@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=Figtree:wght@400;500;600;700;800&family=IBM+Plex+Sans+Arabic:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500;600;700&display=swap');

:root {
  /* =================================================================
     UI/UX Pro Max — Spatial Glass + Bento Clinical Design Tokens (Light)
     ================================================================= */
  --color-primary: #0284C7;
  --color-primary-hover: #0369A1;
  --color-primary-soft: rgba(2, 132, 199, 0.10);
  --color-primary-glow: rgba(2, 132, 199, 0.28);
  --color-secondary: #06B6D4;
  --color-accent: #059669;
  --color-accent-hover: #047857;
  --color-accent-soft: rgba(5, 150, 105, 0.11);

  --color-bg: #EEF4F9;
  --color-header-bg: rgba(255, 255, 255, 0.94);
  --color-bg-elevated: rgba(255, 255, 255, 0.85);
  --color-card: rgba(255, 255, 255, 0.78);
  --color-card-solid: #FFFFFF;
  --color-card-alt: rgba(241, 245, 249, 0.78);
  --color-foreground: #0F172A;
  --color-heading: #091E3A;
  --color-muted: #E2E8F0;
  --color-muted-fg: #475569;
  --color-border: rgba(148, 163, 184, 0.30);
  --color-border-strong: rgba(14, 165, 233, 0.35);
  --color-border-accent: rgba(6, 182, 212, 0.42);

  --glass-specular: rgba(255, 255, 255, 0.85);
  --glass-blur: 28px;
  --spotlight-color: rgba(14, 165, 233, 0.09);

  --color-success: #059669;
  --color-success-bg: rgba(16, 185, 129, 0.11);
  --color-success-border: rgba(16, 185, 129, 0.38);

  --color-warning: #D97706;
  --color-warning-bg: rgba(245, 158, 11, 0.12);
  --color-warning-border: rgba(245, 158, 11, 0.40);

  --color-danger: #DC2626;
  --color-danger-bg: rgba(239, 68, 68, 0.11);
  --color-danger-border: rgba(239, 68, 68, 0.38);

  --shadow-sm: 0 2px 8px -2px rgba(15, 23, 42, 0.06), inset 0 1px 0 0 var(--glass-specular);
  --shadow-md: 0 12px 32px -8px rgba(15, 23, 42, 0.08), 0 4px 12px -2px rgba(2, 132, 199, 0.05), inset 0 1px 0 0 var(--glass-specular);
  --shadow-lg: 0 22px 48px -12px rgba(15, 23, 42, 0.14), 0 8px 20px -4px rgba(2, 132, 199, 0.08), inset 0 1px 0 0 var(--glass-specular);
  --shadow-xl: 0 32px 64px -12px rgba(15, 23, 42, 0.24), inset 0 1px 0 0 var(--glass-specular);

  --radius-xs: 8px;
  --radius-sm: 12px;
  --radius-md: 16px;
  --radius-lg: 22px;
  --radius-xl: 28px;

  --font-sans: 'Plus Jakarta Sans', 'IBM Plex Sans Arabic', 'Figtree', -apple-system, sans-serif;
  --font-en: 'Plus Jakarta Sans', 'Figtree', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --orb-1: rgba(14, 165, 233, 0.22);
  --orb-2: rgba(16, 185, 129, 0.18);
  --orb-3: rgba(99, 102, 241, 0.14);
  --grid-line: rgba(15, 23, 42, 0.045);
}

[data-theme="dark"] {
  /* =================================================================
     UI/UX Pro Max — Spatial Obsidian & Bioluminescent Glass (Dark)
     ================================================================= */
  --color-primary: #38BDF8;
  --color-primary-hover: #0EA5E9;
  --color-primary-soft: rgba(56, 189, 248, 0.13);
  --color-primary-glow: rgba(56, 189, 248, 0.32);
  --color-secondary: #22D3EE;
  --color-accent: #10B981;
  --color-accent-hover: #059669;
  --color-accent-soft: rgba(16, 185, 129, 0.14);

  --color-bg: #050914;
  --color-header-bg: rgba(7, 12, 24, 0.94);
  --color-bg-elevated: rgba(15, 23, 42, 0.82);
  --color-card: rgba(13, 21, 38, 0.72);
  --color-card-solid: #0D1526;
  --color-card-alt: rgba(20, 31, 54, 0.68);
  --color-foreground: #F1F5F9;
  --color-heading: #FFFFFF;
  --color-muted: #1E293B;
  --color-muted-fg: #94A3B8;
  --color-border: rgba(148, 163, 184, 0.15);
  --color-border-strong: rgba(56, 189, 248, 0.35);
  --color-border-accent: rgba(34, 211, 238, 0.32);

  --glass-specular: rgba(255, 255, 255, 0.11);
  --glass-blur: 32px;
  --spotlight-color: rgba(56, 189, 248, 0.11);

  --color-success: #34D399;
  --color-success-bg: rgba(6, 78, 59, 0.38);
  --color-success-border: rgba(16, 185, 129, 0.42);

  --color-warning: #FBBF24;
  --color-warning-bg: rgba(120, 53, 15, 0.36);
  --color-warning-border: rgba(245, 158, 11, 0.45);

  --color-danger: #F87171;
  --color-danger-bg: rgba(127, 29, 29, 0.38);
  --color-danger-border: rgba(239, 68, 68, 0.45);

  --shadow-sm: 0 4px 14px -2px rgba(0, 0, 0, 0.45), inset 0 1px 0 0 var(--glass-specular);
  --shadow-md: 0 18px 42px -10px rgba(0, 0, 0, 0.55), 0 4px 16px -2px rgba(14, 165, 233, 0.08), inset 0 1px 0 0 var(--glass-specular);
  --shadow-lg: 0 28px 60px -12px rgba(0, 0, 0, 0.70), 0 0 28px -4px rgba(56, 189, 248, 0.14), inset 0 1px 0 0 var(--glass-specular);
  --shadow-xl: 0 36px 80px -12px rgba(0, 0, 0, 0.85), inset 0 1px 0 0 rgba(255, 255, 255, 0.18);

  --orb-1: rgba(14, 165, 233, 0.18);
  --orb-2: rgba(16, 185, 129, 0.14);
  --orb-3: rgba(59, 130, 246, 0.14);
  --grid-line: rgba(255, 255, 255, 0.032);
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-foreground);
  line-height: 1.65;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow-x: clip;
  transition: background-color 300ms ease, color 300ms ease;
}

