/* ==========================================================================
   Apple Guru - Flagship Digital Experience & Editorial Design System
   Tailored for Chitwan, Nepal | 2026 AEO/GEO/SEO | WCAG 2.1 AA Compliant
   ========================================================================== */

:root {
  /* Core Brand Tokens */
  --brand-primary: #0071E3;
  --brand-primary-hover: #0077ED;
  --brand-glow: rgba(0, 113, 227, 0.4);
  --brand-accent: #2997FF;
  --apple-titanium: #8E8D92;
  --apple-gold: #D4AF37;
  --apple-black: #050505;
  --apple-secondary: #111111;
  --success: #30D158;
  --warning: #FFD60A;
  --danger: #FF453A;

  /* Light Theme Tokens */
  --bg-primary: #F5F5F7;
  --bg-surface: #FFFFFF;
  --bg-surface-elevated: #F9F9FB;
  --bg-surface-glass: rgba(255, 255, 255, 0.88);
  --text-primary: #1D1D1F;
  --text-secondary: #475569;
  --text-muted: #86868B;
  --border-subtle: rgba(0, 0, 0, 0.08);
  --border-medium: rgba(0, 0, 0, 0.16);
  --border-accent: rgba(0, 113, 227, 0.35);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 12px 32px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 24px 64px rgba(0, 0, 0, 0.12);
  --shadow-glow: 0 0 30px rgba(0, 113, 227, 0.2);

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-serif: "Playfair Display", Georgia, serif;
  --font-mono: "SF Mono", Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  
  /* Layout & Animation */
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --radius-full: 9999px;
  --transition-fast: 0.15s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-slow: 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

[data-theme="dark"],
body.dark-theme,
html.dark {
  --bg-primary: #050505;
  --bg-surface: #111114;
  --bg-surface-elevated: #18181C;
  --bg-surface-glass: rgba(17, 17, 20, 0.88);
  --text-primary: #F8FAFC;
  --text-secondary: #94A3B8;
  --text-muted: #64748B;
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-medium: rgba(255, 255, 255, 0.16);
  --border-accent: rgba(41, 151, 255, 0.4);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.5);
  --shadow-md: 0 12px 32px rgba(0, 0, 0, 0.7);
  --shadow-lg: 0 24px 64px rgba(0, 0, 0, 0.85);
  --shadow-glow: 0 0 35px rgba(41, 151, 255, 0.28);
}

/* Base Resets & Global Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background-color var(--transition-smooth), color var(--transition-smooth);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::selection {
  background-color: var(--brand-primary);
  color: #FFFFFF;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--border-medium);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* Reading Progress Bar */
#reading-progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, #0071E3, #2997FF, #30D158);
  z-index: 9999;
  transition: width 0.1s linear;
  box-shadow: 0 0 10px rgba(41, 151, 255, 0.8);
}

/* Glassmorphism Utilities */
.glass-nav {
  background: var(--bg-surface-glass);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border-bottom: 1px solid var(--border-subtle);
}

.glass-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: var(--transition-smooth);
}

.glass-card:hover {
  border-color: var(--border-accent);
  box-shadow: var(--shadow-md), var(--shadow-glow);
  transform: translateY(-3px);
}

.glass-pill {
  background: var(--bg-surface-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
}

/* Typography Gradient Classes */
.text-gradient-titanium {
  background: linear-gradient(135deg, #FFFFFF 0%, #CBD5E1 50%, #64748B 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

[data-theme="light"] .text-gradient-titanium {
  background: linear-gradient(135deg, #0F172A 0%, #334155 60%, #64748B 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-gradient-blue {
  background: linear-gradient(135deg, #2997FF 0%, #0071E3 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-gradient-gold {
  background: linear-gradient(135deg, #F5E7DA 0%, #D4AF37 50%, #997B28 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Custom Interactive 3D Canvas Area */
#three-canvas-container {
  width: 100%;
  height: 460px;
  position: relative;
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: radial-gradient(circle at 50% 50%, rgba(41, 151, 255, 0.1) 0%, rgba(0, 0, 0, 0) 70%);
}

@media (min-width: 768px) {
  #three-canvas-container {
    height: 540px;
  }
}

@media (min-width: 1024px) {
  #three-canvas-container {
    height: 600px;
  }
}

/* 3D Model Hotspot Indicators */
.hotspot-point {
  position: absolute;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: rgba(41, 151, 255, 0.4);
  border: 2px solid #2997FF;
  cursor: pointer;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-fast);
  animation: pulse-ring 2s infinite;
}

.hotspot-point::after {
  content: '';
  width: 8px;
  height: 8px;
  background: #FFFFFF;
  border-radius: 50%;
}

.hotspot-point:hover {
  transform: scale(1.25);
  background: rgba(41, 151, 255, 0.85);
}

@keyframes pulse-ring {
  0% {
    box-shadow: 0 0 0 0 rgba(41, 151, 255, 0.6);
  }
  70% {
    box-shadow: 0 0 0 14px rgba(41, 151, 255, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(41, 151, 255, 0);
  }
}

/* Apple Guru Signature Verification Badge */
.original-seal-badge {
  background: linear-gradient(135deg, rgba(48, 209, 88, 0.12) 0%, rgba(0, 113, 227, 0.12) 100%);
  border: 1px solid rgba(48, 209, 88, 0.35);
  color: #30D158;
}

[data-theme="light"] .original-seal-badge {
  background: linear-gradient(135deg, rgba(40, 167, 69, 0.1) 0%, rgba(0, 113, 227, 0.1) 100%);
  border-color: rgba(40, 167, 69, 0.35);
  color: #1E7E34;
}

