:root {
  --bg-primary: #222831;
  --bg-deeper: #1a1f27;
  --bg-surface: #2c3440;
  --accent: #4166F5;
  --text-primary: #f0f0f0;
  --text-secondary: #8a94a6;
  --border-color: #3a4250;
  
  --transition-fast: 150ms ease;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition-fast), text-shadow var(--transition-fast);
}

a:hover {
  text-shadow: 0 0 8px rgba(65, 102, 245, 0.4);
}

ul {
  list-style: none;
}

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

/* Header & Nav */
.site-header {
  position: sticky;
  top: 0;
  width: 100%;
  z-index: 100;
  background-color: rgba(26, 31, 39, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border-color);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

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

.nav-links {
  display: flex;
  gap: 2rem;
  align-items: center;
}

.nav-links a {
  color: var(--text-secondary);
  font-weight: 500;
  padding: 0.5rem 0;
  position: relative;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-primary);
  text-shadow: none;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--transition-fast);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  transform: scaleX(1);
  transform-origin: left;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.hamburger {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--text-primary);
  position: relative;
  transition: background-color var(--transition-fast);
}

.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--text-primary);
  transition: transform var(--transition-fast);
}

.hamburger::before {
  top: -6px;
}

.hamburger::after {
  bottom: -6px;
}

/* Layout */
main {
  flex: 1;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 4rem 1.5rem;
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 6rem 1.5rem;
  background-color: var(--bg-deeper);
  border-bottom: 1px solid var(--border-color);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, rgba(65, 102, 245, 0.15) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-title {
  font-size: 4rem;
  font-weight: 800;
  letter-spacing: -1px;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 2.5rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  font-weight: 600;
  border-radius: 4px;
  cursor: pointer;
  border: none;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), background-color var(--transition-fast);
  text-align: center;
}

.btn-primary {
  background-color: var(--accent);
  color: #fff;
  text-shadow: none;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(65, 102, 245, 0.3);
  text-shadow: none;
  color: #fff;
}

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

.btn-secondary:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  color: var(--text-primary);
}

.btn:disabled,
.btn.disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
  background-color: var(--bg-surface);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
}

/* Section Titles */
.section-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 2rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 1rem;
}

.section-subtitle {
  color: var(--text-secondary);
  margin-bottom: 2.5rem;
  font-size: 1.1rem;
}

/* Cards Grid */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 2rem;
}

.card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
  overflow: hidden;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), border-color var(--transition-fast);
  display: flex;
  flex-direction: column;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2), 0 0 12px rgba(65, 102, 245, 0.15);
  border-color: var(--border-color);
  border-left-color: var(--accent);
}

.card-content {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.card-header {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1rem;
}

.card-icon {
  width: 64px;
  height: 64px;
  border-radius: 12px;
  background-color: var(--bg-deeper);
  object-fit: cover;
  border: 1px solid var(--border-color);
}

.card-icon-link {
  display: inline-flex;
  border-radius: 12px;
  flex-shrink: 0;
}

.card-icon-link:hover {
  text-shadow: none;
}

.card-title-link {
  color: var(--text-primary);
}

.card-title-link:hover {
  color: var(--accent);
}

.card-title-group {
  flex: 1;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.badge {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  border-radius: 99px;
  background-color: var(--bg-deeper);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
}

.badge.accent {
  color: var(--accent);
  border-color: rgba(65, 102, 245, 0.3);
  background-color: rgba(65, 102, 245, 0.05);
}

.card-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
  flex: 1;
}

.card-footer {
  margin-top: auto;
}

.card-link {
  display: inline-flex;
  align-items: center;
  font-weight: 600;
  font-size: 0.9rem;
  gap: 0.5rem;
}

.card-link::after {
  content: '→';
  transition: transform var(--transition-fast);
}

.card:hover .card-link::after {
  transform: translateX(4px);
}

/* Detail Page */
.detail-header {
  padding: 4rem 1.5rem;
  background-color: var(--bg-deeper);
  border-bottom: 1px solid var(--border-color);
}

