:root {
  --bg: #f3f6fb;
  --panel: #ffffff;
  --panel-soft: #f8fbff;
  --text: #111827;
  --muted: #687385;
  --line: #dce5f1;
  --line-strong: #c8d5e6;
  --accent: #2563eb;
  --accent-dark: #1d4ed8;
  --accent-soft: #eaf2ff;
  --danger: #b42318;
  --shadow: 0 2px 12px rgba(15, 23, 42, 0.06);
  --shadow-strong: 0 18px 42px rgba(15, 23, 42, 0.09);
}

body[data-theme="light"] {
  color-scheme: light;
}

body[data-theme="dark"] {
  color-scheme: dark;
  --bg: #101722;
  --panel: #172033;
  --panel-soft: #111827;
  --text: #e6edf7;
  --muted: #9aa8ba;
  --line: #29364a;
  --line-strong: #40516a;
  --accent: #60a5fa;
  --accent-dark: #bfdbfe;
  --accent-soft: #183456;
  --danger: #fca5a5;
  --shadow: 0 2px 14px rgba(0, 0, 0, 0.28);
  --shadow-strong: 0 18px 42px rgba(0, 0, 0, 0.34);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: "Noto Sans SC", "Microsoft YaHei", Arial, sans-serif;
  transition: background 0.2s ease, color 0.2s ease;
}
button, select { font: inherit; }
button { -webkit-tap-highlight-color: transparent; }

.announcement-bar {
  padding: 18px 22px 0;
}
.announcement-inner {
  display: grid;
  grid-template-columns: 34px 1fr;
  gap: 12px;
  max-width: 1480px;
  margin: 0 auto;
  padding: 14px 16px;
  border: 1px solid #bfdbfe;
  border-left: 4px solid var(--accent);
  border-radius: 16px;
  background: #eff6ff;
  color: #1e3a8a;
  box-shadow: var(--shadow);
}
body[data-theme="dark"] .announcement-inner {
  border-color: #2f5f95;
  border-left-color: var(--accent);
  background: #10243a;
  color: #dbeafe;
}
.announcement-icon {
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent);
  color: #ffffff;
  font-weight: 800;
}
.announcement-inner strong {
  display: block;
  margin-bottom: 6px;
  font-size: 15px;
}
.announcement-inner ol {
  margin: 0;
  padding-left: 20px;
  display: grid;
  gap: 3px;
  font-size: 14px;
  line-height: 1.6;
}

.app {
  min-height: calc(100vh - 116px);
  display: grid;
  grid-template-columns: minmax(0, 1fr) 420px;
  gap: 22px;
  padding: 22px;
}

.preview-panel,
.control-panel {
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--panel);
  box-shadow: var(--shadow);
  transition: background 0.2s ease, border-color 0.2s ease;
}
.preview-panel {
  min-width: 0;
  display: flex;
  flex-direction: column;
  padding: 18px;
}
.preview-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
  padding: 2px 4px 14px;
}
.eyebrow {
  margin: 0 0 4px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}
.preview-header h1,
.panel-header h2 {
  margin: 0;
  font-size: 24px;
  line-height: 1.22;
}
.preview-tools {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 0 0 auto;
}
.preview-tools span {
  padding: 6px 10px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent-dark);
  font-size: 12px;
  font-weight: 800;
}
.pin-preview-button {
  display: none;
  min-height: 30px;
  padding: 0 10px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: var(--panel);
  color: var(--accent);
  cursor: pointer;
  font-size: 12px;
  font-weight: 800;
}
.pin-preview-button.is-active {
  border-color: var(--accent);
  background: var(--accent);
  color: #ffffff;
}
.canvas-shell {
  flex: 1;
  min-height: 0;
  display: grid;
  place-items: center;
  padding: 18px;
  border: 0;
  border-radius: 0;
  background: var(--bg);
}
body[data-theme="dark"] .canvas-shell {
  background: var(--bg);
}
#previewCanvas {
  width: min(100%, calc(100vh - 210px));
  max-width: 920px;
  aspect-ratio: 1 / 1;
  height: auto;
  display: block;
  border: 0;
  border-radius: 0;
  background: transparent;
}
body[data-theme="dark"] #previewCanvas {
  border-color: transparent;
  background: transparent;
}
.preview-note {
  margin: 12px 4px 0;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.6;
  text-align: center;
}

