/**
 * AETHERA AEROSPACE ENGINEERING - Global Stylesheet
 * Design Philosophy: Aerospace Minimalism
 * Color System: Vacuum Black (#010103), Titanium Gray (#A8A9AD), Telemetry Cyan (#00EFFF), Orbital Gold (#D4AF37)
 * Typography: Modern sans-serif + Monospace for technical data
 * Layout: Symmetric, modular, orbital geometry
 */

/* ============================================================================
   ROOT VARIABLES & DESIGN TOKENS
   ============================================================================ */

:root {
  /* Primary Color Palette */
  --color-vacuum-black: #010103;
  --color-titanium-gray: #A8A9AD;
  --color-telemetry-cyan: #00EFFF;
  --color-orbital-gold: #D4AF37;
  
  /* Extended Palette */
  --color-deep-space: #0a0e27;
  --color-dark-slate: #1a1f3a;
  --color-light-gray: #e8e9eb;
  --color-white: #ffffff;
  
  /* Semantic Colors */
  --bg-primary: var(--color-vacuum-black);
  --bg-secondary: var(--color-deep-space);
  --text-primary: var(--color-light-gray);
  --text-secondary: var(--color-titanium-gray);
  --accent-primary: var(--color-telemetry-cyan);
  --accent-secondary: var(--color-orbital-gold);
  
  /* Typography */
  --font-display: 'Poppins', 'Segoe UI', sans-serif;
  --font-body: 'Inter', 'Segoe UI', sans-serif;
  --font-mono: 'IBM Plex Mono', 'Courier New', monospace;
  
  /* Spacing Scale (8px base) */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;
  --spacing-3xl: 6rem;
  
  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 239, 255, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 239, 255, 0.1);
  --shadow-lg: 0 12px 32px rgba(0, 239, 255, 0.15);
  --shadow-glow: 0 0 20px rgba(0, 239, 255, 0.3);
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Z-index Scale */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
}

/* ============================================================================
   GLOBAL STYLES
   ============================================================================ */

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

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

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.6;
  letter-spacing: 0.3px;
  overflow-x: hidden;
}

/* ============================================================================
   TYPOGRAPHY
   ============================================================================ */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: 0.5px;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
}

h1 {
  font-size: 3.5rem;
  font-weight: 800;
  letter-spacing: -0.5px;
}

h2 {
  font-size: 2.5rem;
  font-weight: 700;
}

h3 {
  font-size: 1.75rem;
  font-weight: 700;
}

h4 {
  font-size: 1.25rem;
  font-weight: 600;
}

h5 {
  font-size: 1rem;
  font-weight: 600;
}

h6 {
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
}

p {
  margin-bottom: var(--spacing-md);
  font-size: 1rem;
}

.lead {
  font-size: 1.25rem;
  font-weight: 300;
  color: var(--text-secondary);
}

.text-muted {
  color: var(--text-secondary);
}

.text-accent {
  color: var(--accent-primary);
}

.text-gold {
  color: var(--accent-secondary);
}

/* Monospace for technical data */
.mono, code, pre {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  letter-spacing: 0.5px;
}

code {
  background-color: var(--bg-secondary);
  color: var(--accent-primary);
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-sm);
}

/* ============================================================================
   LINKS & BUTTONS
   ============================================================================ */

a {
  color: var(--accent-primary);
  text-decoration: none;
  transition: all var(--transition-fast);
  position: relative;
}

a:hover {
  color: var(--accent-secondary);
  text-shadow: 0 0 10px rgba(0, 239, 255, 0.5);
}

a:active {
  color: var(--accent-primary);
}

/* Button Base Styles */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: 0.75rem 1.5rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1rem;
  border: 2px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-normal);
  text-decoration: none;
  white-space: nowrap;
  user-select: none;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.btn:active {
  transform: translateY(0);
}

/* Button Variants */
.btn-primary {
  background-color: var(--accent-primary);
  color: var(--bg-primary);
  border-color: var(--accent-primary);
}

.btn-primary:hover {
  background-color: transparent;
  color: var(--accent-primary);
  box-shadow: inset 0 0 0 2px var(--accent-primary), var(--shadow-glow);
}

.btn-secondary {
  background-color: transparent;
  color: var(--accent-primary);
  border-color: var(--accent-primary);
}

.btn-secondary:hover {
  background-color: var(--accent-primary);
  color: var(--bg-primary);
}

