:root {
  --bg: #ffffff;
  --surface: #f4f6f8;
  --fg: #1b1f24;
  --muted: #58616b;
  --link: #0a58a8;
  --accent: #0a58a8;
  --border: #848d97;
  --bar: #1b1f24;
  --warn-fg: #7a3b00;
  --warn-bg: #fff3e0;
  --ok-fg: #0f5132;
  --ok-bg: #e6f4ec;
  --cover-fg: #ffffff;
  --cover-bg: #1b1f24;
}

*, *::before, *::after {
  box-sizing: border-box;
}

body {
  margin: 0 auto;
  max-width: 1080px;
  min-height: 100dvh;
  padding: 16px;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", sans-serif;
  overflow-wrap: anywhere;
}

h1 {
  text-align: center;
  letter-spacing: 0.03em;
  margin: 0.5rem 0;
}

h2 {
  font-size: 1.25rem;
  margin: 1.5rem 0 0.75rem;
}

section {
  margin-block: 1.5rem;
}

.page-header, footer {
  border-block-end: 1px solid var(--border);
  padding-block: 0.5rem;
}

footer {
  border-block-start: 1px solid var(--border);
  border-block-end: 0;
  margin-block-start: 2rem;
  color: var(--muted);
  font-size: 0.875rem;
}

.privacy {
  background: var(--surface);
  padding: 0.75rem;
  border-inline-start: 3px solid var(--accent);
}

.lesson-toc {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 16rem), 1fr));
  gap: 8px;
  margin-block: 1rem;
}

.lesson-toc button {
  text-align: start;
}

[data-quiz-return] {
  margin-block-end: 0.5rem;
}

button, input, textarea, select {
  font: inherit;
  color: inherit;
  background: var(--bg);
  min-height: 44px;
  min-width: 44px;
  border: 1px solid var(--border);
  border-radius: 4px;
}

button {
  cursor: pointer;
  padding: 0.4rem 0.75rem;
}

button:disabled {
  cursor: default;
  color: var(--muted);
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

label {
  display: block;
  font-weight: 600;
}

#sample-select, textarea {
  width: 100%;
  min-width: 0;
  padding: 0.5rem;
}

textarea {
  resize: vertical;
  font-family: ui-monospace, Consolas, monospace;
}

.muted, .legend {
  color: var(--muted);
  font-size: 0.875rem;
}

#bar-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(138px, 1fr));
  gap: 8px;
  align-items: start;
}

#panel-decode {
  overflow-anchor: none;
}

.bar-card {
  width: 138px;
  border: 1px solid var(--border);
  padding: 2px;
  background: var(--surface);
  border-radius: 4px;
}

.bar-card.marker-card {
  width: 94px;
}

.card-heading, .card-range, .card-symbol {
  margin: 0;
  text-align: center;
  font-size: 0.875rem;
}

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

.card-bars {
  display: flex;
  gap: 0;
}

.bar-button {
  width: 44px;
  min-width: 44px;
  height: 64px;
  flex: 0 0 44px;
  border: 0;
  border-radius: 0;
  padding: 2px;
  box-shadow: inset 0 0 0 1px var(--border);
  scroll-margin-bottom: var(--palette-space, 8px);
}

.bar-button[aria-pressed="true"] {
  box-shadow: inset 0 0 0 4px var(--accent);
}

.bar-button:focus-visible {
  outline: 2px dashed var(--accent);
  outline-offset: -6px;
}

.bar-button svg {
  display: block;
  width: 36px;
  height: 54px;
}

.palette-dock {
  position: sticky;
  bottom: 0;
  background: var(--surface);
  border-block: 1px solid var(--border);
  padding-block: 6px;
  margin-block-start: 12px;
  z-index: 2;
}

#bar-palette {
  display: flex;
  justify-content: center;
  gap: 8px;
}

.palette-button {
  width: 44px;
  height: 44px;
  padding: 2px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.palette-button svg {
  width: 22px;
  height: 34px;
}