/* Custom Sleek Scrollbars */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: 999px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--color-primary);
}

/* Accessibility Focus */
:focus-visible {
  outline: 2.5px solid var(--color-primary);
  outline-offset: 3px;
}

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

/* =================================================================
   Spatial Ambient Mesh & Architectural Grid Background
   ================================================================= */
.spatial-ambient-canvas {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  overflow: hidden;
}

.ambient-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(95px);
  will-change: transform;
  animation: floatOrb 22s ease-in-out infinite alternate;
}

.orb-1 {
  width: 560px;
  height: 560px;
  background: radial-gradient(circle, var(--orb-1) 0%, transparent 70%);
  top: -160px;
  left: -120px;
}

.orb-2 {
  width: 520px;
  height: 520px;
  background: radial-gradient(circle, var(--orb-2) 0%, transparent 70%);
  bottom: -140px;
  right: -100px;
  animation-delay: -7s;
  animation-duration: 26s;
}

.orb-3 {
  width: 440px;
  height: 440px;
  background: radial-gradient(circle, var(--orb-3) 0%, transparent 70%);
  top: 28%;
  left: 42%;
  animation-delay: -13s;
  animation-duration: 30s;
}

@keyframes floatOrb {
  0% { transform: translate3d(0, 0, 0) scale(1); }
  50% { transform: translate3d(38px, -28px, 0) scale(1.06); }
  100% { transform: translate3d(-26px, 32px, 0) scale(0.96); }
}

.spatial-grid-overlay {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--grid-line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid-line) 1px, transparent 1px);
  background-size: 38px 38px;
  mask-image: radial-gradient(ellipse 85% 75% at 50% 25%, #000 35%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 85% 75% at 50% 25%, #000 35%, transparent 100%);
}

/* =================================================================
   Docked Spatial Glass Command Bar (Header — Zero Page Overlap)
   ================================================================= */
.app-header {
  position: sticky;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  width: 100%;
  margin: 0;
  padding: 0;
}

/* Frosted glass backdrop placed on ::before so .app-header never creates
   a containing block that traps position:fixed children (.nav-tabs on mobile) */
.app-header::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background: var(--color-header-bg);
  backdrop-filter: blur(28px) saturate(190%);
  -webkit-backdrop-filter: blur(28px) saturate(190%);
  border-bottom: 1px solid var(--color-border);
  box-shadow: 0 8px 28px -8px rgba(0, 0, 0, 0.28);
}

.header-inner {
  max-width: 1440px;
  width: 100%;
  margin: 0 auto;
  min-height: 70px;
  padding: 0.55rem 1.35rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.85rem;
  flex-wrap: nowrap;
}

.brand-group {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
  flex: 1 1 auto;
  overflow: hidden;
}

.brand-copy {
  min-width: 0;
  flex: 1 1 auto;
  overflow: hidden;
}

.brand-logo {
  position: relative;
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: linear-gradient(135deg, #0EA5E9 0%, #0284C7 48%, #10B981 100%);
  color: #FFFFFF;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 6px 16px -4px rgba(14, 165, 233, 0.45), inset 0 1px 1px rgba(255, 255, 255, 0.45);
  flex-shrink: 0;
  overflow: hidden;
}

.brand-logo-glow {
  position: absolute;
  inset: -40%;
  background: radial-gradient(circle, rgba(255,255,255,0.35) 0%, transparent 65%);
  animation: pulseGlow 4s ease-in-out infinite alternate;
}

@keyframes pulseGlow {
  0% { opacity: 0.3; transform: scale(0.85); }
  100% { opacity: 0.75; transform: scale(1.15); }
}

.brand-badge-row {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  margin-bottom: 0.05rem;
}

.spatial-micro-tag {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--color-primary);
}

.brand-title {
  font-size: 1.05rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--color-heading);
  line-height: 1.2;
  white-space: nowrap;
}

.brand-subtitle {
  display: none;
}

/* Spatial Segmented Dock Navigation */
.nav-tabs {
  display: flex;
  align-items: center;
  gap: 0.28rem;
  background: var(--color-card-alt);
  padding: 0.3rem;
  border-radius: 14px;
  border: 1px solid var(--color-border);
  box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.08);
  flex-wrap: nowrap;
  white-space: nowrap;
}

.nav-tab {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.46rem 0.85rem;
  border-radius: 10px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--color-muted-fg);
  font-family: var(--font-sans);
  font-size: 0.83rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 220ms cubic-bezier(0.22, 1, 0.36, 1);
  min-height: 38px;
  white-space: nowrap;
  flex-shrink: 0;
}

.nav-tab:hover {
  color: var(--color-heading);
  background: var(--color-primary-soft);
}

.nav-tab.active {
  background: linear-gradient(135deg, #0284C7 0%, #0EA5E9 55%, #059669 100%);
  color: #FFFFFF !important;
  border-color: rgba(255, 255, 255, 0.22);
  box-shadow: 0 6px 16px -3px rgba(14, 165, 233, 0.38), inset 0 1px 0 rgba(255, 255, 255, 0.35);
  transform: translateY(-1px);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  flex-shrink: 0;
}

.header-inner > .header-actions {
  width: auto !important;
  flex-shrink: 0;
  margin-inline-start: auto;
}

.theme-orb-btn {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  border: 1px solid var(--color-border);
  background: var(--color-card-alt);
  color: var(--color-heading);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  flex-shrink: 0;
  transition: all 240ms cubic-bezier(0.22, 1, 0.36, 1);
  box-shadow: var(--shadow-sm);
}

.theme-orb-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: rotate(14deg) scale(1.05);
  box-shadow: 0 0 18px var(--color-primary-glow);
}

.ai-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.45rem 0.9rem;
  border-radius: 999px;
  background: var(--color-success-bg);
  border: 1px solid var(--color-success-border);
  color: var(--color-success);
  font-size: 0.8rem;
  font-weight: 700;
  font-family: var(--font-mono);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-success);
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.25);
  animation: statusPulse 2s infinite;
}

@keyframes statusPulse {
  0%, 100% { box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.22); }
  50% { box-shadow: 0 0 0 6px rgba(16, 185, 129, 0.05); }
}

