:root {
  --bg: #0b0e14;
  --panel: #121826;
  --panel-edge: #1e2740;
  --text: #dbe4f5;
  --text-dim: #7787a3;
  --cyan: #22d3ee;
  --magenta: #f43f5e;
  --amber: #fbbf24;
  --green: #34d399;
  --mono: "SF Mono", ui-monospace, "Cascadia Mono", Menlo, Consolas, monospace;
}

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

body {
  background:
    radial-gradient(1200px 500px at 70% -10%, rgba(34, 211, 238, 0.07), transparent 60%),
    radial-gradient(900px 400px at 10% 110%, rgba(244, 63, 94, 0.06), transparent 60%),
    var(--bg);
  color: var(--text);
  font-family: -apple-system, "Segoe UI", Inter, Roboto, sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ---------- header ---------- */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 22px;
  border-bottom: 1px solid var(--panel-edge);
}

.brand { display: flex; align-items: baseline; gap: 10px; }
.brand-mark {
  width: 10px; height: 10px; border-radius: 2px;
  background: linear-gradient(135deg, var(--cyan), var(--magenta));
  align-self: center;
  box-shadow: 0 0 12px rgba(34, 211, 238, 0.6);
}
.brand h1 { font-size: 18px; letter-spacing: 3px; font-weight: 700; }
.brand-sub { font-size: 10px; letter-spacing: 2px; color: var(--text-dim); }

.transport { display: flex; align-items: center; gap: 14px; }

.meter {
  width: 120px; height: 8px; border-radius: 4px;
  background: #0a0f1a;
  border: 1px solid var(--panel-edge);
  overflow: hidden;
}
.meter-fill {
  height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--green) 0 60%, var(--amber) 60% 85%, var(--magenta) 85%);
  transition: width 60ms linear;
}

/* ---------- layout ---------- */
.grid {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  padding: 18px 22px;
  max-width: 1180px;
  width: 100%;
  margin: 0 auto;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--panel-edge);
  border-radius: 14px;
  padding: 18px 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.panel-wide { grid-column: 1 / -1; }

.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.panel-head h2 { font-size: 12px; letter-spacing: 2.5px; color: var(--text-dim); font-weight: 600; }

.chip {
  font-family: var(--mono);
  font-size: 10px;
  color: var(--text-dim);
  border: 1px solid var(--panel-edge);
  border-radius: 20px;
  padding: 3px 10px;
}

/* ---------- BPM readouts ---------- */
.bpm-readout { display: flex; align-items: baseline; gap: 10px; justify-content: center; }
.bpm-value {
  font-family: var(--mono);
  font-size: 76px;
  font-weight: 700;
  line-height: 1;
  color: var(--text);
  font-variant-numeric: tabular-nums;
  text-shadow: 0 0 30px rgba(34, 211, 238, 0.25);
}
.bpm-value.accent { color: var(--cyan); }
.bpm-unit { font-family: var(--mono); font-size: 16px; color: var(--text-dim); letter-spacing: 2px; }

.sub-readout {
  text-align: center;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--text-dim);
  min-height: 16px;
}

/* ---------- tap pad ---------- */
.tap-pad {
  height: 130px;
  border-radius: 12px;
  border: 1px solid var(--panel-edge);
  background: linear-gradient(180deg, #182136, #10182a);
  color: var(--text);
  font-size: 26px;
  font-weight: 700;
  letter-spacing: 6px;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: transform 40ms ease, box-shadow 40ms ease, border-color 40ms ease;
  user-select: none;
  -webkit-user-select: none;
}
.tap-pad small { font-size: 10px; letter-spacing: 3px; color: var(--text-dim); font-weight: 400; }
.tap-pad:hover { border-color: var(--cyan); }
.tap-pad.hit {
  transform: scale(0.985);
  border-color: var(--cyan);
  box-shadow: 0 0 30px rgba(34, 211, 238, 0.35), inset 0 0 24px rgba(34, 211, 238, 0.12);
}

/* ---------- buttons ---------- */
.btn-row { display: flex; gap: 8px; }
.btn {
  flex: 1;
  padding: 9px 12px;
  border-radius: 8px;
  border: 1px solid var(--panel-edge);
  background: #182136;
  color: var(--text);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 1px;
  cursor: pointer;
  transition: border-color 80ms, background 80ms;
}
.btn:hover { border-color: var(--cyan); }
.btn.active { border-color: var(--cyan); color: var(--cyan); }
.btn-warn:hover { border-color: var(--magenta); color: var(--magenta); }
.btn-primary {
  flex: none;
  background: linear-gradient(135deg, rgba(34,211,238,0.18), rgba(34,211,238,0.05));
  border-color: rgba(34, 211, 238, 0.5);
  color: var(--cyan);
  font-weight: 700;
}
.btn-primary.live {
  background: linear-gradient(135deg, rgba(244,63,94,0.2), rgba(244,63,94,0.05));
  border-color: rgba(244, 63, 94, 0.6);
  color: var(--magenta);
}