.palette-dock p {
  margin: 4px 0 0;
  text-align: center;
}

svg {
  color: var(--bar);
  font-family: Meiryo, "Yu Gothic", sans-serif;
}

.bar-shape {
  fill: currentColor;
}

.empty-bar, .unknown-bar {
  fill: var(--bg);
  stroke: currentColor;
  stroke-width: 0.5;
}

.empty-bar {
  stroke-dasharray: 1 1;
}

.hatch {
  stroke: currentColor;
  stroke-width: 0.4;
}

.unknown-mark {
  font-size: 6px;
  fill: currentColor;
  text-anchor: middle;
}

.overview-svg {
  display: block;
  width: 100%;
  height: auto;
}

.band {
  fill: var(--surface);
  stroke: var(--border);
}

.band-postal {
  fill: var(--bg);
  stroke-dasharray: 5 3;
}

.band-label {
  font-size: 18px;
  text-anchor: middle;
  fill: var(--fg);
}

.band-symbol {
  font-size: 12px;
  text-anchor: middle;
  fill: var(--fg);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  clip-path: inset(50%);
  overflow: hidden;
  white-space: nowrap;
}

[hidden] {
  display: none !important;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-block: 8px;
}

.actions button {
  max-width: 100%;
}

.range-inputs {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
  margin-bottom: 8px;
}

.range-inputs input {
  width: 100%;
  padding: 6px;
}

.judgment {
  border-inline-start: 4px solid var(--accent);
  padding-inline-start: 12px;
  font-size: 1.25rem;
  font-weight: 700;
}

.readable dd {
  margin: 0 0 12px;
  font-size: 1.5rem;
  font-family: ui-monospace, Consolas, monospace;
}

.value-token {
  display: inline-block;
  max-width: 100%;
  vertical-align: bottom;
}

.calculated-mark {
  display: block;
  font: 0.75rem/1.4 system-ui, sans-serif;
  text-align: center;
  color: var(--warn-fg);
  background: var(--warn-bg);
}

.inspection-label {
  display: inline;
  font-size: 0.875rem;
  padding: 1px 3px;
  border-radius: 3px;
}

.inspection-label.warn {
  color: var(--warn-fg);
  background: var(--warn-bg);
}

.inspection-label.ok {
  color: var(--fg);
  background: var(--surface);
  border: 1px solid var(--border);
}

.inspection-list .inspection-label, #breakdown .inspection-label {
  white-space: nowrap;
}

.card-symbol .inspection-label {
  display: inline-flex;
  flex-wrap: wrap;
  justify-content: center;
  max-width: 100%;
  column-gap: 0.25em;
}

.inspection-state, .candidate-count {
  white-space: nowrap;
}

.inspection-list {
  padding-inline-start: 1.5rem;
}

.inspection-list li {
  margin-block: 4px;
}

.overview-inspection {
  text-anchor: middle;
  font-size: 15px;
  fill: var(--fg);
}

.overview-inspection.warn {
  fill: var(--warn-fg);
}

.overview-inspection.ok {
  fill: var(--muted);
}

.inspection-background.warn {
  fill: var(--warn-bg);
}

.inspection-background.ok {
  fill: var(--surface);
}

.mini-bars {
  display: inline-block;
  width: 54px;
  height: 54px;
  vertical-align: middle;
  margin-right: 8px;
}

#breakdown {
  width: 100%;
  border-collapse: collapse;
}

#breakdown thead {
  display: none;
}

#breakdown tr, #breakdown td, #breakdown tbody {
  display: block;
}

#breakdown tr {
  border-block-start: 1px solid var(--border);
  padding-block: 8px;
}

#breakdown td {
  padding: 4px 0;
}

#breakdown td::before {
  content: attr(data-label);
  display: inline-block;
  min-width: 6rem;
  font-weight: 600;
  margin-right: 8px;
}