.detail-header-content {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  gap: 2rem;
  align-items: center;
}

.detail-icon {
  width: 128px;
  height: 128px;
  border-radius: 20px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.3);
  border: 1px solid var(--border-color);
}

.detail-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 1rem;
}

.detail-main {
  max-width: 900px;
  margin: 0 auto;
  padding: 4rem 1.5rem;
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 3rem;
}

.detail-body h2 {
  font-size: 1.5rem;
  margin: 2rem 0 1rem;
  color: var(--text-primary);
}

.detail-body p {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  font-size: 1.05rem;
}

.detail-short-description {
  margin-bottom: 1rem;
}

.expandable-description {
  margin-bottom: 2rem;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  overflow: hidden;
}

.expandable-description summary {
  list-style: none;
  cursor: pointer;
  padding: 0.9rem 1rem;
  color: var(--accent);
  font-weight: 600;
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.expandable-description summary::-webkit-details-marker {
  display: none;
}

.expandable-description summary:hover {
  background-color: rgba(65, 102, 245, 0.06);
}

.expandable-description[open] summary {
  border-bottom: 1px solid var(--border-color);
}

.expandable-description summary::after {
  content: '+';
  float: right;
}

.expandable-description[open] summary::after {
  content: '−';
}

.expandable-description-content {
  padding: 1rem;
}

.expandable-description-content p {
  margin-bottom: 1rem;
  line-height: 1.75;
}

.expandable-description-content strong {
  color: var(--text-primary);
}

.storefront-section {
  margin: 1.5rem 0;
  padding: 1rem 1rem 1rem 1.1rem;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.02), rgba(255, 255, 255, 0));
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-left: 2px solid rgba(65, 102, 245, 0.35);
  border-radius: 8px;
}

.storefront-section h3 {
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  font-size: 1rem;
  letter-spacing: 0.01em;
}

.storefront-section p {
  margin-bottom: 0.75rem;
}

.storefront-list {
  list-style: none;
  display: grid;
  gap: 0.75rem;
}

.storefront-list li {
  position: relative;
  padding-left: 1rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.storefront-list li::before {
  content: '';
  position: absolute;
  top: 0.72rem;
  left: 0;
  width: 0.38rem;
  height: 0.38rem;
  border-radius: 999px;
  background-color: var(--accent);
  box-shadow: 0 0 8px rgba(65, 102, 245, 0.35);
}

.expandable-description-content p:last-child {
  margin-bottom: 0;
}

.detail-sidebar {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  height: fit-content;
}

.info-item {
  margin-bottom: 1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-color);
}

.info-item:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: none;
}

.info-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.info-value {
  font-weight: 500;
  color: var(--text-primary);
}

.sidebar-actions {
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.sidebar-actions .btn {
  width: 100%;
}

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

.changelog-list li {
  padding: 1rem 0;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-secondary);
}

.changelog-list li strong {
  color: var(--text-primary);
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: 4rem 2rem;
  background-color: var(--bg-surface);
  border: 1px dashed var(--border-color);
  border-radius: 8px;
  color: var(--text-secondary);
}

/* Reading Layout */
.reading-layout {
  max-width: 800px;
  margin: 0 auto;
}

.reading-layout h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.reading-layout .meta {
  color: var(--text-secondary);
  margin-bottom: 2rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border-color);
}

.reading-layout p {
  margin-bottom: 1.5rem;
  color: var(--text-secondary);
  font-size: 1.1rem;
}

/* Footer */
.site-footer {
  background-color: var(--bg-deeper);
  border-top: 1px solid var(--border-color);
  padding: 3rem 1.5rem;
  text-align: center;
  margin-top: auto;
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  color: var(--text-secondary);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

/* Responsive */
@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background-color: var(--bg-deeper);
    flex-direction: column;
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
  }
  
  .nav-links.active {
    display: flex;
  }
  
  .mobile-menu-btn {
    display: block;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-actions {
    flex-direction: column;
  }
  
  .detail-header-content {
    flex-direction: column;
    text-align: center;
  }
  
  .detail-main {
    grid-template-columns: 1fr;
  }
}