:root {
  --bg: #efe7d0;
  --panel: #f9f3e5;
  --panel-edge: #d7c7a2;
  --paper: #fffdfa;
  --paper-shadow: rgba(84, 56, 16, 0.18);
  --ink: #2b2010;
  --accent: #b55d2e;
  --accent-deep: #8f3f17;
  --line: #67543a;
  --grid: #766346;
  --muted: #7f6b4a;
  --danger: #8e3831;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(255, 255, 255, 0.45), transparent 28%),
    linear-gradient(160deg, #eadfbf 0%, #e6d0aa 45%, #d2b789 100%);
  font-family: "Kosugi Maru", "Microsoft JhengHei", sans-serif;
}

body {
  min-height: 100vh;
}

button,
input,
textarea {
  font: inherit;
}

.app-shell {
  display: grid;
  grid-template-columns: minmax(320px, 420px) 1fr;
  min-height: 100vh;
}

.app-footer {
  position: fixed;
  right: 14px;
  bottom: 12px;
  width: min(380px, calc(100vw - 28px));
  display: block;
  padding: 10px 12px;
  border-radius: 14px;
  border: 1px solid rgba(117, 94, 50, 0.22);
  background: rgba(255, 252, 246, 0.85);
  color: rgba(70, 53, 24, 0.82);
  font-size: 0.88rem;
  line-height: 1.3;
  backdrop-filter: blur(10px);
  box-shadow: 0 12px 30px rgba(109, 80, 27, 0.08);
  z-index: 40;
}

.app-footer-stack {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 4px;
  text-align: right;
}

.app-footer-row {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
}

.app-footer-license {
  font-size: 0.8rem;
  color: rgba(70, 53, 24, 0.72);
}

.app-footer a {
  color: var(--accent-deep);
  text-decoration: none;
  font-weight: 700;
}

.app-footer a:hover {
  text-decoration: underline;
}

.footer-sep {
  color: rgba(117, 94, 50, 0.5);
}

.control-panel {
  padding: 24px 22px 28px;
  background: linear-gradient(180deg, rgba(255, 250, 240, 0.95), rgba(247, 237, 216, 0.96));
  border-right: 1px solid rgba(117, 94, 50, 0.26);
  overflow-y: auto;
  backdrop-filter: blur(10px);
}

.panel-header h1,
.panel-section h2,
.mask-list-wrap h3 {
  font-family: "Noto Serif TC", serif;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--accent-deep);
  font-size: 0.76rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.panel-header h1 {
  margin: 0;
  font-size: 1.9rem;
}

.panel-copy {
  margin: 10px 0 0;
  line-height: 1.7;
  color: var(--muted);
}

.panel-section {
  margin-top: 22px;
  padding: 16px;
  background: rgba(255, 252, 246, 0.82);
  border: 1px solid var(--panel-edge);
  border-radius: 18px;
  box-shadow: 0 10px 30px rgba(109, 80, 27, 0.06);
}

.panel-section h2,
.mask-list-wrap h3 {
  margin: 0 0 12px;
  font-size: 1.02rem;
}

label {
  display: block;
  margin-top: 12px;
  font-size: 0.95rem;
}

.inline-actions {
  display: flex;
  justify-content: flex-end;
  margin-top: 8px;
}

.small-button {
  min-height: 34px;
  padding: 6px 14px;
  font-size: 0.88rem;
}

input,
textarea {
  width: 100%;
  margin-top: 6px;
  padding: 10px 12px;
  border: 1px solid rgba(108, 89, 52, 0.28);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.85);
  color: var(--ink);
}

textarea {
  resize: vertical;
  line-height: 1.5;
}

.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.tool-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 10px;
}

button,
.button-like {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  min-height: 42px;
  padding: 10px 14px;
  border: 0;
  border-radius: 999px;
  background: linear-gradient(180deg, var(--accent), #a44d21);
  color: #fffaf6;
  cursor: pointer;
  text-decoration: none;
  box-shadow: 0 10px 18px rgba(135, 68, 23, 0.18);
}

button.secondary,
.button-like.secondary {
  background: linear-gradient(180deg, #f2e7cf, #e5d3ab);
  color: var(--ink);
  box-shadow: none;
}

button.danger {
  background: linear-gradient(180deg, #b5524c, var(--danger));
}

button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.selected-cell-label,
.hint {
  margin: 0;
  line-height: 1.6;
  color: var(--muted);
}