.control-panel {
  display: flex;
  flex-direction: column;
  min-height: 0;
  padding: 18px;
}
.panel-header {
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}
.panel-header p:last-child {
  margin: 8px 0 0;
  min-height: 20px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.5;
}
.panel-header p.is-error { color: var(--danger); font-weight: 700; }

.theme-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 14px;
}
.theme-row > span {
  color: var(--muted);
  font-size: 13px;
  font-weight: 800;
}
.theme-toggle {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px;
  padding: 4px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--panel-soft);
}
.theme-toggle button {
  min-width: 58px;
  min-height: 32px;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-weight: 800;
}
.theme-toggle button.is-active {
  background: var(--accent);
  color: #ffffff;
  box-shadow: var(--shadow);
}

.selection-summary {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: center;
  margin: 14px 0 0;
  padding: 12px;
  border: 1px solid #bfdbfe;
  border-radius: 12px;
  background: var(--accent-soft);
}
body[data-theme="dark"] .selection-summary {
  border-color: #2f5f95;
}
.selection-summary span {
  display: block;
  margin-bottom: 4px;
  color: #1e40af;
  font-size: 12px;
  font-weight: 800;
}
body[data-theme="dark"] .selection-summary span,
body[data-theme="dark"] .selection-summary p {
  color: #dbeafe;
}
.selection-summary p {
  margin: 0;
  color: #1f3f77;
  font-size: 13px;
  line-height: 1.5;
}
.selection-summary button {
  min-width: 58px;
  min-height: 34px;
  border: 1px solid #93c5fd;
  border-radius: 10px;
  background: #ffffff;
  color: var(--accent-dark);
  cursor: pointer;
  font-weight: 800;
}
body[data-theme="dark"] .selection-summary button {
  border-color: #3b82f6;
  background: #0f172a;
  color: #bfdbfe;
}

.controls {
  overflow: auto;
  display: grid;
  gap: 12px;
  padding: 16px 0;
}
.fixed-notice {
  padding: 12px;
  border: 1px solid #bfdbfe;
  border-radius: 12px;
  background: #eff6ff;
  color: #1e3a8a;
  font-size: 13px;
  line-height: 1.45;
}
body[data-theme="dark"] .fixed-notice {
  border-color: #2f5f95;
  background: #10243a;
  color: #dbeafe;
}
.control-section {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
}
.control-section summary {
  display: grid;
  grid-template-columns: 1fr auto auto;
  gap: 8px;
  align-items: center;
  min-height: 54px;
  padding: 13px 14px;
  cursor: pointer;
  list-style: none;
}
.control-section summary::-webkit-details-marker { display: none; }
.section-title {
  font-weight: 800;
  font-size: 15px;
}
.section-badge {
  padding: 3px 8px;
  border-radius: 999px;
  background: #eef2ff;
  color: #3730a3;
  font-size: 11px;
  font-weight: 800;
}
body[data-theme="dark"] .section-badge {
  background: #1e3a5f;
  color: #bfdbfe;
}
.section-arrow {
  color: var(--accent);
  font-size: 15px;
  font-weight: 900;
}
.control-section[open] .section-arrow { transform: rotate(180deg); }
.section-hint {
  grid-column: 1 / -1;
  color: var(--muted);
  font-size: 12px;
}
.section-body {
  display: grid;
  gap: 0;
  padding: 0 14px 12px;
}
.control-group {
  display: grid;
  grid-template-columns: minmax(120px, 0.46fr) minmax(0, 1fr);
  gap: 12px;
  align-items: center;
  padding: 12px 0;
  border-top: 1px solid #eef2f7;
}
body[data-theme="dark"] .control-group {
  border-top-color: #263449;
}
.control-label {
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
  font-weight: 800;
  font-size: 13px;
}
.color-dot {
  width: 9px;
  height: 9px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1);
}
.control-group select {
  width: 100%;
  height: 40px;
  padding: 0 34px 0 12px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  background-color: #ffffff;
  color: var(--text);
  cursor: pointer;
}
body[data-theme="dark"] .control-group select {
  background-color: #0f172a;
}
.control-group select:focus {
  outline: 2px solid rgba(37, 99, 235, 0.18);
  border-color: var(--accent);
}
.mobile-choice-button {
  display: none;
}