/* =================================================================
   Main Workspace & Bento Telemetry Strip
   ================================================================= */
.main-container {
  max-width: 1440px;
  width: 100%;
  margin: 0 auto;
  padding: 1.85rem 1.35rem 3.5rem;
  flex: 1;
}

.view-section {
  display: none;
}

.view-section.active {
  display: block;
}

/* Bento Telemetry Strip */
.bento-telemetry-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.1rem;
  margin-bottom: 1.25rem;
}

@media (max-width: 1024px) {
  .bento-telemetry-strip {
    grid-template-columns: 1fr;
  }
}

.bento-stat-tile {
  position: relative;
  display: flex;
  align-items: center;
  gap: 0.9rem;
  padding: 0.95rem 1.2rem;
  background: var(--color-card);
  backdrop-filter: blur(var(--glass-blur)) saturate(180%);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(180%);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 240ms cubic-bezier(0.22, 1, 0.36, 1), border-color 240ms ease, box-shadow 240ms ease;
}

.bento-stat-tile:hover {
  transform: translateY(-2px);
  border-color: var(--color-border-strong);
  box-shadow: var(--shadow-md);
}

.bento-stat-icon {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.bento-stat-icon.cyan {
  background: var(--color-primary-soft);
  color: var(--color-primary);
  border: 1px solid var(--color-border-accent);
}

.bento-stat-icon.emerald {
  background: var(--color-success-bg);
  color: var(--color-success);
  border: 1px solid var(--color-success-border);
}

.bento-stat-icon.violet {
  background: rgba(99, 102, 241, 0.14);
  color: #818CF8;
  border: 1px solid rgba(99, 102, 241, 0.32);
}

.bento-stat-content {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.bento-stat-label {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--color-muted-fg);
  text-transform: uppercase;
}

.bento-stat-value {
  font-size: 0.94rem;
  font-weight: 700;
  color: var(--color-heading);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.bento-live-pill {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 700;
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  border: 1px solid var(--color-border-accent);
  white-space: nowrap;
}

.bento-live-pill.emerald {
  background: var(--color-success-bg);
  color: var(--color-success);
  border-color: var(--color-success-border);
}

/* =================================================================
   Spatial OS Window Cards & Interactive Cursor Spotlight
   ================================================================= */
.studio-grid {
  display: grid;
  grid-template-columns: 1fr 1.32fr;
  gap: 1.35rem;
  align-items: start;
}

@media (max-width: 1040px) {
  .studio-grid {
    grid-template-columns: 1fr;
  }
}

.clinical-card,
.spatial-window {
  position: relative;
  background: var(--color-card);
  backdrop-filter: blur(var(--glass-blur)) saturate(185%);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(185%);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.55rem;
  box-shadow: var(--shadow-md);
  margin-bottom: 1.35rem;
  overflow: hidden;
  transition: border-color 260ms ease, box-shadow 260ms ease, transform 260ms cubic-bezier(0.22, 1, 0.36, 1);
}

.clinical-card:hover {
  border-color: var(--color-border-strong);
}

/* Interactive Cursor Spotlight Overlay */
.spotlight-card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: radial-gradient(
    520px circle at var(--mouse-x, -500px) var(--mouse-y, -500px),
    var(--spotlight-color),
    transparent 45%
  );
  pointer-events: none;
  z-index: 0;
  opacity: 0;
  transition: opacity 300ms ease;
}

.spotlight-card:hover::before {
  opacity: 1;
}

.clinical-card > *,
.question-box > *,
.bento-stat-tile > * {
  position: relative;
  z-index: 1;
}

/* Spatial Window Chrome Top Bar */
.window-chrome-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 0.75rem;
  margin-bottom: 0.95rem;
  border-bottom: 1px dashed var(--color-border);
}

.window-dots {
  display: flex;
  align-items: center;
  gap: 0.42rem;
}

.w-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  display: inline-block;
}

.dot-cyan {
  background: #38BDF8;
  box-shadow: 0 0 8px rgba(56, 189, 248, 0.65);
}

.dot-emerald {
  background: #34D399;
  box-shadow: 0 0 8px rgba(52, 211, 153, 0.65);
}

.dot-amber {
  background: #FBBF24;
  box-shadow: 0 0 8px rgba(251, 191, 36, 0.55);
}

.window-tag {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--color-muted-fg);
  text-transform: uppercase;
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.85rem;
  margin-bottom: 1.25rem;
  padding-bottom: 0.95rem;
  border-bottom: 1px solid var(--color-border);
  flex-wrap: wrap;
}

.card-title-group {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.card-icon {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--color-primary-soft), var(--color-accent-soft));
  border: 1px solid var(--color-border-accent);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  box-shadow: inset 0 1px 0 var(--glass-specular);
}

.card-title {
  font-size: 1.12rem;
  font-weight: 800;
  letter-spacing: -0.015em;
  color: var(--color-heading);
}

.card-subtitle {
  font-size: 0.83rem;
  color: var(--color-muted-fg);
}

/* =================================================================
   Holographic Upload Dropzone & Textbook Cards
   ================================================================= */
.upload-dropzone {
  position: relative;
  border: 1.5px dashed var(--color-border-strong);
  background: linear-gradient(145deg, var(--color-primary-soft), rgba(16, 185, 129, 0.04));
  border-radius: var(--radius-md);
  padding: 1.65rem 1.25rem;
  text-align: center;
  cursor: pointer;
  transition: all 240ms cubic-bezier(0.22, 1, 0.36, 1);
  margin-bottom: 1.35rem;
  overflow: hidden;
}

.upload-dropzone:hover,
.upload-dropzone.dragover {
  transform: translateY(-2px);
  border-color: var(--color-accent);
  box-shadow: 0 12px 30px -8px var(--color-primary-glow);
}

.upload-orbital-ring {
  width: 66px;
  height: 66px;
  margin: 0 auto 0.85rem;
  border-radius: 50%;
  padding: 6px;
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.25), rgba(16, 185, 129, 0.25));
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 24px var(--color-primary-glow);
}

.upload-icon-wrap {
  width: 54px;
  height: 54px;
  border-radius: 50%;
  background: var(--color-card-solid);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
  transition: transform 240ms ease;
}

.upload-dropzone:hover .upload-icon-wrap {
  transform: scale(1.08) translateY(-2px);
}