#breakdown button {
  display: block;
  margin-block: 8px;
  max-width: 100%;
}

@media (min-width: 48rem) {
  #breakdown thead {
    display: table-header-group;
  }

  #breakdown tbody {
    display: table-row-group;
  }

  #breakdown tr {
    display: table-row;
  }

  #breakdown td, #breakdown th {
    display: table-cell;
    text-align: left;
    padding: 8px;
    vertical-align: top;
  }

  #breakdown td::before {
    display: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto !important;
    transition: none !important;
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #0f1419;
    --surface: #1a2129;
    --fg: #e6edf3;
    --muted: #a3adb8;
    --link: #7cb8f7;
    --accent: #7cb8f7;
    --border: #6b7682;
    --bar: #e6edf3;
    --warn-fg: #ffd7a3;
    --warn-bg: #3a2400;
    --ok-fg: #b5ecc9;
    --ok-bg: #10301f;
    --cover-fg: #0f1419;
    --cover-bg: #a3adb8;
  }
}

.language-row {
  display: flex;
  justify-content: flex-end;
}

.tabs {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 4px;
  margin-block: 1rem;
}

[role="tab"] {
  grid-column: span 2;
  min-width: 44px;
  padding-inline: 0.25rem;
  font-size: 0.875rem;
  white-space: nowrap;
}

[role="tab"]:nth-last-child(-n + 2) {
  grid-column: span 3;
}

@media (min-width: 30rem) {
  .tabs {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  [role="tab"], [role="tab"]:nth-last-child(-n + 2) {
    grid-column: auto;
  }
}

@media (min-width: 48rem) {
  [role="tab"] {
    font-size: 1rem;
    padding-inline: 0.75rem;
  }
}

[role="tab"][aria-selected="true"] {
  color: var(--bg);
  background: var(--accent);
  border-color: var(--accent);
}

summary {
  min-width: 44px;
  min-height: 44px;
  padding: 0.5rem;
  cursor: pointer;
  border: 1px solid var(--border);
}

#issues button {
  display: block;
  margin-block: 0.5rem;
}

a {
  display: block;
  min-width: 44px;
  min-height: 44px;
  padding-block: 0.5rem;
  color: var(--link);
}

.learn-table {
  width: 100%;
  border-collapse: collapse;
  table-layout: fixed;
}

.learn-table th, .learn-table td {
  border: 1px solid var(--border);
  padding: 0.5rem;
  text-align: start;
  vertical-align: top;
}

.learn-table caption {
  text-align: start;
  font-weight: 600;
  margin-block: 0.5rem;
}

.lesson-bars {
  display: block;
  width: 100%;
  height: auto;
}

.symbol-table .lesson-bars {
  width: 72px;
  max-width: 100%;
  height: 40px;
}

.shape-legend {
  list-style: none;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 8px;
}

.shape-legend li {
  padding: 0.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
}

.shape-legend .lesson-bars {
  width: 24px;
  height: 40px;
  margin: 0 auto;
}

.formula-svg {
  display: block;
  max-width: 100%;
  width: 320px;
}

.formula-label {
  font-size: 22px;
  fill: currentColor;
}

.envelope, .extraction {
  padding: 0.75rem;
  border: 1px solid var(--border);
  background: var(--surface);
  margin-block: 1rem;
}

.covered-name {
  background: var(--cover-bg);
  color: var(--cover-fg);
  border: 1px solid var(--border);
  padding: 0.2rem 2rem;
}

fieldset {
  min-width: 0;
  margin: 1.5rem 0;
  padding: 0.75rem;
  border: 1px solid var(--border);
}

legend {
  font-weight: 600;
  max-width: 100%;
}

.quiz-option {
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 44px;
  min-height: 44px;
  margin-block: 8px;
  font-weight: 400;
}

input[type="radio"] {
  width: auto;
  height: auto;
  min-width: 0;
  min-height: 0;
  margin: 0;
  flex: 0 0 auto;
  accent-color: var(--accent);
}

