:root {
  --bg: #0b0f1a;
  --panel-bg: #121828;
  --panel-border: #253150;
  --text: #e8ecf7;
  --dim: #6b7794;
  --accent: #ea2328; /* Couchbase red */
  --accent-soft: #ff6b6f;
  --rosetta: #ffd166;
  --grid-line: #1a2236;

  --c-vec: #a855f7;
  --c-doc: #3b82f6;
  --c-sql: #14b8a6;
  --c-fts: #f97316;
  --c-cbas: #ec4899;
  --c-cache: #22c55e;
  --c-cb: var(--accent);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: radial-gradient(ellipse at top, #141b2e 0%, var(--bg) 60%);
  color: var(--text);
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  min-height: 100vh;
}

.app { max-width: 960px; margin: 0 auto; padding: 24px 16px 48px; }

.app-header { text-align: center; margin-bottom: 20px; }
.app-header h1 { font-size: 1.6rem; margin: 0 0 4px; letter-spacing: 0.02em; }
.brand { color: var(--accent); }
.dim { color: var(--dim); font-weight: 400; }
.tagline { color: var(--dim); margin: 0; font-size: 0.9rem; }

.layout {
  display: flex;
  gap: 20px;
  justify-content: center;
  flex-wrap: wrap;
}

.board-col { display: flex; flex-direction: column; align-items: center; gap: 14px; }

.board-wrap {
  position: relative;
  width: min(92vw, 300px);
}

#board {
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 2;
  border: 2px solid var(--panel-border);
  border-radius: 6px;
  background: #060810;
  box-shadow: 0 0 40px rgba(234, 35, 40, 0.08), inset 0 0 60px rgba(0,0,0,0.6);
  display: block;
  touch-action: none;
}

.json-col { width: 260px; }

.json-panel {
  padding: 12px 14px;
  height: 600px;
  display: flex;
  flex-direction: column;
  transition: box-shadow 0.3s ease, border-color 0.3s ease;
}
.json-panel.flash {
  border-color: var(--accent);
  box-shadow: 0 0 16px rgba(234, 35, 40, 0.35);
}

.json-badge {
  float: right;
  font-weight: 400;
  letter-spacing: normal;
  color: var(--dim);
  font-size: 0.65rem;
  background: #0c1120;
  border: 1px solid var(--panel-border);
  border-radius: 3px;
  padding: 1px 5px;
}

.json-view {
  margin: 0;
  flex: 1;
  overflow-y: auto;
  font-family: "SF Mono", "Cascadia Code", Consolas, monospace;
  font-size: 0.72rem;
  line-height: 1.5;
  white-space: pre;
  color: #c7cede;
}
.json-view::-webkit-scrollbar { width: 6px; }
.json-view::-webkit-scrollbar-thumb { background: var(--panel-border); border-radius: 3px; }

.json-view .jk { color: #7dd3fc; }
.json-view .js { color: #86efac; }
.json-view .jn { color: #fca5a5; }
.json-view .jb { color: #fbbf24; }
.json-view .jz { color: #94a3b8; }

.board-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: rgba(6, 8, 16, 0.82);
  border-radius: 6px;
  text-align: center;
  font-weight: 700;
  letter-spacing: 0.08em;
}
.board-overlay.hidden { display: none; }
#overlay-title { font-size: 1.5rem; color: var(--accent-soft); }
#overlay-sub { margin-top: 8px; font-size: 0.85rem; color: var(--dim); font-weight: 400; letter-spacing: normal; }

.side-col { width: 260px; display: flex; flex-direction: column; gap: 14px; }

.panel {
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 8px;
  padding: 12px 14px;
}

.panel-title {
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--dim);
  margin-bottom: 8px;
  font-weight: 700;
}

#next-panel { text-align: center; }
#next { display: block; margin: 0 auto; width: 120px; height: 120px; background: #060810; border-radius: 4px; }
.piece-name { margin-top: 6px; font-weight: 700; letter-spacing: 0.05em; font-size: 0.85rem; }