/* Buttons System */
.btn-apple-primary {
  background: var(--brand-primary);
  color: #FFFFFF !important;
  font-weight: 600;
  padding: 12px 24px;
  border-radius: var(--radius-full);
  border: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  transition: var(--transition-fast);
  text-decoration: none;
  font-size: 0.9375rem;
  box-shadow: 0 4px 14px rgba(0, 113, 227, 0.3);
}

.btn-apple-primary:hover {
  background: var(--brand-primary-hover);
  transform: translateY(-1px) scale(1.02);
  box-shadow: 0 6px 20px rgba(0, 113, 227, 0.45);
}

.btn-apple-secondary {
  background: var(--bg-surface-elevated);
  color: var(--text-primary) !important;
  font-weight: 500;
  padding: 11px 22px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-medium);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  transition: var(--transition-fast);
  text-decoration: none;
  font-size: 0.9375rem;
}

.btn-apple-secondary:hover {
  background: var(--border-subtle);
  border-color: var(--text-muted);
  transform: translateY(-1px) scale(1.02);
}

.btn-whatsapp-live {
  background: #25D366;
  color: #FFFFFF !important;
  font-weight: 600;
  padding: 12px 24px;
  border-radius: var(--radius-full);
  border: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  transition: var(--transition-fast);
  text-decoration: none;
  box-shadow: 0 4px 14px rgba(37, 211, 102, 0.35);
}

.btn-whatsapp-live:hover {
  background: #20BA5A;
  transform: translateY(-1px) scale(1.02);
  box-shadow: 0 6px 20px rgba(37, 211, 102, 0.5);
}

/* Floating Action Bar */
.floating-bottom-bar {
  position: fixed;
  bottom: 16px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 90;
  width: calc(100% - 24px);
  max-width: 520px;
  box-shadow: var(--shadow-lg), 0 0 24px rgba(0, 0, 0, 0.4);
}

/* Floating WhatsApp Button */
#floating-whatsapp-btn {
  position: fixed;
  bottom: 84px;
  right: 20px;
  z-index: 85;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: #25D366;
  color: #FFFFFF;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  box-shadow: 0 6px 20px rgba(37, 211, 102, 0.45);
  transition: var(--transition-smooth);
  text-decoration: none;
}

#floating-whatsapp-btn:hover {
  transform: scale(1.1) rotate(5deg);
  box-shadow: 0 8px 25px rgba(37, 211, 102, 0.6);
}

@media (min-width: 768px) {
  #floating-whatsapp-btn {
    bottom: 24px;
    right: 24px;
    width: 60px;
    height: 60px;
    font-size: 30px;
  }
}

/* Blog & Article Typography Constraints (ui-ux-pro-max-blog-architect standard) */
.article-prose {
  max-width: 68ch;
  margin-left: auto;
  margin-right: auto;
  font-size: 1.125rem;
  line-height: 1.75;
  color: var(--text-secondary);
}

.article-prose h2 {
  font-size: 1.875rem;
  line-height: 1.25;
  font-weight: 700;
  color: var(--text-primary);
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.article-prose h3 {
  font-size: 1.375rem;
  line-height: 1.35;
  font-weight: 600;
  color: var(--text-primary);
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.article-prose p {
  margin-bottom: 1.5rem;
}

.article-prose ul, .article-prose ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.article-prose li {
  margin-bottom: 0.5rem;
}

.article-prose blockquote {
  border-left: 3px solid var(--brand-primary);
  padding-left: 1.25rem;
  margin: 1.75rem 0;
  font-style: italic;
  color: var(--text-primary);
  background: var(--border-subtle);
  padding: 1rem 1.25rem;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

/* Callout Boxes */
.callout-box {
  border-radius: var(--radius-md);
  padding: 1.25rem;
  margin: 1.5rem 0;
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.callout-info {
  background: rgba(0, 113, 227, 0.08);
  border: 1px solid rgba(0, 113, 227, 0.25);
  color: var(--text-primary);
}

.callout-warning {
  background: rgba(255, 214, 10, 0.08);
  border: 1px solid rgba(255, 214, 10, 0.3);
  color: var(--text-primary);
}

.callout-success {
  background: rgba(48, 209, 88, 0.08);
  border: 1px solid rgba(48, 209, 88, 0.3);
  color: var(--text-primary);
}

/* Device Comparison & Spec Tables */
.apple-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-subtle);
}

.apple-table th {
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  font-weight: 600;
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border-medium);
}

.apple-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

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

.apple-table tr:hover td {
  background: var(--border-subtle);
}

/* FAQ Accordion Styling */
.faq-item {
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  transition: var(--transition-smooth);
}

.faq-item[open] {
  border-color: var(--border-accent);
  box-shadow: var(--shadow-sm);
}

.faq-summary {
  cursor: pointer;
  list-style: none;
  padding: 18px 20px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

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

.faq-content {
  padding: 0 20px 18px 20px;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* Fun Facts Flip Card Utilities */
.flip-card {
  background-color: transparent;
  perspective: 1000px;
}

.flip-card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  text-align: center;
  transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
  transform-style: preserve-3d;
}

.flip-card.flipped .flip-card-inner {
  transform: rotateY(180deg);
}

.flip-card-front, .flip-card-back {
  position: absolute;
  width: 100%;
  height: 100%;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  border-radius: var(--radius-lg);
}

.flip-card-back {
  transform: rotateY(180deg);
}

/* Keyframe Animations */
@keyframes floatUp {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.animate-float {
  animation: floatUp 4s ease-in-out infinite;
}

@keyframes spinSlow {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.animate-spin-slow {
  animation: spinSlow 20s linear infinite;
}