:root {
  --bg: #0f1419;
  --panel: #1a2332;
  --border: #2d3a4f;
  --text: #e8eef7;
  --muted: #8fa3bf;
  --accent: #3d8bfd;
  --ok: #3ecf8e;
  --warn: #f0b429;
  --danger: #ff6b6b;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.hidden { display: none !important; }
.muted { color: var(--muted); font-size: 0.9rem; }
.error { color: var(--danger); }
.ok { color: var(--ok); }

.login-panel {
  max-width: 400px;
  margin: 10vh auto;
  padding: 2rem;
}

.panel, .card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
}

label {
  display: block;
  margin: 1rem 0 0.5rem;
  font-size: 0.9rem;
}

input, select, textarea {
  width: 100%;
  padding: 0.65rem 0.75rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: #0c1118;
  color: var(--text);
}

button {
  margin-top: 1rem;
  padding: 0.65rem 1rem;
  border: none;
  border-radius: 8px;
  background: var(--accent);
  color: white;
  cursor: pointer;
}

button.secondary { background: #334155; }
button.danger { background: var(--danger); }

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border);
}

.tabs {
  display: flex;
  gap: 0.5rem;
  padding: 1rem 1.5rem 0;
  flex-wrap: wrap;
}

.tabs button {
  margin: 0;
  background: transparent;
  border: 1px solid var(--border);
}

.tabs button.active {
  background: var(--accent);
  border-color: var(--accent);
}

main { padding: 1.5rem; }

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

.card { padding: 1rem; }
.card h3 { margin: 0 0 0.5rem; font-size: 1rem; }
.card .value { font-size: 1.8rem; font-weight: 700; }

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

th, td {
  border-bottom: 1px solid var(--border);
  padding: 0.65rem;
  text-align: left;
  vertical-align: top;
}

.actions { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.actions button { margin: 0; font-size: 0.85rem; }

.form-card { padding: 1rem; margin-bottom: 1rem; }

pre {
  background: #0c1118;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.75rem;
  overflow: auto;
  font-size: 0.8rem;
}

.badge {
  display: inline-block;
  padding: 0.15rem 0.5rem;
  border-radius: 999px;
  font-size: 0.75rem;
  background: #334155;
}

.badge.on { background: #14532d; color: #86efac; }
.badge.off { background: #450a0a; color: #fca5a5; }
.badge.warn { background: #422006; color: #fcd34d; }

.foldable-text {
  max-width: 280px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.heatmap { margin-top: 0.5rem; }
.heat-row {
  display: grid;
  grid-template-columns: 120px 1fr 48px;
  gap: 0.75rem;
  align-items: center;
  margin-bottom: 0.5rem;
}
.heat-label { font-size: 0.85rem; color: var(--muted); }
.heat-bar {
  height: 10px;
  background: #1e293b;
  border-radius: 999px;
  overflow: hidden;
}
.heat-fill {
  height: 100%;
  background: linear-gradient(90deg, #2563eb, #3d8bfd);
  border-radius: 999px;
}
.heat-count { font-size: 0.85rem; text-align: right; }

details summary {
  cursor: pointer;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.playground-layout {
  display: grid;
  grid-template-columns: minmax(280px, 360px) 1fr;
  gap: 1.25rem;
  align-items: start;
}

@media (max-width: 900px) {
  .playground-layout { grid-template-columns: 1fr; }
}

.playground-panel { padding: 1rem; }

.pg-subtabs {
  display: flex;
  gap: 0.35rem;
  flex-wrap: wrap;
  margin-bottom: 0.75rem;
}

.pg-subtabs button {
  margin: 0;
  font-size: 0.8rem;
  padding: 0.4rem 0.65rem;
  background: #1e293b;
}

.pg-subtabs button.active {
  background: var(--accent);
}

.pg-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
  font-size: 0.85rem;
  margin-bottom: 0.75rem;
  color: var(--muted);
}

.pg-meta strong { color: var(--text); }

.checkbox-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.75rem;
  font-size: 0.85rem;
}

.checkbox-row input { width: auto; }

.ai-nav {
  border-top: 1px solid var(--border);
  padding-top: 0.75rem;
  align-items: center;
}

.ai-nav-label {
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  margin-right: 0.25rem;
}

.ai-nav .ai-link {
  background: #1e293b;
  font-size: 0.85rem;
}

.ai-nav .ai-link.active {
  background: #2563eb;
  border-color: #2563eb;
}

.rule-header {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1rem;
  margin-bottom: 1rem;
}

.rule-meta-card {
  padding: 0.85rem 1rem;
}

.rule-meta-card .label { color: var(--muted); font-size: 0.75rem; }
.rule-meta-card .value { font-size: 1.1rem; font-weight: 600; margin-top: 0.25rem; }

.rule-editor-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

@media (max-width: 960px) {
  .rule-editor-layout { grid-template-columns: 1fr; }
}

.rule-editor textarea {
  min-height: 420px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.85rem;
  line-height: 1.5;
}

.rule-preview {
  min-height: 420px;
  padding: 1rem;
  background: #0c1118;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: auto;
}

.rule-preview h1, .rule-preview h2, .rule-preview h3 { margin-top: 1rem; }
.rule-preview table { width: 100%; border-collapse: collapse; margin: 0.75rem 0; }
.rule-preview th, .rule-preview td { border: 1px solid var(--border); padding: 0.4rem 0.6rem; }
.rule-preview pre { background: #111827; }
.rule-preview ul.task-list { list-style: none; padding-left: 0; }
.rule-preview .task-list-item input { width: auto; margin-right: 0.5rem; }

.rule-actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

.rule-actions button { margin: 0; }

.diff-panel {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.diff-col pre { max-height: 360px; }

.diff-line-add { color: #86efac; }
.diff-line-del { color: #fca5a5; }