/* ==========================================================================
   IMAA-OS Custom Styling Sheet
   Aesthetics: Deep Space Dark Mode, Glassmorphic UI, Neon Accents, Fluid Layouts
   ========================================================================== */

/* Design Tokens & Variables */
:root {
  --bg-dark: #07090e;
  --bg-primary: #0c0f17;
  --bg-secondary: #121824;
  --bg-tertiary: #192132;
  --bg-glass: rgba(18, 24, 36, 0.65);
  --border-glass: rgba(255, 255, 255, 0.07);
  
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-white: #ffffff;
  
  --primary: #3b82f6;
  --primary-rgb: 59, 130, 246;
  --purple: #8b5cf6;
  --purple-rgb: 139, 92, 246;
  --pink: #ec4899;
  --pink-rgb: 236, 72, 153;
  --emerald: #10b981;
  --amber: #f59e0b;
  --red: #ef4444;

  --font-heading: 'Outfit', sans-serif;
  --font-body: 'Inter', sans-serif;
  
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  
  --shadow-glow-blue: 0 0 25px rgba(59, 130, 246, 0.3);
  --shadow-glow-purple: 0 0 25px rgba(139, 92, 246, 0.3);
  --shadow-glass: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
  
  --container-width: 1200px;
}

/* Reset & Base Elements */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-dark);
  color: var(--text-secondary);
  line-height: 1.6;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.25;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition-fast);
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
  outline: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Utility Classes */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

.text-center { text-align: center; }
.text-purple { color: var(--purple); }
.w-full { width: 100%; }
.hidden { display: none !important; }

/* Gradient Text Effect */
.gradient-text {
  background: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 50%, #ec4899 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Glow Background Orbs */
.glow-bg-1, .glow-bg-2 {
  position: absolute;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.15) 0%, rgba(59, 130, 246, 0.05) 50%, rgba(0, 0, 0, 0) 70%);
  filter: blur(60px);
  z-index: -10;
  pointer-events: none;
}
.glow-bg-1 {
  top: 10%;
  right: -100px;
}
.glow-bg-2 {
  top: 45%;
  left: -200px;
  background: radial-gradient(circle, rgba(236, 72, 153, 0.12) 0%, rgba(139, 92, 246, 0.04) 60%, rgba(0, 0, 0, 0) 80%);
}

/* Scrollbar Customization */
::-webkit-scrollbar {
  width: 10px;
}
::-webkit-scrollbar-track {
  background: var(--bg-dark);
}
::-webkit-scrollbar-thumb {
  background: var(--bg-tertiary);
  border: 2px solid var(--bg-dark);
  border-radius: 5px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--primary);
}

/* Glassmorphism Cards */
.glass-card {
  background: var(--bg-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-glass);
  transition: var(--transition-normal);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: var(--transition-normal);
}
.btn-primary {
  background: linear-gradient(135deg, var(--primary) 0%, var(--purple) 100%);
  color: var(--text-white);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow-purple);
}
.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-glass);
  color: var(--text-primary);
}
.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  color: var(--text-white);
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}
.btn-glow:hover {
  animation: pulse-glow 2s infinite;
}
.btn-lg {
  padding: 16px 36px;
  font-size: 17px;
  font-weight: 700;
}

@keyframes pulse-glow {
  0% { box-shadow: 0 0 0 0 rgba(139, 92, 246, 0.7); }
  70% { box-shadow: 0 0 0 15px rgba(139, 92, 246, 0); }
  100% { box-shadow: 0 0 0 0 rgba(139, 92, 246, 0); }
}

/* Badge Utility */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  color: #60a5fa;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 20px;
}
.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: #60a5fa;
  animation: blink 1.5s infinite;
}

@keyframes blink {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 1; }
}

/* Header / Navbar */
.navbar-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  padding: 16px 0;
  background: rgba(7, 9, 14, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-glass);
  transition: var(--transition-normal);
}
.navbar-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.navbar-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}
.navbar-logo {
  width: 36px;
  height: 36px;
}
.brand-text {
  font-family: var(--font-heading);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: 1px;
  color: var(--text-primary);
}
.brand-text span {
  color: var(--primary);
}
.navbar-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}
.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 6px 0;
  position: relative;
}
.nav-link:hover, .nav-link.active {
  color: var(--text-primary);
}
.nav-cta {
  background: linear-gradient(135deg, var(--primary) 0%, var(--purple) 100%);
  color: var(--text-white) !important;
  padding: 8px 20px !important;
  border-radius: var(--radius-sm);
}
.nav-cta:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-glow-blue);
}
.nav-toggle {
  display: none;
  color: var(--text-primary);
  font-size: 24px;
}
.nav-toggle .lucide-x {
  display: none;
}
.nav-toggle.active .lucide-menu {
  display: none;
}
.nav-toggle.active .lucide-x {
  display: block;
}

