/* ===================================
   MoeNet LLC - Style System
   Tech Stack: Vanilla CSS with Custom Properties
   Features: Light/Dark theme, Responsive, i18n ready
   =================================== */

/* ===== CSS Custom Properties ===== */
:root {
  /* Colors - Light Mode */
  --color-primary: #3b82f6;
  --color-primary-hover: #2563eb;
  --color-accent: #06b6d4;
  
  /* Background */
  --bg-gradient: linear-gradient(180deg, #e8f4ff 0%, #f0e6ff 50%, #e8f4ff 100%);
  --bg-navbar: rgba(255, 255, 255, 0.8);
  --bg-card: rgba(255, 255, 255, 0.6);
  
  /* Text */
  --text-primary: #1a1a2e;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  
  /* Borders & Shadows */
  --border-color: rgba(0, 0, 0, 0.1);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  
  /* Spacing */
  --nav-height: 80px;
  --container-max: 1200px;
  --container-padding: 24px;
  
  /* Animation */
  --transition-fast: 150ms ease;
  --transition-normal: 300ms ease;
  --transition-slow: 500ms ease;
  
  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  --font-size-6xl: 3.75rem;
}

/* Dark Mode */
[data-theme="dark"] {
  --bg-gradient: linear-gradient(180deg, #0f172a 0%, #1e3a5f 50%, #0f172a 100%);
  --bg-navbar: rgba(15, 23, 42, 0.8);
  --bg-card: rgba(30, 41, 59, 0.6);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --border-color: rgba(255, 255, 255, 0.1);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4);
}

/* Auto Dark Mode (System Preference) */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg-gradient: linear-gradient(180deg, #0f172a 0%, #1e3a5f 50%, #0f172a 100%);
    --bg-navbar: rgba(15, 23, 42, 0.8);
    --bg-card: rgba(30, 41, 59, 0.6);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --border-color: rgba(255, 255, 255, 0.1);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4);
  }
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-gradient);
  min-height: 100vh;
  transition: background var(--transition-normal), color var(--transition-normal);
}

a {
  color: inherit;
  text-decoration: none;
}

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

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

/* ===== Navigation ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--bg-navbar);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  transition: background var(--transition-normal), box-shadow var(--transition-normal);
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
}

.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
}

.logo-img {
  height: 48px;
  width: auto;
  transition: transform var(--transition-fast);
}

.logo:hover .logo-img {
  transform: scale(1.05);
}

.nav-links {
  display: flex;
  gap: 32px;
}

.nav-links a {
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
  position: relative;
}

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

.nav-links a:hover {
  color: var(--text-primary);
}

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

.nav-controls {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* Theme Toggle */
.theme-toggle {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: background var(--transition-fast), color var(--transition-fast);
}

.theme-toggle:hover {
  background: var(--bg-card);
  color: var(--text-primary);
}

.icon-sun, .icon-moon {
  transition: opacity var(--transition-fast), transform var(--transition-fast);
}

/* Light mode: show sun */
.icon-moon { display: none; }

/* Dark mode: show moon */
[data-theme="dark"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: block; }

/* Auto dark mode */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .icon-sun { display: none; }
  :root:not([data-theme="light"]) .icon-moon { display: block; }
}

/* Language Dropdown */
.lang-dropdown {
  position: relative;
}

.lang-btn {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 8px 12px;
  border-radius: 8px;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  transition: all var(--transition-fast);
}

.lang-btn:hover {
  color: var(--text-primary);
  border-color: var(--color-primary);
}

.lang-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  min-width: 120px;
  background: var(--bg-navbar);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: all var(--transition-fast);
}

.lang-menu.open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.lang-menu button {
  width: 100%;
  padding: 10px 16px;
  text-align: left;
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.lang-menu button:hover {
  background: var(--bg-card);
  color: var(--text-primary);
}

.lang-menu button:first-child {
  border-radius: 8px 8px 0 0;
}

.lang-menu button:last-child {
  border-radius: 0 0 8px 8px;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 8px;
}

.mobile-menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all var(--transition-fast);
}

.mobile-menu-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* Mobile Navigation */
.mobile-nav {
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  background: var(--bg-navbar);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  padding: 16px var(--container-padding);
  transform: translateY(-100%);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
  z-index: 999;
}

.mobile-nav.open {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

.mobile-nav-links {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mobile-nav-links a {
  font-size: var(--font-size-lg);
  font-weight: 500;
  color: var(--text-secondary);
  padding: 8px 0;
  transition: color var(--transition-fast);
}

.mobile-nav-links a:hover {
  color: var(--text-primary);
}

/* ===== Hero Section ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: calc(var(--nav-height) + 48px) var(--container-padding) 48px;
}

.hero-content {
  max-width: 800px;
  animation: fadeInUp 0.8s ease-out;
}

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

.hero-title {
  font-size: clamp(var(--font-size-3xl), 5vw, var(--font-size-6xl));
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 24px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(var(--font-size-base), 2vw, var(--font-size-xl));
  color: var(--text-secondary);
  margin-bottom: 40px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.cta-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 16px 32px;
  font-size: var(--font-size-base);
  font-weight: 600;
  color: white;
  background: var(--color-primary);
  border-radius: 12px;
  box-shadow: var(--shadow-md), 0 0 0 0 rgba(59, 130, 246, 0.5);
  transition: all var(--transition-fast);
}

.cta-button:hover {
  background: var(--color-primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg), 0 0 20px rgba(59, 130, 246, 0.3);
}

/* ===== Stats Section ===== */
.stats {
  padding: 80px var(--container-padding);
  border-top: 1px solid var(--border-color);
}

.stats-container {
  max-width: var(--container-max);
  margin: 0 auto;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 48px;
  flex-wrap: wrap;
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.stat-number {
  font-size: clamp(var(--font-size-2xl), 4vw, var(--font-size-5xl));
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.stat-label {
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.stat-divider {
  width: 1px;
  height: 60px;
  background: var(--border-color);
}

/* ===== Mission Section ===== */
.mission {
  padding: 80px var(--container-padding);
  min-height: 0; /* Collapse when empty */
}

/* ===== Footer ===== */
.footer {
  padding: 32px var(--container-padding);
  text-align: center;
  border-top: 1px solid var(--border-color);
}

.footer p {
  font-size: var(--font-size-sm);
  color: var(--text-muted);
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
  :root {
    --nav-height: 64px;
    --container-padding: 16px;
  }
  
  .nav-links {
    display: none;
  }
  
  .mobile-menu-toggle {
    display: flex;
  }
  
  .logo-img {
    height: 40px;
  }
  
  .stats-container {
    flex-direction: column;
    gap: 32px;
  }
  
  .stat-divider {
    width: 60px;
    height: 1px;
  }
  
  .hero {
    padding-top: calc(var(--nav-height) + 32px);
  }
}

@media (max-width: 480px) {
  .nav-controls {
    gap: 8px;
  }
  
  .lang-btn {
    padding: 6px 10px;
  }
  
  .theme-toggle {
    width: 36px;
    height: 36px;
  }
}