.btn-gold {
  background-color: var(--accent-secondary);
  color: var(--bg-primary);
  border-color: var(--accent-secondary);
}

.btn-gold:hover {
  background-color: transparent;
  color: var(--accent-secondary);
  border-color: var(--accent-secondary);
  box-shadow: inset 0 0 0 2px var(--accent-secondary);
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
}

/* ============================================================================
   NAVIGATION BAR
   ============================================================================ */

.navbar {
  background-color: var(--bg-secondary);
  border-bottom: 1px solid rgba(0, 239, 255, 0.1);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  backdrop-filter: blur(10px);
  background-color: rgba(10, 14, 39, 0.95);
}

.navbar-brand {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--accent-primary);
  text-decoration: none;
  letter-spacing: 1px;
  transition: all var(--transition-fast);
}

.navbar-brand:hover {
  color: var(--accent-secondary);
  text-shadow: 0 0 15px rgba(0, 239, 255, 0.6);
}

.navbar-nav {
  list-style: none;
  display: flex;
  gap: 2rem;
  align-items: center;
}

.nav-link {
  color: var(--text-primary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  position: relative;
  transition: all var(--transition-fast);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--accent-primary);
  transition: width var(--transition-normal);
}

.nav-link:hover {
  color: var(--accent-primary);
}

.nav-link:hover::after {
  width: 100%;
}

.nav-link.active {
  color: var(--accent-primary);
}

.nav-link.active::after {
  width: 100%;
}

/* ============================================================================
   HERO SECTION
   ============================================================================ */

.hero-section {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--color-dark-slate) 100%);
  overflow: hidden;
}

.hero-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 50%, rgba(0, 239, 255, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 80%, rgba(212, 175, 55, 0.05) 0%, transparent 50%);
  pointer-events: none;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(to bottom, transparent 0%, rgba(1, 1, 3, 0.3) 100%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 10;
  text-align: center;
  max-width: 900px;
  padding: var(--spacing-2xl);
  animation: fadeInUp 1s ease-out;
}

.hero-content h1 {
  font-size: 4rem;
  margin-bottom: var(--spacing-lg);
  background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: slideDown 1s ease-out;
}

.hero-content .lead {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-2xl);
  animation: slideUp 1s ease-out 0.2s both;
}

.hero-cta {
  display: flex;
  gap: var(--spacing-lg);
  justify-content: center;
  flex-wrap: wrap;
  animation: slideUp 1s ease-out 0.4s both;
}

/* ============================================================================
   CARDS & MODULES
   ============================================================================ */

.card {
  background-color: var(--bg-secondary);
  border: 1px solid rgba(0, 239, 255, 0.2);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(0, 239, 255, 0.1), transparent);
  transition: left var(--transition-slow);
  pointer-events: none;
}

.card:hover {
  border-color: var(--accent-primary);
  box-shadow: var(--shadow-lg), inset 0 0 20px rgba(0, 239, 255, 0.05);
  transform: translateY(-4px);
}

.card:hover::before {
  left: 100%;
}

.card-header {
  margin-bottom: var(--spacing-md);
  padding-bottom: var(--spacing-md);
  border-bottom: 1px solid rgba(0, 239, 255, 0.1);
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent-primary);
  margin: 0;
}

.card-body {
  margin-bottom: var(--spacing-md);
}

.card-body p {
  margin-bottom: var(--spacing-sm);
  line-height: 1.8;
}

.card-footer {
  padding-top: var(--spacing-md);
  border-top: 1px solid rgba(0, 239, 255, 0.1);
  display: flex;
  gap: var(--spacing-md);
}

/* ============================================================================
   GRID & LAYOUT
   ============================================================================ */

.container {
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-2xl);
}

.row.row-2 {
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
}

.row.row-3 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.col {
  display: flex;
  flex-direction: column;
}

/* ============================================================================
   SECTIONS
   ============================================================================ */

section {
  padding: var(--spacing-3xl) 0;
  position: relative;
}

section.section-dark {
  background-color: var(--bg-primary);
}

section.section-secondary {
  background-color: var(--bg-secondary);
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
}

.section-title h2 {
  position: relative;
  display: inline-block;
  padding-bottom: var(--spacing-md);
}

.section-title h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--accent-primary), transparent);
}

.section-subtitle {
  text-align: center;
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: var(--spacing-2xl);
}

