:root {
  --bg: #ffffff;
  --card: #ffffff;
  --primary: #2b7fff;
  --text: #1a1a1a;
  --accent: #fb2c36;
  --muted: #666666;
  --border: #d6d6d6;
  --surface: #ffffff;
  --surface-hover: #f5f5f5;
  --indicator-idle: #9a9a9a;
  --focus-outline: rgba(37, 99, 235, 0.45);
  --focus-border: rgba(37, 99, 235, 0.5);
  --danger-border: rgba(239, 68, 68, 0.55);
  --radius-sm: 10px;
  --radius: 12px;
  --ring: 0 0 0 3px rgba(37, 99, 235, 0.24);
  --content-max-width: 980px;
  --control-height: 32px;
}
body {
  font-family: -apple-system, system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-color: var(--bg);
  color: var(--text);
  margin: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  min-height: 100vh;
}
.container {
  width: 95%;
  max-width: 1100px;
  margin-top: 1.5rem;
  padding: 0;
}
.topbar {
  position: sticky;
  top: 12px;
  z-index: 10;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px;
  margin-bottom: 1rem;
  width: 100%;
  max-width: var(--content-max-width);
  margin-inline: auto;
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.brand {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
  align-items: center;
  text-align: center;
}
.brand__title {
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.1;
  font-size: 1.1rem;
}
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--card);
  border: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.controls-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.3fr) minmax(160px, 200px);
  gap: 10px;
  align-items: stretch;
  max-width: 100%;
}
.panel {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  display: flex;
  align-items: center;
  gap: 12px;
  height: 100%;
  box-sizing: border-box;
  min-width: 0;
}
.panel__header {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  font-weight: 600;
  white-space: nowrap;
}
.panel--record {
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
}
.panel--record .record-row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: center;
}
.summary-item {
  text-align: center;
}
.summary-item .stat-label {
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
}
.summary-item .stat-value {
  font-size: 1rem;
}
.setting {
  display: flex;
  align-items: center;
  gap: 6px;
}
.setting label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
  white-space: nowrap;
}
.panel--csv .button-row {
  display: flex;
  flex-direction: column;
  gap: 10px;
  width: 100%;
}
.panel--csv {
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  text-align: center;
}
.panel--csv .btn {
  width: 100%;
}
.segmented {
  display: inline-flex;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: var(--surface);
}
.segmented__item {
  position: relative;
  cursor: pointer;
  user-select: none;
}
.segmented__item input {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}
.segmented__item span {
  display: flex;
  align-items: center;
  justify-content: center;
  height: var(--control-height);
  padding: 0 10px;
  font-size: 0.85rem;
  line-height: 1;
  white-space: nowrap;
  font-weight: 500;
}
.segmented__item + .segmented__item span {
  border-left: 1px solid var(--border);
}
.segmented__item input:checked + span {
  background: var(--surface-hover);
  color: var(--primary);
}
.segmented__item input:disabled + span {
  opacity: 0.55;
  cursor: not-allowed;
}
.segmented__item input:focus-visible + span {
  outline: 2px solid var(--focus-outline);
  outline-offset: -2px;
}

.btn {
  appearance: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: var(--control-height);
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  border-radius: var(--radius-sm);
  padding: 0 10px;
  font-size: 0.85rem;
  line-height: 1;
  cursor: pointer;
  user-select: none;
}
.btn:hover {
  border-color: var(--focus-outline);
  background: var(--surface-hover);
}
.btn:focus-visible {
  outline: 2px solid var(--focus-outline);
  outline-offset: 2px;
}
.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.unsupported {
  color: var(--accent);
  text-decoration: line-through;
  text-decoration-thickness: 2px;
}
#statusIndicator {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-weight: 700;
  padding: 10px 16px;
  border-radius: 999px;
  background: var(--card);
  border: 1px solid var(--border);
  text-align: center;
  font-size: 0.85rem;
  width: 100%;
  box-sizing: border-box;
  cursor: pointer;
  user-select: none;
}
#statusIndicator:hover:not(.recording) {
  background: var(--surface-hover);
  border-color: var(--focus-outline);
}
#statusIndicator::before {
  content: "";
  width: 9px;
  height: 9px;
  border-radius: 999px;
  background: var(--indicator-idle);
  flex: 0 0 auto;
}
.recording {
  background: var(--accent) !important;
  color: white;
  border-color: var(--danger-border) !important;
}
.recording::before {
  background: var(--surface);
}
.stat-value {
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}
:is(input, select).stat-value {
  font: inherit;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  box-sizing: border-box;
  text-align: center;
  font-size: 0.85rem;
  line-height: 1;
  height: var(--control-height);
  padding: 0 10px;
}
:is(input, select).stat-value:focus-visible {
  outline: none;
  box-shadow: var(--ring);
  border-color: var(--focus-border);
}
input.stat-value {
  width: min(100%, 12rem);
  margin-inline: auto;
  display: block;
}
/* Remove number-input spinners so centered text is visually centered. */
input[type="number"].stat-value {
  appearance: textfield;
  -moz-appearance: textfield;
}
input[type="number"].stat-value::-webkit-outer-spin-button,
input[type="number"].stat-value::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}
select.stat-value {
  cursor: pointer;
  width: min(100%, 12rem);
  margin-inline: auto;
  display: block;
}

@media (max-width: 900px) {
  .controls-grid {
    grid-template-columns: 1fr;
  }
}
@media (max-width: 600px) {
  .panel {
    justify-content: center;
  }
  .panel--record {
    align-items: center;
  }
}

.panel--mid {
  align-items: stretch;
  flex-direction: column;
  gap: 10px;
}
.mid-section {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.mid-section--summary,
.mid-section--settings {
  display: grid;
  grid-template-columns: 80px 1fr;
  align-items: center;
  column-gap: 12px;
  row-gap: 6px;
}
.mid-section--summary .panel__header,
.mid-section--settings .panel__header {
  justify-self: end;
  padding-right: 2px;
}
.mid-section--settings {
  padding-top: 10px;
  border-top: 1px solid var(--border);
}
.mid-summary-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  justify-items: center;
  width: 100%;
}
.mid-settings-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  align-items: center;
  width: 100%;
}
.mid-settings-row .setting {
  display: grid;
  grid-template-columns: 1fr;
  grid-template-rows: auto auto;
  justify-items: center;
  align-content: center;
  row-gap: 6px;
}
.mid-settings-row .setting label {
  justify-self: center;
}
#periodSelect {
  width: 15ch;
}
#dpiInput {
  width: 10ch;
}

.plot-card {
  margin-top: 16px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px;
  width: 100%;
  max-width: var(--content-max-width);
  margin-inline: auto;
  box-sizing: border-box;
}
#plot {
  /* On wide screens: content box becomes 960px (980px card - 20px padding). */
  width: 100%;
  aspect-ratio: 4 / 3; /* 960x720 */
}

/* If the viewport is short, don't use a sticky topbar (which would cause the plot
   to scroll underneath it). Keep normal document flow and let the full page scroll. */
@media (max-height: 700px), (max-width: 900px) {
  .topbar {
    position: static;
  }
  #plot {
    max-height: max(280px, calc(100vh - 260px));
  }
}
@media (prefers-reduced-motion: reduce) {
  * {
    transition: none !important;
    scroll-behavior: auto !important;
  }
}