:root {
  --bg-dark: #090b10;
  --bg-primary: #0f121b;
  --bg-secondary: #151a27;
  --bg-card: #1b2133;
  --bg-card-hover: #222940;
  --accent: #ff2b4f;
  --accent-hover: #ff4767;
  --accent-glow: rgba(255, 43, 79, 0.4);
  --accent-soft: rgba(255, 43, 79, 0.12);
  --text-main: #f8fafc;
  --text-soft: #cbd5e1;
  --text-muted: #94a3b8;
  --border: rgba(255, 255, 255, 0.08);
  --border-active: rgba(255, 43, 79, 0.5);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition);
}

/* Background Atmosphere Glows */
.bg-glow-top {
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 900px;
  height: 500px;
  background: radial-gradient(circle at center, rgba(255, 43, 79, 0.15) 0%, rgba(15, 18, 27, 0) 70%);
  filter: blur(80px);
  pointer-events: none;
  z-index: 0;
}

/* Navbar */
.navbar {
  position: sticky;
  top: 0;
  background: rgba(15, 18, 27, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0.9rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
}

.brand-logo {
  width: 36px;
  height: 36px;
  border-radius: 8px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.8rem;
  list-style: none;
}

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

.nav-links a:hover, .nav-links a.active {
  color: var(--text-main);
}

.nav-cta-group {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.btn-github {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0.55rem 1rem;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  color: var(--text-soft);
  font-size: 0.9rem;
  font-weight: 500;
}

.btn-github:hover {
  background: var(--bg-card);
  border-color: var(--border-active);
  color: var(--text-main);
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0.65rem 1.4rem;
  border-radius: var(--radius-sm);
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  font-size: 0.95rem;
  box-shadow: 0 4px 18px var(--accent-glow);
  cursor: pointer;
  border: none;
  transition: var(--transition);
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 24px var(--accent-glow);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0.65rem 1.4rem;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  color: var(--text-main);
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid var(--border);
  cursor: pointer;
  transition: var(--transition);
}

.btn-secondary:hover {
  background: var(--bg-card);
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

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

/* Hero Section */
.hero {
  position: relative;
  max-width: 1200px;
  margin: 0 auto;
  padding: 5rem 1.5rem 4rem;
  text-align: center;
  z-index: 10;
}

.badge-wrapper {
  margin-bottom: 1.5rem;
}

.version-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 0.35rem 0.9rem;
  background: var(--accent-soft);
  border: 1px solid rgba(255, 43, 79, 0.3);
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 600;
  color: #ff6685;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--accent);
}

.hero h1 {
  font-size: clamp(2.4rem, 5vw, 3.8rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 1.25rem;
  color: #ffffff;
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.3rem);
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 2.5rem;
  font-weight: 400;
}

.hero-buttons {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 3.5rem;
}

.platform-info {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  color: var(--text-muted);
  font-size: 0.88rem;
  flex-wrap: wrap;
}

.platform-pill {
  display: flex;
  align-items: center;
  gap: 6px;
  background: rgba(255, 255, 255, 0.03);
  padding: 0.3rem 0.75rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}

/* App Window Preview Mockup */
.preview-window {
  max-width: 1000px;
  margin: 3.5rem auto 0;
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: 0 25px 60px rgba(0, 0, 0, 0.6), 0 0 40px rgba(255, 43, 79, 0.1);
  overflow: hidden;
  text-align: left;
}

.window-header {
  background: var(--bg-secondary);
  padding: 0.85rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border);
}

.window-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.window-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.dot-red { background: #ef4444; }
.dot-yellow { background: #f59e0b; }
.dot-green { background: #10b981; }

.window-title {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

.window-body {
  padding: 2.5rem;
  background: linear-gradient(180deg, rgba(21, 26, 39, 0.5) 0%, rgba(15, 18, 27, 0.9) 100%);
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 2rem;
  min-height: 400px;
}

.mock-sidebar {
  border-right: 1px solid var(--border);
  padding-right: 1.5rem;
}

.mock-side-item {
  padding: 0.65rem 0.9rem;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 0.35rem;
  display: flex;
  align-items: center;
  gap: 10px;
}

.mock-side-item.active {
  background: var(--accent-soft);
  color: #fff;
  font-weight: 600;
  border-left: 3px solid var(--accent);
}

.mock-hero-content {
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.mock-badge {
  color: var(--accent);
  font-weight: 700;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}

.mock-title {
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  color: #fff;
}

.mock-tags {
  display: flex;
  gap: 8px;
  margin-bottom: 1.5rem;
}

.mock-tag {
  background: var(--bg-card);
  padding: 0.25rem 0.6rem;
  border-radius: 4px;
  font-size: 0.78rem;
  color: var(--text-soft);
  border: 1px solid var(--border);
}

.mock-play-btn {
  align-self: flex-start;
  padding: 0.85rem 2rem;
  font-size: 1.1rem;
}

