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

:root {
  --color-bg: #fafafa;
  --color-surface: #ffffff;
  --color-border: #e5e5e5;
  --color-text: #1a1a1a;
  --color-text-secondary: #6b6b6b;
  --color-accent: #4A90D9;
  --color-accent-light: #e8f0fb;
  --color-badge-bg: #f0f0f0;
  --color-success: #2e7d32;
  --color-success-light: #e8f5e9;
  --color-warning: #ed6c02;
  --color-warning-light: #fff3e0;
  --radius: 12px;
  --radius-sm: 8px;
  --max-width: 1040px;
}

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

code {
  font-family: 'SF Mono', 'Fira Code', 'Fira Mono', Menlo, monospace;
  font-size: 0.875em;
  background: var(--color-badge-bg);
  padding: 2px 6px;
  border-radius: 4px;
}

/* --- Header --- */

header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-surface);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: box-shadow 0.2s;
}

header.scrolled {
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.06);
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 16px;
  flex-shrink: 0;
  text-decoration: none;
  color: inherit;
}

.nav-links {
  display: flex;
  gap: 28px;
}

.nav-links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color 0.15s;
}

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

.nav-links a.active {
  color: var(--color-text);
  position: relative;
}

.nav-links a.active::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -18px;
  height: 2px;
  background: var(--color-text);
  border-radius: 1px;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--color-text);
  padding: 4px;
}

/* --- Hero --- */

.hero {
  padding: 80px 24px 64px;
  text-align: center;
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
}

.hero-content {
  max-width: 640px;
  margin: 0 auto;
}

.badge {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  background: var(--color-accent-light);
  color: var(--color-accent);
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 20px;
}

.hero h1 {
  font-size: 44px;
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.15;
  margin-bottom: 20px;
  color: var(--color-text);
}

.subtitle {
  font-size: 17px;
  color: var(--color-text-secondary);
  max-width: 520px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  padding: 10px 24px;
  font-size: 14px;
  font-weight: 600;
  color: #fff;
  background: var(--color-text);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: background 0.15s;
}

.btn-primary:hover {
  background: #333;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  padding: 10px 24px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: border-color 0.15s, background 0.15s;
}

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

/* --- Sections --- */

.section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 64px 24px;
  width: 100%;
  border-top: 1px solid var(--color-border);
}

.section-header {
  margin-bottom: 40px;
}

.section-header h2 {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.section-header p {
  font-size: 16px;
  color: var(--color-text-secondary);
  max-width: 560px;
}

.section-cta {
  margin-top: 40px;
  text-align: center;
}

/* --- Prototype Cards --- */

.prototype-category {
  margin-bottom: 48px;
}

.prototype-category h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 4px;
}

.category-desc {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 20px;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 12px;
}

.proto-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  text-decoration: none;
  color: inherit;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.proto-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 2px 12px rgba(74, 144, 217, 0.08);
}

.proto-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.proto-card-title {
  font-size: 14px;
  font-weight: 600;
}

.copy-link-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border: none;
  background: none;
  color: var(--color-text-secondary);
  border-radius: 6px;
  cursor: pointer;
  flex-shrink: 0;
  opacity: 0;
  transition: opacity 0.15s, background 0.15s, color 0.15s;
}

.proto-card:hover .copy-link-btn {
  opacity: 1;
}

.copy-link-btn:hover {
  background: var(--color-accent-light);
  color: var(--color-accent);
}

/* Toast notification */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  background: var(--color-text);
  color: #fff;
  font-size: 14px;
  font-weight: 500;
  padding: 10px 24px;
  border-radius: var(--radius-sm);
  opacity: 0;
  transition: transform 0.25s, opacity 0.25s;
  z-index: 200;
  pointer-events: none;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.proto-card-desc {
  font-size: 13px;
  color: var(--color-text-secondary);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.proto-card-meta {
  font-size: 12px;
  color: var(--color-text-secondary);
  opacity: 0.7;
  margin-top: auto;
}

/* Version history toggle */

.version-history {
  margin-top: 12px;
}

.version-history summary {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-accent);
  cursor: pointer;
  padding: 4px 0;
}

.version-history summary:hover {
  text-decoration: underline;
}

.version-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 12px 0 0;
}

.version-list a {
  font-size: 13px;
  color: var(--color-text-secondary);
  text-decoration: none;
  padding: 4px 12px;
  background: var(--color-badge-bg);
  border-radius: 6px;
  transition: background 0.15s, color 0.15s;
}

.version-list a:hover {
  background: var(--color-accent-light);
  color: var(--color-accent);
}

/* --- Onboarding Grid --- */

.onboarding-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}

.info-card {
  padding: 24px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}

.info-card-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent-light);
  color: var(--color-accent);
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
}

.info-card h4 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
}

.info-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* --- Roadmap Timeline --- */

.roadmap-timeline {
  position: relative;
  padding-left: 32px;
  margin-bottom: 48px;
}

.roadmap-timeline::before {
  content: '';
  position: absolute;
  left: 9px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--color-border);
}

.roadmap-phase {
  position: relative;
  padding-bottom: 36px;
  display: flex;
  gap: 16px;
}

.roadmap-phase:last-child {
  padding-bottom: 0;
}

.phase-marker {
  position: absolute;
  left: -32px;
  top: 2px;
  z-index: 1;
}

.phase-dot {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  border: 2px solid var(--color-border);
  background: var(--color-surface);
}

.phase-dot.active {
  border-color: var(--color-accent);
  background: var(--color-accent);
  box-shadow: 0 0 0 4px var(--color-accent-light);
}

.phase-dot.pending {
  border-color: var(--color-border);
  background: var(--color-bg);
}