.selected-cell-label {
  font-weight: 700;
  color: var(--accent-deep);
}

.mask-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.mask-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 10px 12px;
  border: 1px dashed rgba(110, 85, 37, 0.3);
  border-radius: 12px;
}

.mask-item-label {
  font-size: 0.9rem;
}

.preview-area {
  padding: 28px;
  overflow: auto;
}

.page-frame {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  min-height: calc(100vh - 56px);
}

.worksheet-page {
  width: min(96vw, 1200px);
  aspect-ratio: 297 / 210;
  display: flex;
  flex-direction: column;
  background:
    linear-gradient(180deg, rgba(250, 242, 219, 0.72), rgba(255, 253, 246, 0.94) 120px),
    var(--paper);
  border-radius: 20px;
  box-shadow:
    0 24px 60px var(--paper-shadow),
    inset 0 0 0 1px rgba(123, 95, 41, 0.18);
  padding: 28px 28px 24px;
  position: relative;
}

.worksheet-header {
  margin-bottom: 18px;
}

.worksheet-title {
  margin: 0;
  text-align: center;
  font-family: "Noto Serif TC", serif;
  font-size: clamp(1.6rem, 2vw, 2.3rem);
  letter-spacing: 0.14em;
}

.worksheet-subtitle {
  margin: 8px 0 0;
  text-align: center;
  font-size: 1rem;
  color: var(--muted);
}

.worksheet-instruction {
  margin: 18px 0 0;
  padding: 10px 16px;
  border-radius: 999px;
  background: rgba(250, 246, 236, 0.92);
  border: 1px solid rgba(114, 94, 51, 0.2);
  font-size: 0.95rem;
  line-height: 1.7;
}

.worksheet-grid {
  display: grid;
  width: 100%;
  max-width: 100%;
  border-top: 1.5px solid var(--grid);
  border-left: 1.5px solid var(--grid);
  justify-self: center;
  align-self: flex-start;
}

.cell {
  --annotation-width: 28%;
  --main-side-padding: 4%;
  position: relative;
  background: rgba(255, 255, 255, 0.7);
  border-right: 1.5px solid var(--grid);
  border-bottom: 1.5px solid var(--grid);
  overflow: hidden;
  user-select: none;
  aspect-ratio: 1 / 1;
}

.cell::after {
  content: "";
  position: absolute;
  top: -1.5px;
  right: -1.5px;
  bottom: -1.5px;
  width: var(--annotation-width);
  border-left: 1.5px solid var(--grid);
  background: rgba(255, 255, 255, 0.48);
  pointer-events: none;
}

.cell.blank {
  background:
    linear-gradient(180deg, rgba(250, 246, 235, 0.72), rgba(255, 255, 255, 0.86));
}

.cell.editable {
  cursor: crosshair;
}

.cell.selected {
  outline: 3px solid rgba(181, 93, 46, 0.85);
  outline-offset: -3px;
}

.cell-char {
  position: absolute;
  top: 8%;
  left: var(--main-side-padding);
  bottom: 10%;
  width: calc(100% - var(--annotation-width) - (var(--main-side-padding) * 2));
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "Noto Serif TC", serif;
  font-size: clamp(2.7rem, 4vw, 4.5rem);
  font-weight: 700;
  line-height: 1;
}

.cell-svg {
  position: absolute;
  top: 8%;
  left: var(--main-side-padding);
  bottom: 10%;
  width: calc(100% - var(--annotation-width) - (var(--main-side-padding) * 2));
  height: 82%;
  overflow: visible;
}