.structure-bands {
  display: grid;
  grid-template-columns: 2fr 21fr 39fr 3fr 2fr;
  font-size: 12px;
  text-align: center;
}

.structure-band {
  min-width: 0;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--fg);
  padding-block: 0.5rem;
}

.structure-postal {
  background: var(--bg);
  border-style: dashed;
}

.structure-start, .structure-cd, .structure-stop {
  background: var(--accent);
  color: var(--bg);
}

.lab-controls {
  display: grid;
  gap: 0.5rem;
}

.lab-controls select {
  width: 100%;
  min-width: 44px;
  padding: 0.5rem;
}

.lab-canvas {
  display: block;
  width: 100%;
  image-rendering: pixelated;
  max-width: 100%;
  height: auto;
  margin-block: 1rem;
}

#photo-file {
  display: block;
  width: 100%;
  padding: 0.5rem;
}

.photo-help {
  margin-block: 1rem;
}

.photo-example {
  margin: 1rem 0;
}

.photo-example-bars {
  display: flex;
  justify-content: space-between;
  position: relative;
  height: 72px;
  max-width: 320px;
  margin-inline: auto;
  padding-inline: 12px;
}

.photo-example-bars::before {
  content: '';
  position: absolute;
  inset: 50% 0 auto;
  border-top: 2px dashed var(--accent);
}

.photo-example-bar {
  position: relative;
  width: 5px;
  height: 100%;
  background: var(--fg);
}

.photo-example-bar.upper {
  height: 62.5%;
}

.photo-example-bar.lower {
  height: 62.5%;
  align-self: flex-end;
}

.photo-example-bar.timing {
  height: 25%;
  align-self: center;
}

.photo-example-bar:first-child::after, .photo-example-bar:last-child::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 20px;
  height: 20px;
  border: 3px solid var(--accent);
  border-radius: 50%;
  box-shadow: 0 0 0 2px var(--bg);
}

.photo-example-ends {
  display: flex;
  justify-content: space-between;
  max-width: 320px;
  margin: 0.5rem auto;
}

.photo-progress {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.5rem;
  padding: 0;
  list-style-position: inside;
}

.photo-progress li {
  padding: 0.5rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow-wrap: anywhere;
}

.photo-progress [aria-current="step"] {
  border: 3px solid var(--accent);
  padding: calc(0.5rem - 2px);
  font-weight: 700;
}

.photo-step {
  font-weight: 700;
  scroll-margin-block: 1rem;
}

.photo-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-block: 0.75rem;
}

#photo-overview {
  width: auto;
  max-width: 100%;
  max-height: 50vh;
  margin-inline: auto;
}

.photo-canvas {
  display: block;
  border: 1px solid var(--border);
  width: 100%;
  height: auto;
  cursor: crosshair;
  touch-action: manipulation;
  margin-block: 1rem;
}

#photo-zoom, #photo-result {
  image-rendering: pixelated;
}

.photo-result-wrap {
  max-width: 100%;
  overflow-x: auto;
  border-block: 1px solid var(--border);
}

#photo-result {
  display: block;
  max-width: none;
  height: auto;
}

#photo-clear {
  margin-block: 0.75rem;
}

#photo-notice:empty, #photo-step:empty, #photo-position:empty {
  display: none;
}

.card-origins {
  display: flex;
  font-size: 0.875rem;
  text-align: center;
  color: var(--muted);
}

.card-origins > span {
  flex: 0 0 44px;
  width: 44px;
  padding-inline: 2px;
}

.decode-summary {
  border: 1px solid var(--border);
  padding: 1rem;
  background: var(--surface);
}

.decode-summary h2 {
  margin-block-start: 0;
  scroll-margin-block-start: 1rem;
}