.upload-title {
  font-weight: 700;
  font-size: 0.96rem;
  color: var(--color-heading);
  margin-bottom: 0.3rem;
}

.upload-hint {
  font-size: 0.8rem;
  color: var(--color-muted-fg);
}

/* Live Animated Upload & Indexing Progress Bar Panel */
.upload-progress-panel {
  padding: 1.1rem 1.2rem;
  margin-bottom: 1.35rem;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--color-card-alt), var(--color-primary-soft));
  border: 1px solid var(--color-border-strong);
  box-shadow: var(--shadow-md);
  animation: fadeIn 240ms ease;
}

.upload-progress-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 0.65rem;
  flex-wrap: wrap;
}

.upload-progress-status-group {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  min-width: 0;
  flex: 1;
}

.upload-mini-spinner {
  width: 17px;
  height: 17px;
  border-width: 2.2px;
  border-color: var(--color-border);
  border-top-color: var(--color-primary);
  flex-shrink: 0;
}

.upload-stage-label {
  font-size: 0.88rem;
  font-weight: 800;
  color: var(--color-heading);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.upload-progress-track {
  position: relative;
  width: 100%;
  height: 14px;
  border-radius: 999px;
  background: var(--color-card-solid);
  border: 1px solid var(--color-border);
  overflow: hidden;
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.18);
}

.upload-progress-bar-fill {
  position: relative;
  height: 100%;
  width: 0%;
  border-radius: 999px;
  background-color: #0EA5E9;
  background-image:
    linear-gradient(
      45deg,
      rgba(255, 255, 255, 0.24) 25%,
      transparent 25%,
      transparent 50%,
      rgba(255, 255, 255, 0.24) 50%,
      rgba(255, 255, 255, 0.24) 75%,
      transparent 75%,
      transparent
    ),
    linear-gradient(90deg, #0284C7 0%, #0EA5E9 50%, #10B981 100%);
  background-size: 26px 26px, 100% 100%;
  animation: progressStripesMove 0.75s linear infinite;
  box-shadow: 0 0 16px rgba(14, 165, 233, 0.65);
  transition: width 220ms cubic-bezier(0.22, 1, 0.36, 1);
}

.upload-progress-bar-fill.completed {
  background-image: linear-gradient(90deg, #059669 0%, #10B981 55%, #34D399 100%);
  box-shadow: 0 0 18px rgba(16, 185, 129, 0.75);
  animation: none;
}

@keyframes progressStripesMove {
  0% { background-position: 0 0, 0 0; }
  100% { background-position: 26px 0, 0 0; }
}

.upload-progress-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-top: 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-muted-fg);
  flex-wrap: wrap;
}

.section-subbar {
  margin-bottom: 0.65rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* Book Shelf List */
.book-list {
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}

.book-item {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.85rem;
  padding: 0.95rem 1.1rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-card-alt);
  cursor: pointer;
  transition: all 220ms cubic-bezier(0.22, 1, 0.36, 1);
  overflow: hidden;
}

.book-item::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  inset-inline-start: 0;
  width: 4px;
  background: transparent;
  transition: background 220ms ease;
}

.book-item:hover {
  border-color: var(--color-border-strong);
  transform: translateX(3px);
}

[dir="rtl"] .book-item:hover {
  transform: translateX(-3px);
}

.book-item.selected {
  border-color: var(--color-primary);
  background: linear-gradient(135deg, var(--color-primary-soft), rgba(16, 185, 129, 0.06));
  box-shadow: 0 8px 24px -6px var(--color-primary-glow);
}

.book-item.selected::after {
  background: linear-gradient(to bottom, var(--color-primary), var(--color-accent));
}

.book-info {
  flex: 1;
  min-width: 0;
}

.book-name {
  font-weight: 800;
  font-size: 0.96rem;
  color: var(--color-heading);
  margin-bottom: 0.28rem;
  word-break: break-word;
}

.book-meta {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  font-size: 0.79rem;
  color: var(--color-muted-fg);
  flex-wrap: wrap;
}

/* Guarantee Bento Card */
.guarantee-bento-card {
  background: linear-gradient(135deg, var(--color-card), var(--color-primary-soft));
  border-color: var(--color-border-accent);
}

.guarantee-inner {
  display: flex;
  gap: 0.95rem;
  align-items: flex-start;
}

.guarantee-shield-icon {
  background: var(--color-success-bg);
  color: var(--color-success);
  border-color: var(--color-success-border);
}

.guarantee-title {
  font-size: 0.96rem;
  font-weight: 800;
  color: var(--color-heading);
  margin-bottom: 0.3rem;
}

.guarantee-desc {
  font-size: 0.84rem;
  color: var(--color-muted-fg);
  line-height: 1.65;
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.32rem;
  padding: 0.24rem 0.68rem;
  border-radius: 999px;
  font-size: 0.74rem;
  font-weight: 700;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  border: 1px solid var(--color-border-accent);
}

.badge-mono {
  font-family: var(--font-mono);
}

.badge-glow {
  box-shadow: 0 0 12px var(--color-primary-glow);
}

.badge-success {
  background: var(--color-success-bg);
  color: var(--color-success);
  border: 1px solid var(--color-success-border);
}

.badge-warning {
  background: var(--color-warning-bg);
  color: var(--color-warning);
  border: 1px solid var(--color-warning-border);
}

/* =================================================================
   Segmented Mode Switcher & Chapters Matrix
   ================================================================= */
.mode-switcher {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.5rem;
  background: var(--color-card-alt);
  padding: 0.38rem;
  border-radius: 14px;
  border: 1px solid var(--color-border);
  margin-bottom: 1.2rem;
}

.mode-btn {
  padding: 0.68rem 1rem;
  border: 1px solid transparent;
  border-radius: 10px;
  background: transparent;
  color: var(--color-muted-fg);
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 0.88rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: all 200ms cubic-bezier(0.22, 1, 0.36, 1);
}

.mode-btn:hover {
  color: var(--color-heading);
}

.mode-btn.active {
  background: var(--color-card-solid);
  color: var(--color-primary);
  border-color: var(--color-border-accent);
  box-shadow: var(--shadow-sm);
}

.scope-glass-panel {
  margin-bottom: 1.25rem;
}

.chapters-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.55rem;
  margin-bottom: 0.7rem;
}

