:root {
  --bg-color: #FAFAFA;
  --text-main: #1F2937;
  --primary: #2563EB;
  --primary-hover: #1D4ED8;
  --secondary: #E5E7EB;
  --lab-accent: #7C3AED;
  --lab-accent-hover: #6D28D9;
  --border: #E5E7EB;
}

* { box-sizing: border-box; }

body.hub-body,
body.lab-body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg-color);
  color: var(--text-main);
  margin: 0;
  min-height: 100vh;
  line-height: 1.55;
}

.site-header {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px 20px 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.site-header a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
}

.site-header a:hover { text-decoration: underline; }

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.hub-main,
.lab-main {
  max-width: 960px;
  margin: 0 auto;
  padding: 32px 20px 48px;
}

h1 { margin: 0 0 8px; color: #111827; font-size: 2rem; }
.subtitle { color: #4B5563; font-size: 1.15rem; margin: 0; }

.global-boundary,
.lab-boundary,
.wrapper-boundary {
  background: #FFFBEB;
  border: 1px solid #FCD34D;
  border-radius: 10px;
  color: #78350F;
  font-size: 0.92rem;
  line-height: 1.5;
  padding: 14px 16px;
}

.hub-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  margin-top: 32px;
}

.hub-card {
  background: #fff;
  border: 2px solid var(--border);
  border-radius: 16px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 28px;
}

.hub-card h2 { margin: 0; font-size: 1.35rem; }
.hub-card p { margin: 0; color: #4B5563; flex: 1; }

.hub-card--product { border-top: 4px solid var(--primary); }
.hub-card--lab { border-top: 4px solid var(--lab-accent); }

.primary-btn,
.secondary-btn,
.lab-btn {
  display: inline-block;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 600;
  padding: 12px 20px;
  text-align: center;
  text-decoration: none;
  transition: background 0.15s ease;
}

.primary-btn,
.hub-card--product .lab-btn {
  background: var(--primary);
  color: #fff;
}

.primary-btn:hover,
.hub-card--product .lab-btn:hover {
  background: var(--primary-hover);
  color: #fff;
}

.hub-card--lab .lab-btn {
  background: var(--lab-accent);
  color: #fff;
}

.hub-card--lab .lab-btn:hover {
  background: var(--lab-accent-hover);
  color: #fff;
}

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

.secondary-btn:hover { background: #D1D5DB; color: var(--text-main); }

.mt-1 { margin-top: 16px; }
.mt-2 { margin-top: 28px; }
.text-muted { color: #6B7280; font-size: 0.95rem; }

.site-footer {
  border-top: 1px solid var(--border);
  color: #6B7280;
  font-size: 0.9rem;
  margin-top: 40px;
  max-width: 960px;
  margin-left: auto;
  margin-right: auto;
  padding: 24px 20px 40px;
}

.site-footer a { color: var(--primary); }

.lab-strip {
  background: #F5F3FF;
  border: 1px solid #DDD6FE;
  border-radius: 10px;
  margin-top: 20px;
  padding: 14px 16px;
  text-align: center;
}

.lab-strip a {
  color: var(--lab-accent);
  font-weight: 600;
  text-decoration: none;
}

.lab-strip a:hover { text-decoration: underline; }