.stats-panel .stat {
  display: flex;
  justify-content: space-between;
  padding: 3px 0;
  font-size: 0.9rem;
}
.stat-label { color: var(--dim); }
.stat-value { font-weight: 700; font-variant-numeric: tabular-nums; }
.stat-line {
  display: flex;
  justify-content: space-between;
  gap: 6px;
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px solid var(--panel-border);
  font-size: 0.68rem;
  color: var(--dim);
}
.stat-line b { color: var(--text); }

.usage-panel { min-height: 118px; transition: opacity 0.25s ease; }
.fact-body { font-size: 0.82rem; line-height: 1.45; color: #c7cede; }

.controls-grid {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 4px 10px;
  font-size: 0.8rem;
  color: var(--dim);
}
.controls-grid span:nth-child(odd) { color: var(--text); font-weight: 600; }

.migrate-btn {
  width: 100%;
  margin-top: 12px;
  padding: 10px;
  border: 1px solid var(--accent);
  background: transparent;
  color: var(--accent-soft);
  border-radius: 6px;
  font-weight: 700;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}
.migrate-btn:hover { background: var(--accent); color: white; }
.migrate-btn:disabled {
  opacity: 0.35;
  cursor: default;
  border-color: var(--panel-border);
  color: var(--dim);
}
.migrate-btn:disabled:hover { background: transparent; }

.save-panel { text-align: center; padding: 8px 14px; }
.save-status { font-size: 0.72rem; color: var(--dim); }
.save-status.ok { color: var(--c-cache); }
.save-status.err { color: var(--accent-soft); }

.sync-panel { transition: box-shadow 0.3s ease, border-color 0.3s ease; }
.sync-panel.flash { border-color: var(--c-cache); box-shadow: 0 0 16px rgba(34, 197, 94, 0.35); }
.sync-conn {
  float: right;
  font-weight: 400;
  letter-spacing: normal;
  font-size: 0.65rem;
  color: var(--dim);
}
.sync-conn.live { color: var(--c-cache); }
.sync-conn.down { color: var(--accent-soft); }
.sync-body { font-size: 0.78rem; line-height: 1.4; color: #c7cede; }
.sync-body b { color: var(--text); }

/* Touch/on-screen controls: a game-console-style pad below the board.
   Hidden by default (desktop has a keyboard); shown on touch devices and
   on any narrow viewport, since a mouse-only narrow window still can't
   comfortably reach a sidebar button mid-game. */
.touch-controls {
  display: none;
  flex-direction: column;
  gap: 8px;
  width: min(92vw, 300px);
  user-select: none;
  -webkit-user-select: none;
}
.tc-row { display: flex; gap: 8px; }
.tc-btn {
  flex: 1;
  padding: 16px 0;
  font-size: 1.4rem;
  border-radius: 10px;
  border: 1px solid var(--panel-border);
  background: var(--panel-bg);
  color: var(--text);
  touch-action: manipulation;
  -webkit-touch-callout: none;
}
.tc-btn:active { background: var(--panel-border); }
.tc-btn.tc-wide { flex: 2; font-size: 1rem; font-weight: 700; letter-spacing: 0.05em; color: var(--accent-soft); }
.tc-row.tc-secondary { gap: 6px; }
.tc-btn-sm {
  flex: 1;
  padding: 10px 0;
  font-size: 0.78rem;
  border-radius: 8px;
  border: 1px solid var(--panel-border);
  background: transparent;
  color: var(--dim);
  touch-action: manipulation;
  -webkit-touch-callout: none;
}
.tc-btn-sm:active { background: var(--panel-border); color: var(--text); }

@media (hover: none), (max-width: 700px) {
  .touch-controls { display: flex; }
}

@media (max-width: 940px) {
  .layout { flex-direction: column; align-items: center; }
  .board-col { order: -1; }
  .side-col, .json-col { width: min(92vw, 300px); }
  .json-panel { height: 200px; }
}

@media (max-width: 380px) {
  .app-header h1 { font-size: 1.3rem; }
  .tc-btn { padding: 14px 0; font-size: 1.2rem; }
}