.search-input-wrapper {
  position: relative;
  flex: 1;
  display: flex;
  align-items: center;
}

.search-icon-inline {
  position: absolute;
  inset-inline-start: 0.85rem;
  color: var(--color-muted-fg);
  pointer-events: none;
}

.chapters-search {
  width: 100%;
  padding: 0.6rem 0.9rem;
  padding-inline-start: 2.35rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-card-alt);
  color: var(--color-foreground);
  font-family: var(--font-sans);
  font-size: 0.87rem;
  transition: all 180ms ease;
}

.chapters-search:focus {
  border-color: var(--color-primary);
  outline: none;
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}

.chapters-container {
  max-height: 295px;
  overflow-y: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 0.55rem;
  background: var(--color-card-alt);
  display: flex;
  flex-direction: column;
  gap: 0.42rem;
}

.chapter-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.68rem 0.9rem;
  border-radius: 11px;
  background: var(--color-card-solid);
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: all 180ms cubic-bezier(0.22, 1, 0.36, 1);
}

.chapter-row:hover {
  border-color: var(--color-primary);
  transform: translateX(3px);
}

[dir="rtl"] .chapter-row:hover {
  transform: translateX(-3px);
}

.chapter-row.checked {
  border-color: var(--color-primary);
  background: linear-gradient(90deg, var(--color-primary-soft), transparent);
  box-shadow: inset 3px 0 0 var(--color-primary);
}

.chapter-row input[type="checkbox"] {
  width: 18px;
  height: 18px;
  accent-color: var(--color-primary);
  cursor: pointer;
  flex-shrink: 0;
}

.chapter-label {
  flex: 1;
  font-size: 0.87rem;
  font-weight: 600;
  color: var(--color-foreground);
  direction: ltr;
  text-align: left;
}

.chapter-pages-pill {
  font-family: var(--font-mono);
  font-size: 0.73rem;
  font-weight: 600;
  padding: 0.22rem 0.58rem;
  border-radius: 7px;
  background: var(--color-card-alt);
  border: 1px solid var(--color-border);
  color: var(--color-primary);
  white-space: nowrap;
}

/* Page Range Selector & HUD Preview */
.page-range-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  padding: 1.05rem;
  background: var(--color-card-alt);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
}

.range-number-input {
  font-family: var(--font-mono) !important;
  font-size: 1.08rem !important;
  font-weight: 700 !important;
  color: var(--color-primary) !important;
}

.hud-scope-preview {
  margin-top: 0.85rem;
  padding: 0.9rem 1.1rem;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--color-primary-soft), var(--color-accent-soft));
  border: 1px solid var(--color-border-accent);
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--color-heading);
  box-shadow: inset 0 1px 0 var(--glass-specular);
}

.range-helper-meta {
  font-size: 0.79rem;
  color: var(--color-muted-fg);
  margin-top: 0.45rem;
  font-family: var(--font-mono);
}

/* =================================================================
   Form Controls & Liquid Shimmer Buttons
   ================================================================= */
.form-group {
  margin-bottom: 1.1rem;
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--color-heading);
  margin-bottom: 0.42rem;
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 0.72rem 0.95rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-card-solid);
  color: var(--color-foreground);
  font-family: var(--font-sans);
  font-size: 0.92rem;
  font-weight: 500;
  transition: border-color 180ms ease, box-shadow 180ms ease, transform 180ms ease;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  border-color: var(--color-primary);
  outline: none;
  box-shadow: 0 0 0 3.5px var(--color-primary-soft);
}

.options-grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

@media (max-width: 640px) {
  .options-grid-2,
  .page-range-grid {
    grid-template-columns: 1fr;
  }
}

.btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  padding: 0.78rem 1.4rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 0.93rem;
  font-weight: 700;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 220ms cubic-bezier(0.22, 1, 0.36, 1);
  min-height: 44px;
  overflow: hidden;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.btn-primary {
  background: linear-gradient(135deg, #0284C7 0%, #0EA5E9 48%, #059669 100%);
  color: #FFFFFF;
  border-color: rgba(255, 255, 255, 0.22);
  box-shadow: 0 10px 24px -6px rgba(14, 165, 233, 0.45), inset 0 1px 0 rgba(255, 255, 255, 0.35);
}

.btn-primary:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 14px 30px -6px rgba(14, 165, 233, 0.60), inset 0 1px 0 rgba(255, 255, 255, 0.45);
}

.btn-primary:active:not(:disabled) {
  transform: translateY(0);
}

/* Liquid Specular Shimmer Sweep */
.btn-shimmer::after {
  content: "";
  position: absolute;
  top: -50%;
  left: -60%;
  width: 40%;
  height: 200%;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.28),
    transparent
  );
  transform: rotate(25deg);
  animation: liquidSweep 4.5s ease-in-out infinite;
  pointer-events: none;
}

@keyframes liquidSweep {
  0%, 55% { left: -60%; }
  100% { left: 140%; }
}

.btn-secondary {
  background: var(--color-card-alt);
  color: var(--color-foreground);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover:not(:disabled) {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: translateY(-1px);
}

.btn-sm {
  padding: 0.44rem 0.88rem;
  font-size: 0.81rem;
  min-height: 36px;
  border-radius: 10px;
}

.btn-xs {
  padding: 0.34rem 0.72rem;
  font-size: 0.75rem;
  min-height: 30px;
  border-radius: 8px;
}

.btn-block {
  width: 100%;
}

/* =================================================================
   Active Exam HUD & Clinical Question Terminal
   ================================================================= */
.exam-top-bar {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.2rem 1.45rem 1.05rem;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
}

.exam-progress-rail {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--color-border);
  overflow: hidden;
}

.exam-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #0EA5E9, #10B981);
  box-shadow: 0 0 12px #0EA5E9;
  transition: width 380ms cubic-bezier(0.22, 1, 0.36, 1);
}

.exam-scope-caption {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--color-primary);
  font-weight: 600;
}

.exam-question-counter {
  font-weight: 800;
  font-size: 1.08rem;
  color: var(--color-heading);
}

.exam-hud-right {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.question-pills-nav {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  flex-wrap: wrap;
}