/* Sections Base */
section {
  padding: 100px 0;
  position: relative;
}
.section-header {
  max-width: 600px;
  margin: 0 auto 60px auto;
}
.section-title {
  font-size: 38px;
  margin-bottom: 16px;
}
.section-subtitle {
  font-size: 16px;
  color: var(--text-secondary);
}

/* Hero Section */
.hero-section {
  padding: 160px 0 100px 0;
  overflow: hidden;
}
.hero-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 40px;
}
.hero-content {
  max-width: 580px;
}
.hero-title {
  font-size: 54px;
  line-height: 1.15;
  margin-bottom: 20px;
  letter-spacing: -1px;
}
.hero-subtitle {
  font-size: 18px;
  color: var(--text-secondary);
  margin-bottom: 36px;
}
.hero-actions {
  display: flex;
  gap: 16px;
  margin-bottom: 48px;
}
.hero-stats {
  display: flex;
  gap: 40px;
}
.stat-item {
  display: flex;
  flex-direction: column;
}
.stat-num {
  font-family: var(--font-heading);
  font-size: 28px;
  font-weight: 800;
  color: var(--text-primary);
}
.stat-label {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* Hero Preview (Glassmorphic Mockup) */
.hero-preview {
  position: relative;
  display: flex;
  justify-content: center;
}
.preview-card {
  width: 100%;
  overflow: hidden;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
  animation: float-panel 6s ease-in-out infinite;
}
.preview-header {
  background: rgba(12, 15, 23, 0.6);
  padding: 12px 18px;
  display: flex;
  align-items: center;
  border-bottom: 1px solid var(--border-glass);
}
.preview-dots {
  display: flex;
  gap: 6px;
}
.preview-dots span {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}
.dot-red { background-color: var(--red); }
.dot-yellow { background-color: var(--amber); }
.dot-green { background-color: var(--emerald); }
.preview-title {
  flex-grow: 1;
  text-align: center;
  font-size: 11px;
  color: var(--text-muted);
  letter-spacing: 0.5px;
  padding-right: 28px;
}
.preview-body {
  padding: 0px;
}
.desktop-mockup {
  width: 100%;
  display: block;
  object-fit: cover;
  transition: transform var(--transition-slow);
}
.preview-card:hover .desktop-mockup {
  transform: scale(1.02);
}

@keyframes float-panel {
  0%, 100% { transform: translateY(0px); }
  50% { transform: translateY(-12px); }
}

/* About Section */
.about-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}
.about-card {
  padding: 40px 30px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
}
.about-card:hover {
  transform: translateY(-8px);
  border-color: rgba(255, 255, 255, 0.15);
  box-shadow: 0 12px 40px rgba(0,0,0,0.4);
}
.card-icon-wrapper {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  color: var(--text-primary);
}
.card-icon-wrapper i {
  width: 24px;
  height: 24px;
}
.purple-glow {
  background: rgba(139, 92, 246, 0.1);
  border: 1px solid rgba(139, 92, 246, 0.2);
  color: var(--purple);
}
.blue-glow {
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  color: var(--primary);
}
.pink-glow {
  background: rgba(236, 72, 153, 0.1);
  border: 1px solid rgba(236, 72, 153, 0.2);
  color: var(--pink);
}
.about-card h3 {
  font-size: 20px;
  margin-bottom: 12px;
}
.about-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* App Showcase (Tabs Layout) */
.apps-tabs-container {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 40px;
  align-items: start;
}
.apps-tabs-nav {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.tab-btn {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-size: 15px;
  font-weight: 600;
  text-align: left;
  border: 1px solid transparent;
  background: rgba(255,255,255,0.02);
  transition: var(--transition-normal);
}
.tab-btn i {
  width: 18px;
  height: 18px;
  transition: var(--transition-fast);
}
.tab-btn:hover {
  background: rgba(255,255,255,0.05);
  color: var(--text-primary);
}
.tab-btn.active {
  background: linear-gradient(135deg, rgba(59,130,246,0.15) 0%, rgba(139,92,246,0.15) 100%);
  border-color: rgba(139,92,246,0.3);
  color: var(--text-white);
  box-shadow: 0 4px 20px rgba(139, 92, 246, 0.15);
}
.tab-btn.active i {
  color: var(--purple);
  transform: scale(1.1);
}