/* ============================================================================
   ANIMATIONS
   ============================================================================ */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-50px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(50px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

@keyframes glow {
  0%, 100% {
    box-shadow: 0 0 10px rgba(0, 239, 255, 0.3);
  }
  50% {
    box-shadow: 0 0 20px rgba(0, 239, 255, 0.6);
  }
}

@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

/* ============================================================================
   UTILITY CLASSES
   ============================================================================ */

.text-center {
  text-align: center;
}

.text-left {
  text-align: left;
}

.text-right {
  text-align: right;
}

.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mt-4 { margin-top: var(--spacing-xl); }

.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }
.mb-4 { margin-bottom: var(--spacing-xl); }

.pt-1 { padding-top: var(--spacing-sm); }
.pt-2 { padding-top: var(--spacing-md); }
.pt-3 { padding-top: var(--spacing-lg); }
.pt-4 { padding-top: var(--spacing-xl); }

.pb-1 { padding-bottom: var(--spacing-sm); }
.pb-2 { padding-bottom: var(--spacing-md); }
.pb-3 { padding-bottom: var(--spacing-lg); }
.pb-4 { padding-bottom: var(--spacing-xl); }

.px-1 { padding-left: var(--spacing-sm); padding-right: var(--spacing-sm); }
.px-2 { padding-left: var(--spacing-md); padding-right: var(--spacing-md); }
.px-3 { padding-left: var(--spacing-lg); padding-right: var(--spacing-lg); }

.py-1 { padding-top: var(--spacing-sm); padding-bottom: var(--spacing-sm); }
.py-2 { padding-top: var(--spacing-md); padding-bottom: var(--spacing-md); }
.py-3 { padding-top: var(--spacing-lg); padding-bottom: var(--spacing-lg); }

.opacity-50 { opacity: 0.5; }
.opacity-75 { opacity: 0.75; }

.hidden { display: none !important; }
.visible { display: block !important; }

/* ============================================================================
   FOOTER
   ============================================================================ */

footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid rgba(0, 239, 255, 0.1);
  padding: var(--spacing-2xl) 0;
  margin-top: var(--spacing-3xl);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-2xl);
}

.footer-section h5 {
  color: var(--accent-primary);
  margin-bottom: var(--spacing-md);
}

.footer-section ul {
  list-style: none;
}

.footer-section li {
  margin-bottom: var(--spacing-sm);
}

.footer-section a {
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.footer-section a:hover {
  color: var(--accent-primary);
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-lg);
  border-top: 1px solid rgba(0, 239, 255, 0.1);
  color: var(--text-secondary);
  font-size: 0.875rem;
}

/* ============================================================================
   RESPONSIVE DESIGN
   ============================================================================ */

@media (max-width: 768px) {
  :root {
    font-size: 14px;
  }

  h1 {
    font-size: 2.5rem;
  }

  h2 {
    font-size: 1.75rem;
  }

  h3 {
    font-size: 1.25rem;
  }

  .hero-content h1 {
    font-size: 2.5rem;
  }

  .hero-content .lead {
    font-size: 1.1rem;
  }

  .hero-cta {
    flex-direction: column;
    align-items: center;
  }

  .navbar-nav {
    gap: 1rem;
    flex-direction: column;
    align-items: flex-start;
  }

  .row {
    grid-template-columns: 1fr;
  }

  .row.row-2 {
    grid-template-columns: 1fr;
  }

  section {
    padding: var(--spacing-2xl) 0;
  }

  .container {
    padding: 0 var(--spacing-md);
  }
}

@media (max-width: 480px) {
  :root {
    font-size: 13px;
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  .hero-section {
    min-height: 70vh;
  }

  .hero-content {
    padding: var(--spacing-lg);
  }

  .hero-content h1 {
    font-size: 1.75rem;
  }

  .btn {
    padding: 0.625rem 1.25rem;
    font-size: 0.875rem;
  }

  .card {
    padding: var(--spacing-md);
  }
}

/* ============================================================================
   SCROLLBAR STYLING
   ============================================================================ */

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--accent-primary);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent-secondary);
}

/* ============================================================================
   PRINT STYLES
   ============================================================================ */

@media print {
  body {
    background-color: white;
    color: black;
  }

  .navbar, footer {
    display: none;
  }

  a {
    color: black;
    text-decoration: underline;
  }
}