:root {
  --bg: #f4f5f7;
  --card: #ffffff;
  --text: #1c1e21;
  --muted: #5f646b;
  --border: #dfe2e6;
  --accent: #1f5fa8;
  --ok: #1a7f37;
  --bad: #b42318;
  --warn-bg: #fff4e0;
  --warn: #8a5a00;
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.45;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
}

.app {
  max-width: 1100px;
  margin: 0 auto;
  padding: 16px 16px 48px;
}

.app-header h1 {
  margin: 8px 0 4px;
  font-size: 1.7rem;
}

.app-header p,
.hint {
  color: var(--muted);
  margin: 0 0 14px;
  max-width: 75em;
}

.app-footer {
  color: var(--muted);
  font-size: 0.85rem;
  margin-top: 16px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px 16px 16px;
  margin-bottom: 16px;
}

.card h2 {
  margin: 0 0 10px;
  font-size: 1.15rem;
}

.card.status {
  color: var(--muted);
}

.plot {
  display: block;
  width: 100%;
  background: #fff;
}

.line-plot {
  height: 170px;
}

.waveform-plot {
  height: 130px;
  margin-top: 6px;
}

.spectrogram-plot {
  height: 240px;
}

.spectrograms {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(420px, 1fr));
  gap: 8px;
}

.response-plots {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 8px 16px;
  margin-top: 8px;
}

.plot-label {
  font-size: 0.8rem;
  color: var(--muted);
  margin: 10px 0 2px;
}

.button-row {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.divider {
  width: 1px;
  height: 22px;
  background: var(--border);
  margin: 0 4px;
}

button {
  font: inherit;
  font-size: 0.9rem;
  padding: 6px 12px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  cursor: pointer;
}

button:hover:not(:disabled) {
  background: #f0f2f5;
}

button:disabled {
  opacity: 0.5;
  cursor: default;
}

button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

button.primary:hover:not(:disabled) {
  background: #184c87;
}

button.selected {
  border-color: var(--accent);
  box-shadow: inset 0 0 0 1px var(--accent);
  font-weight: 600;
}

.playing-indicator {
  color: var(--muted);
  font-size: 0.9rem;
  min-width: 8em;
}

.view-controls {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin: 10px 0 2px;
}

.spacer {
  flex: 1;
}

button.small {
  font-size: 0.8rem;
  padding: 4px 10px;
}

.global-controls,
.zoom-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  align-items: center;
  margin: 6px 0;
}

.global-controls label,
.zoom-controls label,
.scrub {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
}

.global-controls label > span:first-child,
.zoom-controls label > span:first-child,
.scrub > span:first-child {
  white-space: nowrap;
}

.zoom-controls .grow {
  flex: 1;
  min-width: 260px;
}

.scrub {
  margin: 10px 0 4px;
}

.scrub input[type='range'] {
  flex: 1;
  max-width: 480px;
}

.wide-range {
  width: 220px;
}

.info {
  color: var(--muted);
  font-size: 0.85rem;
  white-space: nowrap;
}

select {
  font: inherit;
  font-size: 0.9rem;
  padding: 4px 6px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: #fff;
}

input[type='range'] {
  min-width: 80px;
  accent-color: var(--accent);
}

.slider-value {
  font: inherit;
  font-size: 0.85rem;
  width: 5.5em;
  padding: 2px 4px;
  border: 1px solid var(--border);
  border-radius: 4px;
}

.slider-unit {
  color: var(--muted);
  font-size: 0.85rem;
  white-space: nowrap;
}

.source-info {
  margin-top: 10px;
  font-size: 0.9rem;
  color: var(--muted);
}

.error {
  color: var(--bad);
  margin-top: 8px;
  font-size: 0.9rem;
}

.warning {
  background: var(--warn-bg);
  color: var(--warn);
  border-radius: 6px;
  padding: 8px 10px;
  margin: 8px 0;
  font-size: 0.9rem;
}