.stroke-path {
  fill: #1d1509;
}

.stroke-path.hidden {
  fill: transparent;
}

.cell-annotation {
  position: absolute;
  top: -1.5px;
  right: -1.5px;
  bottom: -1.5px;
  width: var(--annotation-width);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4px 8px 4px 4px;
  background: rgba(255, 255, 255, 0.18);
  font-size: 0.78rem;
  line-height: 1.05;
  color: #8a7a58;
  text-align: center;
  z-index: 1;
}

.cell-annotation-body {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  min-height: 100%;
}

.cell-annotation-char {
  display: block;
  line-height: 1;
}

.cell-annotation-tone {
  position: absolute;
  right: 1px;
  top: 50%;
  transform: translateY(-50%);
  line-height: 1;
  font-size: 0.76rem;
}

.cell-annotation-tone-light {
  left: 50%;
  right: auto;
  top: 16px;
  transform: translateX(-50%);
}

.mask-layer {
  position: absolute;
  top: 8%;
  left: 7%;
  bottom: 10%;
  width: 70%;
  pointer-events: none;
}

.mask-rect {
  position: absolute;
  background: rgba(255, 255, 255, 0.98);
  border-radius: 4px;
  border: 1px solid rgba(255, 255, 255, 0.92);
  box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.5);
}

.draft-mask {
  position: absolute;
  border: 2px dashed rgba(181, 93, 46, 0.95);
  background: rgba(247, 208, 174, 0.35);
  pointer-events: none;
}

.footer-badge {
  position: absolute;
  right: 22px;
  bottom: 16px;
  font-size: 0.78rem;
  color: #9b8c6e;
}

.stroke-editor-modal {
  position: fixed;
  inset: 0;
  z-index: 50;
}

.stroke-editor-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(35, 23, 7, 0.48);
  backdrop-filter: blur(4px);
}

.stroke-editor-panel {
  position: relative;
  display: flex;
  flex-direction: column;
  width: min(1100px, calc(100vw - 48px));
  max-height: calc(100vh - 48px);
  margin: 24px auto;
  padding: 20px;
  border-radius: 24px;
  background: linear-gradient(180deg, rgba(255, 250, 240, 0.98), rgba(249, 240, 220, 0.98));
  box-shadow: 0 30px 80px rgba(39, 24, 4, 0.28);
}

.stroke-editor-header {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: flex-start;
}

.stroke-editor-header h2 {
  margin: 0;
  font-family: "Noto Serif TC", serif;
  font-size: 1.6rem;
}

.stroke-editor-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 18px;
  margin-top: 16px;
  min-height: 0;
  overflow: hidden;
}

.stroke-editor-canvas {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 420px;
  border-radius: 22px;
  border: 1px solid rgba(110, 85, 37, 0.22);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.95), rgba(247, 238, 221, 0.92)),
    #fff;
}

.stroke-editor-canvas svg {
  width: min(100%, 640px);
  height: auto;
  aspect-ratio: 1 / 1;
}

.editor-stroke {
  fill: #1c1409;
  cursor: pointer;
  transition: fill 120ms ease, opacity 120ms ease;
}

.editor-stroke:hover {
  fill: #b55d2e;
}

.editor-stroke.hidden {
  fill: rgba(28, 20, 9, 0.12);
}

.stroke-editor-sidebar {
  overflow: auto;
}

@media (max-width: 960px) {
  .stroke-editor-panel {
    width: calc(100vw - 20px);
    max-height: calc(100vh - 20px);
    margin: 10px auto;
    padding: 14px;
  }

  .stroke-editor-body {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 1100px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .preview-area {
    padding-top: 12px;
  }
}

@media print {
  @page {
    size: A4 landscape;
    margin: 0;
  }

  html,
  body {
    background: #fff;
  }

  .print-hidden {
    display: none !important;
  }

  .preview-area {
    padding: 0;
    overflow: visible;
  }

  .page-frame {
    min-height: auto;
  }

  .worksheet-page {
    width: 297mm;
    height: 210mm;
    border-radius: 0;
    box-shadow: none;
    margin: 0;
    padding: 12mm 12mm 10mm;
  }
}