.phase-content {
  flex: 1;
}

.phase-content h4 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
}

.phase-status {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: 10px;
}

.phase-status.done {
  background: var(--color-success-light);
  color: var(--color-success);
}

.phase-status.active {
  background: var(--color-accent-light);
  color: var(--color-accent);
}

.phase-status.pending {
  background: var(--color-badge-bg);
  color: var(--color-text-secondary);
}

.phase-content ul {
  list-style: none;
  padding: 0;
}

.phase-content li {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 3px 0;
  padding-left: 16px;
  position: relative;
}

.phase-content li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 11px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--color-border);
}

.roadmap-done .phase-content li::before {
  background: var(--color-success);
}

.roadmap-active .phase-content li::before {
  background: var(--color-accent);
}

/* --- Metrics --- */

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.metric-card {
  text-align: center;
  padding: 24px 16px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}

.metric-value {
  display: block;
  font-size: 32px;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

.metric-label {
  display: block;
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-top: 4px;
}

/* --- Coming Soon Banner --- */

.coming-soon-banner {
  text-align: center;
  padding: 48px 24px 56px;
  margin-bottom: 40px;
  border-bottom: 1px solid var(--color-border);
}

.coming-soon-banner svg {
  margin-bottom: 24px;
}

.coming-soon-badge {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  background: #fff3e0;
  color: #ed6c02;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 16px;
}

.coming-soon-banner h2 {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.coming-soon-banner p {
  font-size: 16px;
  color: var(--color-text-secondary);
  max-width: 480px;
  margin: 0 auto;
  line-height: 1.6;
}

/* --- Home Grid --- */

.home-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}

.home-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 24px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  text-decoration: none;
  color: inherit;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.home-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 2px 12px rgba(74, 144, 217, 0.08);
}

.home-card-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent-light);
  color: var(--color-accent);
  border-radius: var(--radius-sm);
}

.home-card h3 {
  font-size: 16px;
  font-weight: 600;
}

.home-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

.home-card-link {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-accent);
  margin-top: auto;
}

/* --- Page Sections (sub-pages) --- */

.page-section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 48px 24px 64px;
  width: 100%;
}

.page-section .section-header {
  margin-bottom: 40px;
}

.page-section .section-header h1 {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.page-section .section-header p {
  font-size: 16px;
  color: var(--color-text-secondary);
  max-width: 560px;
}

/* --- Content Blocks (Onboarding detail sections) --- */

.content-block {
  margin-top: 48px;
  padding-top: 40px;
  border-top: 1px solid var(--color-border);
}

.content-block h2 {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 20px;
}

.content-block h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
  margin-top: 24px;
}

.content-block h3:first-of-type {
  margin-top: 0;
}

.content-block p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.6;
  margin-bottom: 12px;
}

.content-list {
  list-style: none;
  padding: 0;
  margin-bottom: 20px;
}

.content-list li {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding: 4px 0 4px 20px;
  position: relative;
}

.content-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 12px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-border);
}

.code-block {
  background: #f6f6f6;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  font-size: 13px;
  line-height: 1.8;
  margin-bottom: 16px;
  overflow-x: auto;
}

.code-block code {
  background: none;
  padding: 0;
  font-size: 13px;
}

.code-comment {
  color: var(--color-text-secondary);
  font-family: 'SF Mono', 'Fira Code', 'Fira Mono', Menlo, monospace;
  font-size: 13px;
}

.structure-block {
  white-space: pre;
  line-height: 1.6;
}

.content-note {
  font-size: 13px;
  color: var(--color-text-secondary);
  font-style: italic;
}

/* --- Resource Grid --- */

.resource-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 12px;
}

.resource-link {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 16px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: inherit;
  transition: border-color 0.15s;
}

.resource-link:hover {
  border-color: var(--color-accent);
}

.resource-link strong {
  font-size: 14px;
  font-weight: 600;
}

.resource-link span {
  font-size: 13px;
  color: var(--color-text-secondary);
}

/* --- Target Table (Roadmap) --- */

.target-table {
  overflow-x: auto;
}

.target-table table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.target-table th,
.target-table td {
  text-align: left;
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border);
}

.target-table th {
  font-weight: 600;
  font-size: 13px;
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: var(--color-badge-bg);
}

.target-table th:first-child {
  border-radius: var(--radius-sm) 0 0 0;
}

.target-table th:last-child {
  border-radius: 0 var(--radius-sm) 0 0;
}

.target-table td {
  color: var(--color-text-secondary);
}

.target-table td:first-child {
  color: var(--color-text);
  font-weight: 500;
}

.target-table tr:last-child td {
  border-bottom: none;
}

/* --- Footer --- */

footer {
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: var(--color-text-secondary);
  width: 100%;
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: 13px;
}

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

/* --- Responsive --- */

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    padding: 12px 24px 16px;
    gap: 12px;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a.active::after {
    display: none;
  }

  .nav-links a.active {
    color: var(--color-accent);
    font-weight: 600;
  }

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

  .hero {
    padding: 48px 24px 40px;
  }

  .hero h1 {
    font-size: 30px;
  }

  .subtitle {
    font-size: 15px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .section {
    padding: 48px 24px;
  }

  .section-header h2 {
    font-size: 24px;
  }

  .page-section .section-header h1 {
    font-size: 26px;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }

  .home-grid {
    grid-template-columns: 1fr;
  }

  .onboarding-grid {
    grid-template-columns: 1fr;
  }

  .resource-grid {
    grid-template-columns: 1fr;
  }

  .metrics-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .target-table {
    font-size: 13px;
  }

  .target-table th,
  .target-table td {
    padding: 8px 10px;
  }

  footer {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 26px;
  }

  .metrics-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
  }

  .metric-value {
    font-size: 26px;
  }
}