.q-pill {
  width: 40px;
  height: 40px;
  border-radius: 11px;
  border: 1px solid var(--color-border);
  background: var(--color-card-alt);
  color: var(--color-foreground);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.88rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 200ms cubic-bezier(0.22, 1, 0.36, 1);
}

.q-pill:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
}

.q-pill.current {
  border-color: rgba(255, 255, 255, 0.3);
  background: linear-gradient(135deg, #0284C7, #059669);
  color: #FFFFFF !important;
  box-shadow: 0 6px 14px -3px var(--color-primary-glow);
  transform: scale(1.06);
}

.q-pill.graded-correct {
  background: var(--color-success-bg);
  border-color: var(--color-success-border);
  color: var(--color-success);
}

.q-pill.graded-partial {
  background: var(--color-warning-bg);
  border-color: var(--color-warning-border);
  color: var(--color-warning);
}

.q-pill.graded-incorrect {
  background: var(--color-danger-bg);
  border-color: var(--color-danger-border);
  color: var(--color-danger);
}

/* Question Terminal Box */
.question-box {
  padding: 1.85rem;
  margin-bottom: 1.5rem;
}

.question-meta-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
}

.question-en-text {
  font-family: var(--font-en);
  direction: ltr;
  text-align: left;
  font-size: 1.14rem;
  font-weight: 600;
  line-height: 1.72;
  color: var(--color-heading);
  background: var(--color-card-alt);
  padding: 1.35rem 1.5rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  margin-bottom: 1.05rem;
  box-shadow: inset 0 1px 0 var(--glass-specular);
}

.question-ar-text {
  direction: rtl;
  text-align: right;
  font-size: 1.05rem;
  font-weight: 500;
  line-height: 1.8;
  color: var(--color-foreground);
  background: var(--color-primary-soft);
  padding: 1.2rem 1.4rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-accent);
  border-right: 4px solid var(--color-accent);
  margin-bottom: 1.2rem;
}

.clinical-hint-banner {
  padding: 0.95rem 1.2rem;
  border-radius: var(--radius-sm);
  background: var(--color-warning-bg);
  border: 1px solid var(--color-warning-border);
  color: var(--color-warning);
  margin-bottom: 1.2rem;
  font-size: 0.92rem;
}

.answer-studio-Header,
.answer-studio-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.55rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.kbd-hint-pill {
  font-size: 0.77rem;
  color: var(--color-muted-fg);
}

.kbd-hint-pill kbd {
  font-family: var(--font-mono);
  font-size: 0.73rem;
  padding: 2px 7px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: var(--color-card-alt);
  color: var(--color-primary);
}

.answer-textarea {
  width: 100%;
  min-height: 160px;
  padding: 1.1rem 1.25rem;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-card-solid);
  color: var(--color-foreground);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.7;
  resize: vertical;
  transition: border-color 200ms ease, box-shadow 200ms ease;
}

.answer-textarea:focus {
  border-color: var(--color-primary);
  outline: none;
  box-shadow: 0 0 0 4px var(--color-primary-soft), 0 8px 24px -6px var(--color-primary-glow);
}

.exam-action-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-top: 1.15rem;
  flex-wrap: wrap;
}

/* =================================================================
   Grading Feedback Bento Report & Animated SVG Score Gauge
   ================================================================= */
.feedback-card {
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  margin-top: 1.65rem;
  border: 1.5px solid var(--color-border);
  background: var(--color-card-solid);
  box-shadow: var(--shadow-lg);
}

.feedback-card.verdict-correct {
  border-color: var(--color-success-border);
  background: linear-gradient(180deg, var(--color-success-bg) 0%, var(--color-card-solid) 165px);
}

.feedback-card.verdict-partial {
  border-color: var(--color-warning-border);
  background: linear-gradient(180deg, var(--color-warning-bg) 0%, var(--color-card-solid) 165px);
}

.feedback-card.verdict-incorrect {
  border-color: var(--color-danger-border);
  background: linear-gradient(180deg, var(--color-danger-bg) 0%, var(--color-card-solid) 165px);
}

.feedback-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.15rem;
  margin-bottom: 1.35rem;
  padding-bottom: 1.1rem;
  border-bottom: 1px solid var(--color-border);
  flex-wrap: wrap;
}

/* Animated SVG Score Gauge Ring */
.score-gauge-wrap {
  position: relative;
  width: 82px;
  height: 82px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.score-gauge-svg {
  width: 82px;
  height: 82px;
  transform: rotate(-90deg);
}

.score-gauge-bg {
  fill: none;
  stroke: var(--color-border);
  stroke-width: 7;
}

.score-gauge-fill {
  fill: none;
  stroke-width: 7;
  stroke-linecap: round;
  transition: stroke-dashoffset 950ms cubic-bezier(0.22, 1, 0.36, 1);
}

.score-gauge-label {
  position: absolute;
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 1.12rem;
}

.feedback-grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.05rem;
  margin: 1.2rem 0;
}

@media (max-width: 768px) {
  .feedback-grid-2 {
    grid-template-columns: 1fr;
  }
}

.points-box {
  position: relative;
  padding: 1.15rem 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-card-alt);
  overflow: hidden;
}

.points-box h4 {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.93rem;
  font-weight: 800;
  margin-bottom: 0.7rem;
}

.points-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.48rem;
  font-size: 0.9rem;
}

.points-list li {
  position: relative;
  padding-inline-start: 1.2rem;
}

.points-list li::before {
  content: "▹";
  position: absolute;
  inset-inline-start: 0;
  font-weight: bold;
  color: var(--color-primary);
}

.canonical-answer-box {
  padding: 1.35rem;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--color-primary-soft), var(--color-accent-soft));
  border: 1px solid var(--color-border-accent);
  margin-top: 1.05rem;
}

.verbatim-quote-box {
  direction: ltr;
  text-align: left;
  font-family: var(--font-en);
  font-size: 0.92rem;
  padding: 1.1rem 1.3rem;
  border-radius: var(--radius-md);
  background: var(--color-card-alt);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-accent);
  color: var(--color-muted-fg);
  margin-top: 1.05rem;
  font-style: italic;
}

/* =================================================================
   Source Textbook Page Viewer & Spatial Modal Window
   ================================================================= */
.inspector-controls-bar {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.page-paper {
  direction: ltr;
  text-align: left;
  font-family: var(--font-en);
  background: var(--color-card-solid);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.6rem;
  margin-bottom: 1.1rem;
  box-shadow: var(--shadow-sm);
  white-space: pre-wrap;
  line-height: 1.75;
  font-size: 0.95rem;
}