/* Sections */
.section {
  max-width: 1200px;
  margin: 0 auto;
  padding: 5rem 1.5rem;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 3.5rem;
}

.section-tag {
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.5rem;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
}

.section-desc {
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.75rem;
}

.feature-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 2rem;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.feature-card:hover {
  background: var(--bg-card);
  border-color: rgba(255, 43, 79, 0.35);
  transform: translateY(-4px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
}

.feature-icon-box {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-sm);
  background: var(--accent-soft);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  margin-bottom: 1.25rem;
}

.feature-card h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.65rem;
  color: #fff;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* Server Card Banner */
.server-banner {
  background: linear-gradient(135deg, rgba(27, 33, 51, 0.9) 0%, rgba(21, 26, 39, 0.95) 100%);
  border: 1px solid var(--border-active);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  flex-wrap: wrap;
  margin-top: 4rem;
  box-shadow: 0 10px 40px rgba(255, 43, 79, 0.08);
}

.server-info h3 {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 0.4rem;
  color: #fff;
}

.server-ip-box {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--bg-dark);
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  font-family: monospace;
  font-size: 1.1rem;
  color: #fff;
}

.btn-copy {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-soft);
  padding: 0.45rem 0.85rem;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
  transition: var(--transition);
}

.btn-copy:hover {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

/* Documentation Tabs */
.docs-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 2.5rem;
  margin-top: 2rem;
}

.docs-nav {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.docs-nav-btn {
  text-align: left;
  padding: 0.85rem 1.1rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.docs-nav-btn:hover {
  background: var(--bg-card);
  color: var(--text-main);
}

.docs-nav-btn.active {
  background: var(--accent-soft);
  color: #fff;
  border-color: var(--accent);
}

.docs-content-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 2.5rem;
  min-height: 480px;
}

.doc-article {
  display: none;
}

.doc-article.active {
  display: block;
}

.doc-article h2 {
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 1rem;
  color: #fff;
}

.doc-article p, .doc-article ul {
  color: var(--text-soft);
  font-size: 1rem;
  margin-bottom: 1.25rem;
  line-height: 1.7;
}

.doc-article ul {
  padding-left: 1.5rem;
}

.doc-article code {
  background: var(--bg-dark);
  padding: 0.2rem 0.45rem;
  border-radius: 4px;
  font-family: monospace;
  color: #ff859d;
  font-size: 0.9em;
  border: 1px solid var(--border);
}

/* Footer */
.footer {
  background: var(--bg-primary);
  border-top: 1px solid var(--border);
  padding: 4rem 1.5rem 2.5rem;
  margin-top: 5rem;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 0.75rem;
  max-width: 340px;
}

.footer-col h4 {
  color: #fff;
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 1.1rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

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

.footer-col li {
  margin-bottom: 0.6rem;
}

.footer-col a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-col a:hover {
  color: var(--text-main);
}

.footer-bottom {
  max-width: 1200px;
  margin: 0 auto;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--text-muted);
  font-size: 0.85rem;
  flex-wrap: wrap;
  gap: 1rem;
}

/* YouTube Section */
.youtube-section-container {
  max-width: 1000px;
  margin: 0 auto;
}

.youtube-empty-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2rem;
  display: flex;
  align-items: center;
  gap: 2rem;
  box-shadow: 0 12px 36px rgba(0, 0, 0, 0.35);
  transition: var(--transition);
}

.youtube-empty-card:hover {
  border-color: var(--border-active);
  transform: translateY(-2px);
}

.youtube-empty-icon {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: var(--accent-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  border: 1px solid rgba(255, 43, 79, 0.25);
}

.youtube-empty-content {
  flex: 1;
}

.youtube-empty-content h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.youtube-empty-content p {
  color: var(--text-soft);
  font-size: 0.95rem;
  line-height: 1.6;
}

.youtube-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.youtube-video-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-col: column;
  transition: var(--transition);
}

.youtube-video-card:hover {
  border-color: var(--border-active);
  transform: translateY(-4px);
}

.youtube-video-thumb {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: #000;
}

.youtube-video-info {
  padding: 1rem;
}

.youtube-video-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 0.5rem;
  line-height: 1.4;
}

.youtube-video-date {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* Responsive */
@media (max-width: 900px) {
  .nav-links, .nav-cta-group {
    display: none;
  }
  .mobile-toggle {
    display: block;
  }
  .window-body {
    grid-template-columns: 1fr;
  }
  .mock-sidebar {
    display: none;
  }
  .docs-layout {
    grid-template-columns: 1fr;
  }
  .footer-container {
    grid-template-columns: 1fr;
  }
  .youtube-empty-card {
    flex-direction: column;
    text-align: center;
    gap: 1.25rem;
  }
  .youtube-empty-icon {
    margin: 0 auto;
  }
}