:root {
  --bg-dark: #0b0f19;
  --bg-card: #131b2e;
  --bg-card-hover: #1c2742;
  --accent-blue: #3b82f6;
  --accent-purple: #8b5cf6;
  --accent-green: #10b981;
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --border-color: #232d45;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

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

body {
  background-color: var(--bg-dark);
  color: var(--text-main);
  font-family: var(--font-sans);
  line-height: 1.6;
  scroll-behavior: smooth;
}

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

.section-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 80px 24px;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  text-align: center;
  margin-bottom: 48px;
}

/* Navbar */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  background: rgba(11, 15, 25, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 24px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1.3rem;
}

.logo-domain {
  color: var(--accent-blue);
}

.nav-links {
  display: flex;
  list-style: none;
  align-items: center;
  gap: 32px;
}

.nav-links a:hover {
  color: var(--accent-blue);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  font-size: 1.5rem;
  cursor: pointer;
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  border: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
  color: #fff;
}

.btn-primary:hover {
  opacity: 0.9;
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-main);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
}

.btn-outline {
  border: 1px solid var(--accent-blue);
  color: var(--accent-blue);
}

.btn-outline:hover {
  background: rgba(59, 130, 246, 0.1);
}

.btn-card {
  display: block;
  width: 100%;
  text-align: center;
  margin-top: 24px;
  background: var(--accent-blue);
  color: #fff;
}

.btn-offline-card {
  background: var(--accent-green);
}

.btn-block {
  width: 100%;
}

<!-- Hero -->
.hero {
  padding: 160px 24px 80px;
  text-align: center;
  background: radial-gradient(circle at top, rgba(59, 130, 246, 0.15) 0%, transparent 60%);
}

.hero-container {
  max-width: 900px;
  margin: 0 auto;
}

.badge {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: var(--accent-blue);
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: 3.2rem;
  line-height: 1.2;
  font-weight: 700;
  margin-bottom: 24px;
}

.gradient-text {
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtext {
  font-size: 1.2rem;
  color: var(--text-muted);
  margin-bottom: 36px;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 40px;
}

.trust-bar {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Variant Grid */
.variant-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}

.variant-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 40px;
  position: relative;
  transition: transform 0.2s, border-color 0.2s;
}

.variant-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-blue);
}

.variant-card.OnPrem:hover {
  border-color: var(--accent-green);
}

.card-tag {
  display: inline-block;
  padding: 4px 12px;
  background: rgba(59, 130, 246, 0.2);
  color: var(--accent-blue);
  border-radius: 6px;
  font-size: 0.75rem;
  font-weight: 700;
  margin-bottom: 16px;
  text-transform: uppercase;
}

.card-tag.tag-offline {
  background: rgba(16, 185, 129, 0.2);
  color: var(--accent-green);
}

.variant-card h3 {
  font-size: 1.75rem;
  margin-bottom: 12px;
}

.card-desc {
  color: var(--text-muted);
  margin-bottom: 24px;
}

.feature-list {
  list-style: none;
}

.feature-list li {
  margin-bottom: 12px;
  font-size: 0.95rem;
}

/* Architecture Toggle Section */
.arch-toggle {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 32px;
}

.toggle-btn {
  padding: 10px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
}

.toggle-btn.active {
  background: var(--accent-blue);
  color: #fff;
  border-color: var(--accent-blue);
}

.arch-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 32px;
}

.arch-diagram {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.arch-node-group {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.arch-node {
  background: var(--bg-card-hover);
  border: 1px solid var(--border-color);
  padding: 16px 24px;
  border-radius: 8px;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  text-align: center;
  min-width: 200px;
}

.arch-arrow {
  text-align: center;
  color: var(--text-muted);
  font-size: 1.2rem;
}

/* Demo Section */
.demo-widget {
  display: grid;
  grid-template-columns: 1fr 2fr;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  overflow: hidden;
}

.demo-sidebar {
  background: rgba(0, 0, 0, 0.2);
  padding: 24px;
  border-right: 1px solid var(--border-color);
}

.doc-badge {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  background: var(--bg-card-hover);
  padding: 8px;
  border-radius: 6px;
  margin: 12px 0;
  color: var(--accent-blue);
}

.doc-preview {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.demo-chat {
  display: flex;
  flex-direction: column;
  height: 400px;
}

.chat-header {
  padding: 16px 24px;
  background: var(--bg-card-hover);
  font-weight: 600;
  font-size: 0.9rem;
  border-bottom: 1px solid var(--border-color);
}

.chat-messages {
  flex: 1;
  padding: 24px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.message {
  padding: 12px 16px;
  border-radius: 8px;
  font-size: 0.9rem;
  max-width: 85%;
}

.message.system {
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  color: var(--accent-blue);
  align-self: center;
  font-size: 0.8rem;
}

.message.user {
  background: var(--accent-blue);
  color: #fff;
  align-self: flex-end;
}

.message.bot {
  background: var(--bg-card-hover);
  border: 1px solid var(--border-color);
  align-self: flex-start;
}

.citation {
  display: inline-block;
  margin-top: 8px;
  font-size: 0.75rem;
  color: var(--accent-green);
  font-family: var(--font-mono);
}

.chat-input-row {
  display: flex;
  padding: 16px;
  border-top: 1px solid var(--border-color);
  gap: 12px;
}

.chat-input-row input {
  flex: 1;
  background: var(--bg-dark);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  padding: 10px 16px;
  border-radius: 8px;
  outline: none;
}

.chat-input-row button {
  padding: 10px 20px;
  background: var(--accent-blue);
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
}

/* Security Grid */
.security-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.sec-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 32px;
  border-radius: 12px;
  text-align: center;
}

.sec-icon {
  font-size: 2rem;
  margin-bottom: 16px;
}

.sec-card h4 {
  font-size: 1.2rem;
  margin-bottom: 12px;
}

.sec-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Contact Form */
.contact-section {
  background: radial-gradient(circle at bottom, rgba(139, 92, 246, 0.1) 0%, transparent 60%);
}

.contact-card {
  max-width: 700px;
  margin: 0 auto;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 40px;
}

.contact-card h2 {
  font-size: 1.8rem;
  margin-bottom: 8px;
  text-align: center;
}

.contact-card > p {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 32px;
  font-size: 0.95rem;
}

.form-group-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 16px;
}

form input, form select, form textarea {
  width: 100%;
  background: var(--bg-dark);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  padding: 12px 16px;
  border-radius: 8px;
  font-family: inherit;
  font-size: 0.9rem;
  outline: none;
}

form textarea {
  margin-bottom: 24px;
  resize: vertical;
}

form input:focus, form select:focus, form textarea:focus {
  border-color: var(--accent-blue);
}

.form-status {
  margin-top: 16px;
  text-align: center;
  font-size: 0.9rem;
  color: var(--accent-green);
}

/* Footer */
footer {
  border-top: 1px solid var(--border-color);
  padding: 40px 24px;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-left p {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 4px;
}

.footer-right p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Responsive */
@media (max-width: 768px) {
  .variant-grid, .security-grid, .demo-widget, .form-group-row {
    grid-template-columns: 1fr;
  }

  .nav-links {
    display: none;
  }

  .mobile-menu-toggle {
    display: block;
  }

  .hero h1 {
    font-size: 2.2rem;
  }
}