.page-paper-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 0.75rem;
  margin-bottom: 0.95rem;
  border-bottom: 1px solid var(--color-border);
  font-weight: 800;
  color: var(--color-primary);
  flex-wrap: wrap;
  gap: 0.5rem;
}

/* Spatial Modal Backdrop & Window */
.modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 100;
  background: rgba(5, 9, 20, 0.72);
  backdrop-filter: blur(14px) saturate(160%);
  -webkit-backdrop-filter: blur(14px) saturate(160%);
  display: none;
  align-items: center;
  justify-content: center;
  padding: 1.25rem;
  perspective: 1100px;
}

.modal-backdrop.open {
  display: flex;
}

.modal-window {
  background: var(--color-card-solid);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-xl);
  max-width: 860px;
  width: 100%;
  max-height: 88vh;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-xl);
  padding: 1.35rem 1.55rem;
  margin-bottom: 0;
}

.modal-header {
  padding-bottom: 0.95rem;
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.modal-body {
  padding-top: 1.25rem;
  overflow-y: auto;
}

/* =================================================================
   Spatial Glass Toast Notifications & Spinner
   ================================================================= */
.toast-container {
  position: fixed;
  bottom: 1.5rem;
  left: 1.5rem;
  z-index: 120;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.toast {
  padding: 0.9rem 1.3rem;
  border-radius: 14px;
  background: var(--color-bg-elevated);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--color-border-strong);
  color: var(--color-heading);
  font-weight: 700;
  font-size: 0.88rem;
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.spinner {
  width: 20px;
  height: 20px;
  border: 2.5px solid rgba(255, 255, 255, 0.3);
  border-top-color: #FFFFFF;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* =================================================================
   UI/UX Pro Max — Universal Responsive Engine
   Supports All Devices: Desktop, iPad/Tablet (Landscape & Portrait),
   Phablets, Standard Mobile Phones, and Compact Phones (320px+)
   ================================================================= */

/* Default Desktop Navigation Labels */
.nav-label-short {
  display: none;
}

.nav-label-full {
  display: inline;
}

.exam-prev-next-group {
  display: flex;
  gap: 0.6rem;
}

.inspector-range-pair {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  flex-wrap: wrap;
}

.inspector-num-input {
  width: 92px;
  padding: 0.45rem 0.65rem;
}

.settings-lang-select-wrap {
  min-width: 260px;
}

.feedback-score-summary-group {
  display: flex;
  align-items: center;
  gap: 1.15rem;
  flex: 1;
  min-width: 0;
}

.feedback-verdict-copy {
  flex: 1;
  min-width: 0;
}

/* -----------------------------------------------------------------
   TIER 1: Landscape Tablets & Compact Laptops (861px – 1280px)
   (e.g. 13" Laptops, iPad Pro 11"/12.9", iPad Air, Galaxy Tab, Surface)
   ----------------------------------------------------------------- */
@media (max-width: 1280px) {
  .nav-label-full {
    display: none;
  }

  .nav-label-short {
    display: inline;
  }

  .nav-tab {
    padding: 0.46rem 0.78rem;
    font-size: 0.82rem;
  }
}

@media (max-width: 1180px) {
  .bento-telemetry-strip {
    grid-template-columns: repeat(2, 1fr);
  }

  .bento-telemetry-strip > .bento-stat-tile:nth-child(3) {
    grid-column: 1 / -1;
  }
}

/* -----------------------------------------------------------------
   TIER 2: Portrait Tablets & All Mobile Phones (<= 860px)
   Transforms Top Nav into an iOS / VisionOS Floating Bottom Dock!
   ----------------------------------------------------------------- */
@media (max-width: 860px) {
  .app-header {
    top: 0;
    margin: 0;
    padding: env(safe-area-inset-top, 0px) 0 0;
  }

  .header-inner {
    min-height: 60px;
    padding: 0.45rem 0.9rem;
    display: flex;
    flex-direction: row !important;
    align-items: center !important;
    justify-content: space-between !important;
    flex-wrap: nowrap !important;
    gap: 0.65rem;
  }

  .brand-group {
    min-width: 0;
    flex: 1 1 auto;
    gap: 0.65rem;
    overflow: hidden;
  }

  .brand-copy {
    min-width: 0;
    flex: 1 1 auto;
    overflow: hidden;
  }

  .brand-logo {
    width: 38px;
    height: 38px;
    border-radius: 11px;
  }

  .brand-title {
    font-size: clamp(0.92rem, 3.2vw, 1.05rem);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .brand-subtitle {
    display: none;
  }

  .header-inner > .header-actions {
    width: auto !important;
    flex: 0 0 auto !important;
    margin-inline-start: auto;
  }

  .theme-orb-btn {
    width: 38px;
    height: 38px;
    border-radius: 11px;
  }

  /* Floating Spatial Glass Bottom Navigation Dock */
  .nav-tabs {
    position: fixed;
    bottom: calc(0.55rem + env(safe-area-inset-bottom, 0px));
    left: 0.65rem;
    right: 0.65rem;
    z-index: 90;
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0.25rem;
    padding: 0.35rem;
    background: var(--color-bg-elevated);
    backdrop-filter: blur(32px) saturate(200%);
    -webkit-backdrop-filter: blur(32px) saturate(200%);
    border: 1px solid var(--color-border-strong);
    border-radius: 20px;
    box-shadow: 0 18px 42px -6px rgba(0, 0, 0, 0.55), inset 0 1px 0 var(--glass-specular);
  }

  .nav-tab {
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 0.22rem;
    padding: 0.42rem 0.2rem;
    min-height: 54px;
    border-radius: 14px;
    font-size: 0.68rem;
    font-weight: 700;
    line-height: 1.15;
    text-align: center;
  }

  .nav-tab svg {
    width: 19px;
    height: 19px;
    flex-shrink: 0;
  }

  .nav-label-full {
    display: none;
  }

  .nav-label-short {
    display: block;
    width: 100%;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  #active-exam-badge {
    position: absolute;
    top: 3px;
    inset-inline-end: 4px;
    padding: 0.08rem 0.36rem;
    font-size: 0.58rem;
  }