.apps-tab-panels {
  min-height: 400px;
}
.tab-panel {
  display: none;
  animation: panel-fade-in 0.4s ease forwards;
}
.tab-panel.active {
  display: block;
}

@keyframes panel-fade-in {
  from { opacity: 0; transform: translateY(15px); }
  to { opacity: 1; transform: translateY(0); }
}

.panel-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 40px;
  align-items: center;
}
.panel-info {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}
.app-tag {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
}
.tag-audio { background: rgba(96, 165, 250, 0.15); color: #60a5fa; }
.tag-design { background: rgba(244, 63, 94, 0.15); color: #fb7185; }
.tag-video { background: rgba(168, 85, 247, 0.15); color: #c084fc; }
.tag-art { background: rgba(236, 72, 153, 0.15); color: #f472b6; }
.tag-office { background: rgba(16, 185, 129, 0.15); color: #34d399; }
.tag-vlc { background: rgba(245, 158, 11, 0.15); color: #fbbf24; }

.panel-info h3 {
  font-size: 32px;
  margin-bottom: 16px;
}
.app-desc {
  font-size: 15px;
  color: var(--text-secondary);
  margin-bottom: 24px;
}
.app-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.app-features li {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 14px;
  color: var(--text-primary);
}
.app-features li i {
  width: 16px;
  height: 16px;
  color: var(--emerald);
}

.panel-media {
  position: relative;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-glass);
  border: 1px solid var(--border-glass);
  cursor: pointer;
}
.app-screenshot {
  width: 100%;
  display: block;
  object-fit: cover;
  transition: transform var(--transition-slow);
}
.media-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(12, 15, 23, 0.7);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  opacity: 0;
  transition: var(--transition-normal);
  z-index: 5;
  color: var(--text-white);
  font-weight: 500;
  font-size: 14px;
}
.media-overlay i {
  width: 24px;
  height: 24px;
}
.panel-media:hover .app-screenshot {
  transform: scale(1.05);
}
.panel-media:hover .media-overlay {
  opacity: 1;
}

/* Gallery Section (Slider) */
.gallery-slider {
  max-width: 900px;
  margin: 0 auto;
  position: relative;
}
.slider-wrapper {
  display: flex;
  overflow: hidden;
  position: relative;
  border-radius: var(--radius-lg);
}
.slide {
  flex: 0 0 100%;
  width: 100%;
  transition: transform var(--transition-slow);
  position: relative;
  padding: 10px;
}
.slide img {
  width: 100%;
  border-radius: var(--radius-md);
  display: block;
  cursor: pointer;
  border: 1px solid var(--border-glass);
  transition: opacity var(--transition-fast);
}
.slide img:hover {
  opacity: 0.9;
}
.slide-label {
  position: absolute;
  top: 24px;
  left: 24px;
  background: rgba(7, 9, 14, 0.75);
  backdrop-filter: blur(8px);
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  font-size: 12px;
  font-weight: 600;
  color: var(--text-primary);
  border: 1px solid var(--border-glass);
  z-index: 2;
}

.slider-controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 24px;
  padding: 0 10px;
}
.slider-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border-glass);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-fast);
}
.slider-btn:hover {
  background: var(--primary);
  color: var(--text-white);
  border-color: var(--primary);
  transform: scale(1.05);
}
.slider-btn i {
  width: 20px;
  height: 20px;
}
.slider-dots {
  display: flex;
  gap: 8px;
}
.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.2);
  transition: var(--transition-fast);
  cursor: pointer;
}
.dot.active {
  background: var(--primary);
  width: 24px;
  border-radius: 4px;
}

