:root {
  /* Default Dark Theme (Enterprise Developer focused) */
  --bg-color: #050505;
  --bg-alt: #111111;
  --text-color: #f0f0f0;
  --text-muted: #a0a0a0;
  --primary-color: #d90429;
  --primary-hover: #99252e;
  --secondary-color: #222222;
  --secondary-hover: #333333;
  --border-color: #333;
  --nav-bg: rgba(5, 5, 5, 0.8);
  --glass-border: rgba(255, 255, 255, 0.1);
}

.theme-light {
  /* Light Theme */
  --bg-color: #ffffff;
  --bg-alt: #f7f7f7;
  --text-color: #111111;
  --text-muted: #666666;
  --primary-color: #d90429;
  --primary-hover: #99252e;
  --secondary-color: #eaeaea;
  --secondary-hover: #d4d4d4;
  --border-color: #eaeaea;
  --nav-bg: rgba(255, 255, 255, 0.8);
  --glass-border: rgba(0, 0, 0, 0.1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
  transition: background-color 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--primary-hover);
}

ul {
  list-style: none;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--primary-color);
  color: #fff;
  padding: 8px;
  z-index: 1000;
  transition: top 0.2s;
}

.skip-link:focus {
  top: 0;
}

/* Header */
.main-header {
  position: fixed;
  top: 0;
  width: 100%;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: var(--nav-bg);
  border-bottom: 1px solid var(--border-color);
  z-index: 999;
  height: 70px;
  display: flex;
  align-items: center;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-color);
}

.brand:hover {
  color: var(--text-color);
}

.mcc-logo {
  width: 32px;
  height: 32px;
}

.nav-list {
  display: flex;
  gap: 24px;
}

.nav-list a {
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
}

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

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

.lang-switcher select {
  background: transparent;
  color: var(--text-color);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  padding: 4px 8px;
  font-family: inherit;
  font-size: 0.9rem;
  cursor: pointer;
}

#theme-toggle {
  background: transparent;
  border: none;
  color: var(--text-color);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8px;
  border-radius: 50%;
  transition: background 0.2s ease;
}

#theme-toggle:hover {
  background: var(--secondary-color);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 1px solid transparent;
}

.btn-primary {
  background-color: var(--primary-color);
  color: #fff;
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  color: #fff;
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: var(--secondary-color);
  color: var(--text-color);
  border-color: var(--border-color);
}

.btn-secondary:hover {
  background-color: var(--secondary-hover);
  color: var(--text-color);
}

.btn-outline {
  background-color: transparent;
  color: var(--text-color);
  border-color: var(--border-color);
}

.btn-outline:hover {
  background-color: var(--secondary-color);
  color: var(--text-color);
}

/* Layout Utilities */
.section {
  padding: 6rem 0;
}

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

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 3rem;
  text-align: center;
  letter-spacing: -0.02em;
}

.section-subtitle {
  text-align: center;
  margin-top: -2rem;
  margin-bottom: 3rem;
  color: var(--text-muted);
  font-size: 1.2rem;
}

/* Hero Section */
.hero-section {
  position: relative;
  min-height: 90vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding-top: 70px;
  overflow: hidden;
}

.hero-bg-animation {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: radial-gradient(circle at 50% 50%, rgba(217, 4, 41, 0.15), transparent 60%);
  z-index: -1;
  animation: pulseBg 10s infinite alternate;
}

@keyframes pulseBg {
  0% { transform: scale(1); opacity: 0.8; }
  100% { transform: scale(1.1); opacity: 1; }
}

.hero-content {
  max-width: 800px;
}

.hero-title {
  font-size: 5rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  margin-bottom: 1.5rem;
  background: linear-gradient(180deg, var(--text-color) 0%, var(--text-muted) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  opacity: 0;
  animation: fadeInUp 0.8s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
}

