:root {
  --bg: #0f172a;
  --bg-alt: #1e293b;
  --surface: #ffffff;
  --surface-muted: #f1f5f9;
  --border: #e2e8f0;
  --text: #0f172a;
  --text-muted: #475569;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --accent: #14b8a6;
  --danger: #dc2626;
  --radius: 10px;
  --radius-sm: 6px;
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.08);
  --shadow: 0 10px 25px -12px rgba(15, 23, 42, 0.25);
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; }

body {
  font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--surface-muted);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}
.site-header .brand {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text);
}
.site-header nav { display: flex; gap: 1rem; align-items: center; }

.site-footer {
  text-align: center;
  padding: 2rem;
  color: var(--text-muted);
  font-size: 0.875rem;
}

main { max-width: 1100px; margin: 0 auto; padding: 2rem 1.5rem 4rem; }

.btn {
  display: inline-block;
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius-sm);
  font-weight: 500;
  font-size: 0.95rem;
  cursor: pointer;
  border: 1px solid transparent;
  transition: background 0.12s ease, border-color 0.12s ease, color 0.12s ease;
}
.btn-primary { background: var(--primary); color: white; }
.btn-primary:hover { background: var(--primary-hover); text-decoration: none; }
.btn-ghost { background: transparent; color: var(--text); border-color: var(--border); }
.btn-ghost:hover { background: var(--surface-muted); text-decoration: none; }
.btn-danger { background: var(--danger); color: white; }
.btn-lg { padding: 0.85rem 1.5rem; font-size: 1rem; }

.hero {
  text-align: center;
  padding: 4rem 1rem 3rem;
}
.hero h1 { font-size: 2.5rem; margin: 0 0 1rem; }
.hero .lead { font-size: 1.125rem; color: var(--text-muted); max-width: 640px; margin: 0 auto 2rem; }
.hero-cta { display: flex; gap: 0.75rem; justify-content: center; flex-wrap: wrap; }

.features { margin: 3rem 0; }
.features h2 { text-align: center; font-size: 1.75rem; margin-bottom: 2rem; }
.feature-grid {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 1.25rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}
.feature-grid li {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
}
.feature-grid h3 { margin: 0 0 0.5rem; font-size: 1.1rem; }
.feature-grid p { margin: 0; color: var(--text-muted); }

.cta {
  margin-top: 4rem;
  padding: 3rem 1rem;
  text-align: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.cta h2 { margin: 0 0 0.75rem; font-size: 1.75rem; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.form-row { margin-bottom: 1rem; }
.form-row label { display: block; margin-bottom: 0.35rem; font-weight: 500; font-size: 0.9rem; }
.form-row input, .form-row textarea, .form-row select {
  width: 100%;
  padding: 0.6rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-family: inherit;
}
.form-row input:focus, .form-row textarea:focus, .form-row select:focus {
  outline: 2px solid var(--primary);
  outline-offset: 0;
  border-color: var(--primary);
}
.alert { padding: 0.75rem 1rem; border-radius: var(--radius-sm); margin-bottom: 1rem; }
.alert-error { background: #fef2f2; color: var(--danger); border: 1px solid #fecaca; }
.alert-success { background: #ecfdf5; color: #047857; border: 1px solid #a7f3d0; }
.alert-warning { background: #fffbeb; color: #b45309; border: 1px solid #fde68a; }

.dashboard-layout { display: grid; grid-template-columns: 240px 1fr; gap: 2rem; align-items: start; }
.dashboard-layout aside {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
  position: sticky;
  top: 1rem;
}
.dashboard-layout aside nav { display: flex; flex-direction: column; gap: 0.25rem; }
.dashboard-layout aside nav a {
  display: block;
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  color: var(--text);
}
.dashboard-layout aside nav a.active { background: var(--surface-muted); font-weight: 600; }
.dashboard-layout aside nav a:hover { background: var(--surface-muted); text-decoration: none; }

.instance-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}
.instance-card .meta { color: var(--text-muted); font-size: 0.875rem; margin: 0.25rem 0; }
.instance-card .embed {
  background: var(--surface-muted);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.5rem 0.75rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.8rem;
  overflow-x: auto;
  white-space: nowrap;
}

.badge {
  display: inline-block;
  padding: 0.2rem 0.55rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.badge-active { background: #ecfdf5; color: #047857; }
.badge-pending { background: #fffbeb; color: #b45309; }
.badge-error { background: #fef2f2; color: var(--danger); }

@media (max-width: 720px) {
  .dashboard-layout { grid-template-columns: 1fr; }
  .dashboard-layout aside { position: static; }
  .hero h1 { font-size: 1.75rem; }
}