/* Requirements & Checker Section */
.requirements-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}
.req-card {
  padding: 40px 30px;
  display: flex;
  flex-direction: column;
}
.req-type {
  font-family: var(--font-heading);
  font-size: 15px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  margin-bottom: 30px;
}
.active-border {
  border-color: rgba(139, 92, 246, 0.4);
  box-shadow: var(--shadow-glow-purple);
  position: relative;
}
.badge-recommended {
  color: var(--purple);
}
.req-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 24px;
}
.req-list li {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}
.req-icon {
  color: var(--primary);
  margin-top: 3px;
}
.req-icon i {
  width: 20px;
  height: 20px;
}
.req-list strong {
  display: block;
  font-size: 15px;
  color: var(--text-primary);
}
.req-list span {
  font-size: 13px;
  color: var(--text-secondary);
}

/* PC Checker Card */
.checker-card {
  border-color: rgba(255,255,255,0.05);
}
.checker-intro {
  font-size: 13px;
  margin-bottom: 24px;
  color: var(--text-secondary);
}
.checker-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  text-align: left;
}
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
.form-group label {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-primary);
}
.form-group select {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  padding: 10px 14px;
  font-size: 13px;
  outline: none;
  transition: var(--transition-fast);
}
.form-group select:focus {
  border-color: var(--primary);
  background: rgba(255, 255, 255, 0.06);
}
.form-group select option {
  background-color: var(--bg-secondary);
  color: var(--text-primary);
}

.checker-result {
  margin-top: 20px;
  text-align: left;
}
.result-divider {
  height: 1px;
  background: var(--border-glass);
  margin-bottom: 20px;
}
.result-status-wrapper {
  display: flex;
  gap: 14px;
  align-items: center;
}
.result-icon-badge {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-white);
  flex-shrink: 0;
}
.result-icon-badge.success {
  background-color: var(--emerald);
}
.result-icon-badge.warning {
  background-color: var(--amber);
}
.result-icon-badge.danger {
  background-color: var(--red);
}
.result-icon-badge i {
  width: 18px;
  height: 18px;
}
.result-title {
  font-size: 15px;
  margin-bottom: 2px;
}
.result-desc {
  font-size: 12px;
  color: var(--text-secondary);
}

/* Download Section & Installation Guide */
.download-section {
  padding-bottom: 120px;
}
.download-box {
  max-width: 800px;
  margin: 0 auto 60px auto;
  padding: 60px 40px;
  position: relative;
  overflow: hidden;
  border-color: rgba(59, 130, 246, 0.2);
  box-shadow: 0 0 40px rgba(59, 130, 246, 0.1);
}
.download-badge {
  display: inline-block;
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: var(--emerald);
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  margin-bottom: 20px;
}
.download-heading {
  font-size: 42px;
  margin-bottom: 16px;
}
.download-subtext {
  font-size: 16px;
  max-width: 550px;
  margin: 0 auto 36px auto;
}
.download-actions-grid {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 30px;
}
.checksum-info {
  font-family: monospace;
  font-size: 12px;
  color: var(--text-muted);
  background: rgba(0, 0, 0, 0.2);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  display: inline-block;
  max-width: 100%;
  overflow-x: auto;
  white-space: nowrap;
}

/* Download progress feedback simulation */
.download-progress-box {
  max-width: 400px;
  margin: 0 auto 24px auto;
  text-align: left;
  animation: panel-fade-in var(--transition-fast) forwards;
}
.progress-details {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 8px;
}
.progress-bar-container {
  height: 6px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: 10px;
}
.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--primary) 0%, var(--purple) 100%);
  border-radius: var(--radius-full);
  transition: width 0.1s ease;
}
.progress-note {
  font-size: 11px;
  color: var(--text-muted);
}

/* Installation Guide Step Cards */
.install-guide {
  max-width: 1000px;
  margin: 0 auto;
}
.guide-title {
  font-size: 24px;
  margin-bottom: 36px;
}
.guide-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.step-card {
  position: relative;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 30px 20px;
  text-align: center;
  transition: var(--transition-normal);
}
.step-card:hover {
  background: rgba(255, 255, 255, 0.04);
  transform: translateY(-4px);
}
.step-num {
  position: absolute;
  top: -16px;
  left: 50%;
  transform: translateX(-50%);
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--bg-tertiary);
  border: 2px solid var(--primary);
  color: var(--primary);
  font-family: var(--font-heading);
  font-size: 14px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}
.step-card h4 {
  font-size: 16px;
  margin-bottom: 8px;
  margin-top: 10px;
}
.step-card p {
  font-size: 12px;
  color: var(--text-secondary);
}