/* ---------- source select + number fields ---------- */
.source-select {
  background: #182136;
  color: var(--text);
  border: 1px solid var(--panel-edge);
  border-radius: 8px;
  padding: 8px 10px;
  font-family: var(--mono);
  font-size: 12px;
  max-width: 230px;
  cursor: pointer;
}
.source-select:hover { border-color: var(--cyan); }

.field label {
  display: block;
  font-size: 10px;
  letter-spacing: 2px;
  color: var(--text-dim);
  font-family: var(--mono);
  margin-bottom: 5px;
}
.field input[type="number"] {
  width: 100%;
  background: #0a0f1a;
  border: 1px solid var(--panel-edge);
  color: var(--text);
  font-family: var(--mono);
  font-size: 14px;
  padding: 7px 9px;
  border-radius: 8px;
}
.field input[type="number"]:focus { outline: none; border-color: var(--cyan); }
.field input[type="range"] { width: 100%; accent-color: var(--cyan); margin: 10px 0 4px; }

/* ---------- metronome ---------- */
.metro-visual {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 4px 0;
}
.metro-beat {
  font-family: var(--mono);
  font-size: 58px;
  font-weight: 700;
  line-height: 1;
  color: var(--text-dim);
  font-variant-numeric: tabular-nums;
  transition: color 70ms;
}
.metro-beat.pulse { color: var(--cyan); text-shadow: 0 0 24px rgba(34, 211, 238, 0.5); }
.metro-beat.pulse-accent { color: var(--magenta); text-shadow: 0 0 24px rgba(244, 63, 94, 0.5); }

.metro-dots { display: flex; gap: 9px; min-height: 12px; }
.metro-dots .dot {
  width: 12px; height: 12px; border-radius: 50%;
  background: #1e2740;
  transition: background 70ms, box-shadow 70ms;
}
.metro-dots .dot.on { background: var(--cyan); box-shadow: 0 0 10px var(--cyan); }
.metro-dots .dot.on-accent { background: var(--magenta); box-shadow: 0 0 12px var(--magenta); }

.metro-controls {
  display: grid;
  grid-template-columns: 1fr 1fr 1.2fr;
  gap: 10px;
  align-items: end;
}

/* ---------- delay calculator ---------- */
.calc-bpm-row { display: flex; gap: 8px; align-items: flex-end; }
.calc-bpm-row .field { flex: 1; }
.calc-bpm-row .btn { flex: none; padding: 9px 16px; }

.calc-table-wrap { overflow-x: auto; }
.calc-table { width: 100%; border-collapse: collapse; font-family: var(--mono); }
.calc-table th {
  font-size: 10px;
  color: var(--text-dim);
  letter-spacing: 1.5px;
  text-align: left;
  padding: 6px 9px;
  border-bottom: 1px solid var(--panel-edge);
  font-weight: 600;
}
.calc-table td {
  padding: 7px 9px;
  border-bottom: 1px solid rgba(30, 39, 64, 0.5);
  font-size: 13px;
}
.calc-table .note-name { color: var(--text-dim); font-size: 12px; }
.calc-cell { cursor: pointer; }
.calc-cell:hover { background: rgba(34, 211, 238, 0.07); }
.calc-cell .hz { display: block; font-size: 10px; color: var(--text-dim); }
.calc-cell.copied .ms { color: var(--green); }

/* ---------- flash overlay ---------- */
#flashOverlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background: var(--cyan);
  opacity: 0;
  z-index: 50;
}
#flashOverlay.hit { animation: screenflash 130ms ease-out; }
#flashOverlay.hit.downbeat { background: #f2f6ff; }
@keyframes screenflash {
  0% { opacity: 0.45; }
  100% { opacity: 0; }
}

/* ---------- beat dot ---------- */
.beat-dot {
  width: 14px; height: 14px; border-radius: 50%;
  background: #1e2740;
  transition: background 60ms, box-shadow 60ms;
}
.beat-dot.flash {
  background: var(--cyan);
  box-shadow: 0 0 16px var(--cyan), 0 0 40px rgba(34, 211, 238, 0.5);
}

/* ---------- confidence + slider ---------- */
.conf-block label, .slider-block label {
  display: block;
  font-size: 10px;
  letter-spacing: 2px;
  color: var(--text-dim);
  margin-bottom: 6px;
  font-family: var(--mono);
}
.conf-bar {
  height: 8px; border-radius: 4px;
  background: #0a0f1a;
  border: 1px solid var(--panel-edge);
  overflow: hidden;
}
.conf-fill {
  height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--magenta), var(--amber), var(--green));
  transition: width 200ms ease;
}

.slider-block input[type="range"] {
  width: 100%;
  accent-color: var(--cyan);
}

/* ---------- canvases ---------- */
#spectrumCanvas, #scopeCanvas {
  width: 100%;
  display: block;
  border-radius: 8px;
  background: #0a0f1a;
  border: 1px solid var(--panel-edge);
}
#spectrumCanvas { height: 260px; }
#scopeCanvas { height: 64px; }

/* ---------- footer ---------- */
.app-footer {
  text-align: center;
  font-size: 11px;
  color: var(--text-dim);
  padding: 12px;
  border-top: 1px solid var(--panel-edge);
}

@media (max-width: 800px) {
  .grid { grid-template-columns: 1fr; }
  .bpm-value { font-size: 60px; }
}