  /* Reserve space at bottom of workspace so Floating Bottom Dock never covers content */
  .main-container {
    padding: 1.35rem 0.85rem calc(6.5rem + env(safe-area-inset-bottom, 0px));
  }

  .bento-telemetry-strip {
    grid-template-columns: 1fr;
    gap: 0.75rem;
    margin-bottom: 1rem;
  }

  .bento-stat-tile {
    padding: 0.85rem 1rem;
  }

  .clinical-card,
  .spatial-window,
  .question-box {
    padding: 1.15rem;
    border-radius: 18px;
    margin-bottom: 1rem;
  }

  /* Keep toast above the Floating Bottom Dock */
  .toast-container {
    bottom: calc(5.4rem + env(safe-area-inset-bottom, 0px));
    left: 0.75rem;
    right: 0.75rem;
  }

  .toast {
    width: 100%;
    justify-content: center;
  }
}

/* -----------------------------------------------------------------
   TIER 3: Standard & Compact Mobile Phones (<= 640px)
   Touch-optimized controls (min 46px height, 16px font to prevent
   iOS Safari auto-zoom), wrapped toolbars, and Bottom-Sheet Modals
   ----------------------------------------------------------------- */
@media (max-width: 640px) {
  .brand-subtitle {
    display: none;
  }

  /* Prevent iOS Safari zoom on input focus & guarantee 46px+ touch targets */
  .form-input,
  .form-select,
  .form-textarea,
  .chapters-search,
  .answer-textarea {
    font-size: 16px !important;
    min-height: 46px;
  }

  .btn {
    min-height: 46px;
    font-size: 0.9rem;
    padding: 0.7rem 1rem;
  }

  .btn-sm {
    min-height: 40px;
    padding: 0.48rem 0.8rem;
  }

  .card-header {
    flex-direction: column;
    align-items: stretch;
    gap: 0.75rem;
  }

  .card-header > .btn,
  .card-header > .header-actions {
    width: 100%;
    justify-content: space-between;
  }

  .ai-status-pill {
    flex: 1;
    justify-content: center;
    font-size: 0.73rem;
    padding: 0.42rem 0.65rem;
  }

  .settings-lang-select-wrap {
    min-width: 0;
    width: 100%;
  }

  /* Mode Switcher (By Chapters vs By Page Range) */
  .mode-switcher {
    grid-template-columns: 1fr;
    gap: 0.4rem;
  }

  .mode-btn {
    min-height: 44px;
    justify-content: flex-start;
    padding: 0.65rem 0.95rem;
  }

  /* Chapters Search & Select/Clear Toolbar */
  .chapters-toolbar {
    flex-wrap: wrap;
    gap: 0.5rem;
  }

  .search-input-wrapper {
    flex: 1 1 100%;
    width: 100%;
  }

  .chapters-toolbar > .btn {
    flex: 1 1 calc(50% - 0.3rem);
  }

  /* Chapter Row Mobile Layout (No squished titles!) */
  .chapter-row {
    flex-wrap: wrap;
    padding: 0.75rem;
    gap: 0.45rem 0.65rem;
  }

  .chapter-label {
    flex: 1 1 calc(100% - 34px);
    font-size: 0.88rem;
    line-height: 1.4;
  }

  .chapter-pages-pill {
    margin-inline-start: 1.65rem;
    font-size: 0.72rem;
    white-space: normal;
  }

  /* Book Item Mobile Layout */
  .book-item {
    flex-wrap: wrap;
    padding: 0.85rem 0.95rem;
  }

  /* Active Exam Top HUD & Question Pills */
  .exam-top-bar {
    padding: 1rem;
    gap: 0.75rem;
  }

  .exam-hud-left,
  .exam-hud-right {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.45rem;
  }

  .question-pills-nav {
    width: 100%;
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-bottom: 0.25rem;
    -webkit-overflow-scrolling: touch;
  }

  .q-pill {
    width: 42px;
    height: 42px;
    flex-shrink: 0;
  }

  /* Question Meta Bar & Action Bar */
  .question-meta-bar {
    flex-direction: column;
    align-items: stretch;
    gap: 0.65rem;
  }

  .question-meta-bar > div {
    width: 100%;
  }

  .question-meta-bar > div:last-child > .btn {
    flex: 1;
  }

  .question-en-text,
  .question-ar-text {
    font-size: 1rem;
    padding: 1.05rem 1.15rem;
  }

  .exam-action-bar {
    flex-direction: column;
    align-items: stretch;
    gap: 0.65rem;
  }

  #btn-analyze-answer {
    order: -1;
    width: 100%;
    min-height: 50px;
  }

  .exam-prev-next-group {
    width: 100%;
  }

  .exam-prev-next-group > .btn {
    flex: 1;
  }

  /* Grading Feedback Mobile Layout */
  .feedback-card {
    padding: 1.2rem;
  }

  .feedback-header {
    flex-direction: column;
    align-items: stretch;
  }

  .feedback-score-summary-group {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.8rem;
  }

  .feedback-verify-btn {
    width: 100%;
  }

  /* Inspector Controls */
  .inspector-controls-bar {
    width: 100%;
    flex-direction: column;
    align-items: stretch;
  }

  .inspector-range-pair {
    width: 100%;
    justify-content: space-between;
  }

  .inspector-num-input {
    flex: 1;
    min-width: 70px;
  }

  .inspector-load-btn {
    width: 100%;
  }

  /* Native Bottom-Sheet Modal Drawer on Mobile */
  .modal-backdrop {
    align-items: flex-end;
    padding: 0;
  }

  .modal-window {
    border-radius: 24px 24px 0 0;
    max-height: 90dvh;
    width: 100%;
    padding: 1.15rem 1.1rem calc(1.25rem + env(safe-area-inset-bottom, 0px));
    border-bottom: none;
  }
}

/* -----------------------------------------------------------------
   TIER 4: Ultra-Compact Phones & Foldables (<= 380px)
   ----------------------------------------------------------------- */
@media (max-width: 380px) {
  .bento-stat-tile {
    flex-wrap: wrap;
  }

  .bento-live-pill,
  .bento-stat-tile > .btn {
    width: 100%;
    text-align: center;
    justify-content: center;
  }

  .nav-tab {
    font-size: 0.62rem;
    min-height: 50px;
  }
}