/* ========================================
   SUBTERRANEAN SOVEREIGNTY & CRUSTAL SANCTUARY AUTHORITY
   Design System: Subterranean Brutalism
   ======================================== */

/* ========================================
   CSS VARIABLES - DESIGN TOKENS
   ======================================== */
:root {
  /* Core Color Palette */
  --color-obsidian: #121212;           /* 地核黑曜岩 - Main background */
  --color-lava: #FF4500;               /* 熔岩核心橙 - Accent/Alert */
  --color-titanium: #555555;           /* 鈦金屬冷灰 - Structure */
  --color-biolume: #2ECC71;            /* 生物發光苔綠 - Life systems */
  
  /* Extended Palette */
  --color-obsidian-light: #1a1a1a;     /* Lighter obsidian for depth */
  --color-obsidian-lighter: #2a2a2a;   /* Even lighter for contrast */
  --color-lava-dark: #cc3700;          /* Darker lava for hover states */
  --color-titanium-light: #777777;     /* Lighter titanium */
  --color-biolume-dark: #27ae60;       /* Darker biolume */
  --color-white: #ffffff;
  --color-gray-light: #e0e0e0;
  --color-gray-medium: #999999;
  
  /* Typography */
  --font-display: 'Roboto Condensed', 'Arial Black', sans-serif;
  --font-body: 'Roboto', 'Arial', sans-serif;
  --font-mono: 'Courier New', monospace;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  --spacing-4xl: 6rem;
  
  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.5);
  --shadow-xl: 0 12px 24px rgba(0, 0, 0, 0.6);
  --shadow-lava: 0 0 20px rgba(255, 69, 0, 0.3);
  
  /* Border Radius */
  --radius-none: 0;
  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 8px;
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 300ms ease-in-out;
  --transition-slow: 500ms ease-in-out;
}

/* ========================================
   RESET & BASE STYLES
   ======================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--color-obsidian);
  color: var(--color-white);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  font-weight: 400;
  overflow-x: hidden;
}

/* ========================================
   TYPOGRAPHY
   ======================================== */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: 0.5px;
  margin-bottom: var(--spacing-lg);
  text-transform: uppercase;
  line-height: 1.2;
}

h1 {
  font-size: 3.5rem;
  letter-spacing: 2px;
}

h2 {
  font-size: 2.5rem;
  letter-spacing: 1.5px;
}

h3 {
  font-size: 1.75rem;
  letter-spacing: 1px;
}

h4 {
  font-size: 1.25rem;
  letter-spacing: 0.75px;
}

h5 {
  font-size: 1rem;
  letter-spacing: 0.5px;
}

h6 {
  font-size: 0.875rem;
  letter-spacing: 0.5px;
}

p {
  margin-bottom: var(--spacing-md);
  font-size: 1rem;
  line-height: 1.8;
}

a {
  color: var(--color-lava);
  text-decoration: none;
  transition: color var(--transition-fast);
  border-bottom: 1px solid transparent;
}

a:hover {
  color: var(--color-lava-dark);
  border-bottom-color: var(--color-lava);
}

/* ========================================
   NAVBAR STYLES
   ======================================== */
.navbar {
  background-color: var(--color-obsidian-light);
  border-bottom: 2px solid var(--color-titanium);
  padding: var(--spacing-md) var(--spacing-lg);
  box-shadow: var(--shadow-md);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar-brand {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-lava) !important;
  text-transform: uppercase;
  letter-spacing: 1px;
  transition: color var(--transition-fast);
}

.navbar-brand:hover {
  color: var(--color-biolume) !important;
}

.navbar-nav .nav-link {
  color: var(--color-gray-light) !important;
  font-family: var(--font-display);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin: 0 var(--spacing-md);
  transition: all var(--transition-fast);
  position: relative;
  padding-bottom: var(--spacing-sm) !important;
}

.navbar-nav .nav-link:hover,
.navbar-nav .nav-link.active {
  color: var(--color-lava) !important;
}

.navbar-nav .nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-lava);
  transition: width var(--transition-fast);
}