/* Lightbox Modal */
.lightbox-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(7, 9, 14, 0.95);
  backdrop-filter: blur(12px);
  z-index: 1000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 40px;
  opacity: 0;
  transition: opacity var(--transition-normal);
}
.lightbox-modal.active {
  display: flex;
  opacity: 1;
}
.lightbox-close {
  position: absolute;
  top: 24px;
  right: 24px;
  width: 48px;
  height: 48px;
  background: rgba(255,255,255,0.05);
  border-radius: 50%;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-fast);
}
.lightbox-close:hover {
  background: var(--red);
  color: var(--text-white);
}
.lightbox-content {
  max-width: 1100px;
  max-height: 80vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.lightbox-content img {
  max-width: 100%;
  max-height: 70vh;
  border-radius: var(--radius-sm);
  box-shadow: 0 20px 60px rgba(0,0,0,0.8);
  border: 1px solid var(--border-glass);
}
.lightbox-caption {
  font-family: var(--font-heading);
  font-size: 16px;
  color: var(--text-primary);
}

/* Footer Section */
.site-footer {
  background: var(--bg-dark);
  border-top: 1px solid var(--border-glass);
  padding: 80px 0 40px 0;
}
.footer-container {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 60px;
  margin-bottom: 60px;
}
.footer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
  font-family: var(--font-heading);
  font-size: 24px;
  font-weight: 800;
  color: var(--text-primary);
}
.footer-logo {
  width: 40px;
  height: 40px;
}
.footer-about {
  font-size: 14px;
  color: var(--text-secondary);
  max-width: 450px;
}
.footer-links-side {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}
.link-group {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.link-group h4 {
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  margin-bottom: 4px;
}
.link-group a {
  font-size: 14px;
  color: var(--text-secondary);
}
.link-group a:hover {
  color: var(--primary);
  transform: translateX(4px);
}
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.03);
  padding-top: 40px;
}
.footer-bottom-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--text-muted);
}
.ubuntu-attribution {
  max-width: 500px;
  text-align: right;
}

/* ==========================================================================
   Responsive Media Queries (Mobile First approach overrides)
   ========================================================================== */

@media (max-width: 1024px) {
  .hero-container {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 60px;
  }
  .hero-content {
    max-width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
  }
  .hero-actions {
    justify-content: center;
  }
  .hero-stats {
    justify-content: center;
  }
  .about-grid {
    grid-template-columns: 1fr;
  }
  .apps-tabs-container {
    grid-template-columns: 1fr;
  }
  .apps-tabs-nav {
    flex-direction: row;
    overflow-x: auto;
    padding-bottom: 12px;
    margin-bottom: 20px;
    -webkit-overflow-scrolling: touch;
  }
  .tab-btn {
    flex-shrink: 0;
  }
  .panel-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
  .panel-media {
    order: -1;
  }
  .requirements-grid {
    grid-template-columns: 1fr;
  }
  .guide-steps {
    grid-template-columns: 1fr 1fr;
    gap: 30px;
  }
  .footer-container {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

@media (max-width: 768px) {
  .navbar-nav {
    display: none; /* JS will toggle active class */
    position: absolute;
    top: 80px;
    left: 24px;
    right: 24px;
    background: rgba(12, 15, 23, 0.95);
    border: 1px solid var(--border-glass);
    border-radius: var(--radius-md);
    flex-direction: column;
    padding: 30px;
    gap: 20px;
    z-index: 100;
    box-shadow: var(--shadow-glass);
  }
  .navbar-nav.active {
    display: flex;
  }
  .nav-toggle {
    display: block;
  }
  .hero-title {
    font-size: 40px;
  }
  .hero-subtitle {
    font-size: 16px;
  }
  .section-title {
    font-size: 30px;
  }
  .download-box {
    padding: 40px 20px;
  }
  .download-heading {
    font-size: 32px;
  }
  .footer-bottom-container {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
  .ubuntu-attribution {
    text-align: center;
  }
}

@media (max-width: 480px) {
  .hero-actions {
    flex-direction: column;
    width: 100%;
  }
  .hero-actions .btn {
    width: 100%;
  }
  .hero-stats {
    flex-direction: column;
    gap: 20px;
  }
  .apps-tabs-nav {
    padding-bottom: 4px;
  }
  .tab-btn {
    padding: 12px 16px;
    font-size: 13px;
  }
  .guide-steps {
    grid-template-columns: 1fr;
  }
}

/* Spinner Animation Utilities */
.spin {
  animation: spin 1s linear infinite;
  display: inline-block;
}

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