active {
  background: rgba(245, 158, 11, 0.12);
  border-color: var(--neon-amber);
}

.ratio-left {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.ratio-fraction-name {
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
}

.ratio-percentage-range {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
}

.ratio-multiplier-pill {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--neon-amber);
  background: var(--neon-amber-bg);
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-pill);
}

/* Pie Slice Modal & Interactive Pop-up */
.pie-slice-modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 100;
  background: rgba(8, 12, 18, 0.78);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  animation: modalFadeIn 0.25s ease forwards;
}

@keyframes modalFadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.pie-slice-modal-card {
  width: 100%;
  max-width: 580px;
  background: #0f1523;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 18px;
  box-shadow: 0 30px 90px rgba(0, 0, 0, 0.8), 0 0 40px rgba(245, 158, 11, 0.15);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  animation: modalCardPop 0.3s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes modalCardPop {
  from { transform: scale(0.92) translateY(12px); opacity: 0; }
  to { transform: scale(1) translateY(0); opacity: 1; }
}

.pie-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.35rem 1.75rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(255, 255, 255, 0.02);
}

.pie-modal-color-dot {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  flex-shrink: 0;
}

.pie-modal-title {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 800;
  color: #fff;
  margin: 0;
}

.pie-modal-subtitle {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--neon-amber);
  margin-top: 0.15rem;
}

.btn-close-modal {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition-fluid);
}

.btn-close-modal:hover {
  background: rgba(244, 63, 94, 0.2);
  border-color: var(--neon-rose);
  color: #fff;
}

.pie-modal-body {
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.pie-collocation-box,
.pie-sentence-box {
  background: rgba(0, 0, 0, 0.35);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 12px;
  padding: 1.15rem 1.35rem;
}

.pie-section-label {
  font-family: var(--font-display);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.45rem;
  margin-bottom: 0.65rem;
}

.pie-collocation-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.pie-tag {
  display: inline-block;
  padding: 0.35rem 0.75rem;
  background: rgba(245, 158, 11, 0.12);
  border: 1px solid rgba(245, 158, 11, 0.3);
  border-radius: 8px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: #fde68a;
}

.pie-modal-sentence-text {
  font-size: 1.05rem;
  line-height: 1.6;
  color: #f1f5f9;
  margin: 0;
}

.btn-copy-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.3rem 0.65rem;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-fluid);
}

.btn-copy-tag:hover {
  background: rgba(56, 189, 248, 0.15);
  border-color: var(--neon-cyan);
  color: #fff;
}

.btn-copy-tag.copied {
  background: rgba(16, 185, 129, 0.2);
  border-color: var(--color-to);
  color: #34d399;
}

.pie-modal-actions {
  display: flex;
  margin-top: 0.5rem;
}

.btn-pie-exam-link {
  width: 100%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.65rem;
  padding: 0.85rem 1.25rem;
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.25), rgba(217, 119, 6, 0.35));
  border: 1px solid var(--neon-amber);
  border-radius: 12px;
  color: #fff;
  font-family: var(--font-display);
  font-size: 0.92rem;
  font-weight: 700;
  text-decoration: none;
  box-shadow: 0 4px 20px rgba(245, 158, 11, 0.2);
  transition: var(--transition-fluid);
  cursor: pointer;
}

.btn-pie-exam-link:hover {
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.4), rgba(217, 119, 6, 0.55));
  box-shadow: 0 6px 26px rgba(245, 158, 11, 0.35);
  transform: translateY(-1px);
}

/* Responsive Overrides */
@media (max-width: 900px) {
  .cinematic-nav {
    padding: 0.75rem 1rem;
  }
  .btn-theater-action span {
    display: none;
  }
  .cinematic-main {
    padding: 1rem 1rem 6.5rem;
  }
  .radar-sentence-output-grid {
    grid-template-columns: 1fr;
  }
  .anatomy-structures-grid {
    grid-template-columns: 1fr;
  }
  .prep-explanation-grid {
    grid-template-columns: 1fr;
  }
  .static-pie-split-layout {
    grid-template-columns: 1fr;
  }
}