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

.navbar-toggler {
  border-color: var(--color-lava);
}

.navbar-toggler-icon {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='%23FF4500' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
}

/* ========================================
   HERO SECTION & PARALLAX
   ======================================== */
.hero-section {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background: linear-gradient(135deg, var(--color-obsidian) 0%, var(--color-obsidian-lighter) 100%);
}

.hero-background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: 
    linear-gradient(45deg, transparent 48%, var(--color-titanium) 49%, var(--color-titanium) 51%, transparent 52%),
    linear-gradient(-45deg, transparent 48%, var(--color-titanium) 49%, var(--color-titanium) 51%, transparent 52%);
  background-size: 100px 100px;
  opacity: 0.05;
  z-index: 0;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at 50% 50%, rgba(255, 69, 0, 0.1) 0%, transparent 70%);
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 900px;
  padding: var(--spacing-3xl);
}

.hero-content h1 {
  font-size: 4rem;
  margin-bottom: var(--spacing-lg);
  text-shadow: 0 4px 20px rgba(255, 69, 0, 0.3);
  animation: fadeInDown 1s ease-out;
}

.hero-content .slogan {
  font-size: 1.5rem;
  color: var(--color-lava);
  margin-bottom: var(--spacing-2xl);
  font-style: italic;
  animation: fadeInUp 1s ease-out 0.3s both;
}

.hero-content p {
  font-size: 1.1rem;
  color: var(--color-gray-light);
  margin-bottom: var(--spacing-2xl);
  animation: fadeInUp 1s ease-out 0.6s both;
}

.cta-button {
  display: inline-block;
  padding: var(--spacing-md) var(--spacing-2xl);
  background-color: var(--color-lava);
  color: var(--color-white);
  text-transform: uppercase;
  font-family: var(--font-display);
  font-size: 0.875rem;
  letter-spacing: 1px;
  border: 2px solid var(--color-lava);
  border-radius: var(--radius-sm);
  transition: all var(--transition-normal);
  cursor: pointer;
  font-weight: 700;
  box-shadow: var(--shadow-lava);
  animation: fadeInUp 1s ease-out 0.9s both;
}

.cta-button:hover {
  background-color: transparent;
  color: var(--color-lava);
  box-shadow: 0 0 30px rgba(255, 69, 0, 0.5);
  transform: translateY(-2px);
}

/* ========================================
   SECTION STYLES
   ======================================== */
section {
  padding: var(--spacing-4xl) var(--spacing-lg);
  position: relative;
}

section.dark-section {
  background-color: var(--color-obsidian);
  border-top: 2px solid var(--color-titanium);
  border-bottom: 2px solid var(--color-titanium);
}

section.light-section {
  background-color: var(--color-obsidian-lighter);
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
  position: relative;
  padding-bottom: var(--spacing-lg);
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100px;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--color-lava), transparent);
}

/* ========================================
   CARD STYLES
   ======================================== */
.card {
  background-color: var(--color-obsidian-lighter);
  border: 1px solid var(--color-titanium);
  border-radius: var(--radius-md);
  padding: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-md);
}

.card:hover {
  border-color: var(--color-lava);
  box-shadow: 0 0 20px rgba(255, 69, 0, 0.2);
  transform: translateY(-4px);
}

.card-title {
  color: var(--color-lava);
  margin-bottom: var(--spacing-md);
  font-size: 1.25rem;
}

.card-text {
  color: var(--color-gray-light);
  font-size: 0.95rem;
  line-height: 1.8;
}

/* ========================================
   GRID LAYOUT
   ======================================== */
.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-2xl);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-2xl);
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-2xl);
}

@media (max-width: 768px) {
  .grid-4, .grid-3, .grid-2 {
    grid-template-columns: 1fr;
  }
}

/* ========================================
   TECHNICAL SPEC CARD
   ======================================== */
.spec-card {
  background-color: var(--color-obsidian);
  border-left: 4px solid var(--color-lava);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  border-radius: var(--radius-md);
}