.hero-subtitle {
  font-size: 1.5rem;
  color: var(--text-muted);
  margin-bottom: 3rem;
  font-weight: 400;
  opacity: 0;
  animation: fadeInUp 0.8s cubic-bezier(0.2, 0.8, 0.2, 1) 0.15s forwards;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  opacity: 0;
  animation: fadeInUp 0.8s cubic-bezier(0.2, 0.8, 0.2, 1) 0.3s forwards;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.feature-card {
  background: var(--bg-color);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  padding: 2rem;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  border-color: var(--primary-color);
}

.feature-card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
}

.feature-card p {
  color: var(--text-muted);
}

/* Architecture */
.arch-diagram {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.arch-layer {
  width: 100%;
  max-width: 600px;
  padding: 1.5rem;
  border-radius: 8px;
  text-align: center;
  font-weight: 600;
  font-size: 1.2rem;
  border: 1px solid var(--border-color);
}

.arch-layer.core-layer {
  background: rgba(217, 4, 41, 0.1);
  border-color: var(--primary-color);
}

.arch-layer.platform-layer { background: var(--secondary-color); }
.arch-layer.apps-layer { background: var(--secondary-color); }
.arch-layer.editions-layer { background: var(--secondary-color); }

.arrow {
  border: none;
  font-size: 1.5rem;
  color: var(--text-muted);
  padding: 0;
}

/* Editions */
.editions-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
}

.edition-card {
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 2rem;
  background: var(--bg-alt);
}

.edition-card.featured {
  border-color: var(--primary-color);
  background: rgba(217, 4, 41, 0.05);
}

.edition-card h3 {
  font-size: 1.4rem;
  margin-bottom: 1rem;
}

.edition-card p {
  color: var(--text-muted);
}

/* Developer Tags */
.tool-tags {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  max-width: 800px;
  margin: 0 auto;
}

.tool-tag {
  background: var(--secondary-color);
  padding: 0.5rem 1rem;
  border-radius: 20px;
  font-size: 0.9rem;
  font-weight: 500;
  border: 1px solid var(--border-color);
}

/* Split Layout */
.split-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.split-content h2 {
  font-size: 2.5rem;
  margin-bottom: 1.5rem;
}

.split-content p {
  margin-bottom: 2rem;
  font-size: 1.1rem;
  color: var(--text-muted);
}

.check-list li {
  position: relative;
  padding-left: 2rem;
  margin-bottom: 1rem;
  font-weight: 500;
}

.check-list li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--primary-color);
  font-weight: bold;
}

.mock-container {
  background: var(--secondary-color);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  height: 350px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
}

/* Timeline */
.timeline {
  max-width: 800px;
  margin: 0 auto;
  position: relative;
  padding-left: 2rem;
  border-left: 2px solid var(--border-color);
}

.timeline-item {
  position: relative;
  margin-bottom: 3rem;
}

.timeline-item:last-child {
  margin-bottom: 0;
}

.timeline-dot {
  position: absolute;
  left: -2.4rem;
  top: 0.25rem;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--border-color);
  border: 4px solid var(--bg-color);
}

.timeline-item.active .timeline-dot {
  background: var(--primary-color);
}

.timeline-item h3 {
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
}

.timeline-item p {
  color: var(--text-muted);
}

/* Footer */
.main-footer {
  background: var(--bg-alt);
  border-top: 1px solid var(--border-color);
  padding: 4rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 3rem;
}

.footer-col h4 {
  font-size: 1.1rem;
  margin-bottom: 1.5rem;
}

.footer-col p {
  color: var(--text-muted);
}

.footer-col ul li {
  margin-bottom: 0.75rem;
}

.footer-col ul a {
  color: var(--text-muted);
}

.footer-col ul a:hover {
  color: var(--primary-color);
}

.footer-bottom {
  text-align: center;
  border-top: 1px solid var(--border-color);
  padding-top: 2rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* Animations */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Accessibility settings support */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Responsive */
@media (max-width: 768px) {
  .hero-title { font-size: 3rem; }
  .split-layout { grid-template-columns: 1fr; gap: 2rem; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .nav-list { display: none; /* simple mobile nav approach for now */ }
}

@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; }
}