.spec-label {
  color: var(--color-biolume);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: var(--spacing-sm);
}

.spec-value {
  color: var(--color-white);
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 700;
}

/* ========================================
   CONTENT SECTION WITH SIDEBAR
   ======================================== */
.content-with-sidebar {
  display: grid;
  grid-template-columns: 1fr 350px;
  gap: var(--spacing-2xl);
}

.sidebar {
  background-color: var(--color-obsidian-lighter);
  border: 1px solid var(--color-titanium);
  padding: var(--spacing-xl);
  border-radius: var(--radius-md);
  height: fit-content;
  position: sticky;
  top: 100px;
}

.sidebar-title {
  color: var(--color-lava);
  font-size: 1.1rem;
  margin-bottom: var(--spacing-lg);
  text-transform: uppercase;
  font-family: var(--font-display);
}

.sidebar-item {
  padding: var(--spacing-md) 0;
  border-bottom: 1px solid var(--color-titanium);
  transition: all var(--transition-fast);
}

.sidebar-item:last-child {
  border-bottom: none;
}

.sidebar-item a {
  color: var(--color-gray-light);
  display: block;
  transition: all var(--transition-fast);
}

.sidebar-item a:hover {
  color: var(--color-lava);
  padding-left: var(--spacing-md);
}

@media (max-width: 1024px) {
  .content-with-sidebar {
    grid-template-columns: 1fr;
  }
  
  .sidebar {
    position: static;
  }
}

/* ========================================
   FOOTER STYLES
   ======================================== */
footer {
  background-color: var(--color-obsidian-light);
  border-top: 2px solid var(--color-titanium);
  padding: var(--spacing-3xl) var(--spacing-lg);
  margin-top: var(--spacing-4xl);
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-2xl);
}

.footer-section h4 {
  color: var(--color-lava);
  margin-bottom: var(--spacing-lg);
}

.footer-section p, .footer-section a {
  color: var(--color-gray-light);
  font-size: 0.95rem;
  margin-bottom: var(--spacing-md);
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-titanium);
  color: var(--color-titanium);
  font-size: 0.85rem;
}

/* ========================================
   ANIMATIONS
   ======================================== */
@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInUp {
  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(255, 69, 0, 0.3);
  }
  50% {
    box-shadow: 0 0 20px rgba(255, 69, 0, 0.6);
  }
}

/* ========================================
   UTILITY CLASSES
   ======================================== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

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

.text-lava {
  color: var(--color-lava);
}

.text-biolume {
  color: var(--color-biolume);
}

.text-titanium {
  color: var(--color-titanium);
}

.text-light {
  color: var(--color-gray-light);
}

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

.bg-obsidian-lighter {
  background-color: var(--color-obsidian-lighter);
}

.border-lava {
  border-color: var(--color-lava);
}

.border-titanium {
  border-color: var(--color-titanium);
}

.mt-lg {
  margin-top: var(--spacing-lg);
}

.mb-lg {
  margin-bottom: var(--spacing-lg);
}

.mt-xl {
  margin-top: var(--spacing-xl);
}

.mb-xl {
  margin-bottom: var(--spacing-xl);
}

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

.p-xl {
  padding: var(--spacing-xl);
}

/* ========================================
   RESPONSIVE DESIGN
   ======================================== */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.5rem;
  }
  
  h3 {
    font-size: 1.25rem;
  }
  
  .hero-content h1 {
    font-size: 2rem;
  }
  
  .hero-content .slogan {
    font-size: 1.1rem;
  }
  
  section {
    padding: var(--spacing-2xl) var(--spacing-md);
  }
  
  .navbar {
    padding: var(--spacing-md);
  }
  
  .navbar-brand {
    font-size: 1.25rem;
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: 1.5rem;
  }
  
  h2 {
    font-size: 1.25rem;
  }
  
  .hero-content {
    padding: var(--spacing-lg);
  }
  
  .hero-content h1 {
    font-size: 1.5rem;
  }
  
  .hero-content .slogan {
    font-size: 1rem;
  }
  
  .cta-button {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 0.75rem;
  }
}