.color-sheet {
  display: none;
}

.actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}
.actions button {
  min-height: 44px;
  border: 1px solid var(--accent);
  border-radius: 10px;
  background: #ffffff;
  color: var(--accent);
  cursor: pointer;
  font-weight: 800;
  transition: transform 0.16s ease, box-shadow 0.16s ease, background 0.16s ease;
}
body[data-theme="dark"] .actions button {
  background: #0f172a;
}
.actions button:hover,
.selection-summary button:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow);
}
.actions button:last-child {
  background: var(--accent);
  color: #ffffff;
}
.actions button:last-child:hover { background: var(--accent-dark); }

@media (max-width: 980px) {
  .announcement-bar { padding: 12px 12px 0; }
  .announcement-inner { grid-template-columns: 1fr; gap: 8px; padding: 12px; }
  .announcement-icon { display: none; }
  .announcement-inner ol { font-size: 13px; line-height: 1.55; }
  .app { grid-template-columns: 1fr; gap: 14px; padding: 12px; }
  .preview-panel, .control-panel { border-radius: 14px; padding: 14px; }
  .preview-header h1, .panel-header h2 { font-size: 22px; }
  .preview-tools { flex-direction: column; align-items: flex-end; gap: 6px; }
  .pin-preview-button { display: inline-flex; align-items: center; justify-content: center; }
  .theme-row { align-items: flex-start; flex-direction: column; }
  .theme-toggle { width: 100%; }
  .canvas-shell { padding: 10px; }
  #previewCanvas { width: min(100%, calc(100vh - 300px)); min-width: 260px; }
  .control-group { grid-template-columns: 1fr; gap: 8px; }
  .control-group select { display: none; }
  .mobile-choice-button {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 10px;
    align-items: center;
    width: 100%;
    min-height: 48px;
    padding: 0 14px;
    border: 1px solid var(--line-strong);
    border-radius: 12px;
    background: var(--panel);
    color: var(--text);
    cursor: pointer;
    text-align: left;
    font-weight: 800;
  }
  .mobile-choice-button span {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .mobile-choice-button b {
    color: var(--accent);
    font-size: 22px;
    line-height: 1;
  }
  body[data-theme="dark"] .mobile-choice-button {
    background: #0f172a;
  }
  .color-sheet {
    position: fixed;
    inset: 0;
    z-index: 80;
    display: grid;
    align-items: end;
    pointer-events: none;
  }
  body.color-sheet-open .color-sheet {
    pointer-events: auto;
  }
  .color-sheet-backdrop {
    position: absolute;
    inset: 0;
    border: 0;
    background: transparent;
  }
  body.color-sheet-open .color-sheet-backdrop {
    background: transparent;
  }
  .color-sheet-panel {
    position: relative;
    z-index: 1;
    max-height: min(52vh, 480px);
    display: flex;
    flex-direction: column;
    border-radius: 22px 22px 0 0;
    border: 1px solid var(--line);
    background: var(--panel);
    box-shadow: 0 -18px 42px rgba(15, 23, 42, 0.24);
    transform: translateY(105%);
    transition: transform 0.2s ease;
  }
  body.color-sheet-open .color-sheet-panel {
    transform: translateY(0);
  }
  .color-sheet-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 12px 16px;
    border-bottom: 1px solid var(--line);
  }
  .color-sheet-kicker {
    display: block;
    margin-bottom: 2px;
    color: var(--accent);
    font-size: 11px;
    font-weight: 900;
    text-transform: uppercase;
  }
  .color-sheet-layer-button {
    min-width: 0;
    flex: 1;
    min-height: 48px;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 2px 10px;
    align-items: center;
    border: 1px solid var(--line-strong);
    border-radius: 14px;
    background: var(--panel-soft);
    color: var(--text);
    cursor: pointer;
    padding: 7px 12px;
    text-align: left;
  }
  .color-sheet-layer-button .color-sheet-kicker {
    grid-column: 1 / -1;
  }
  .color-sheet-layer-button strong {
    min-width: 0;
    overflow: hidden;
    font-size: 17px;
    line-height: 1.2;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .color-sheet-layer-button b {
    font-size: 20px;
    line-height: 1;
  }
  .color-sheet-close {
    width: 36px;
    height: 36px;
    border: 1px solid var(--line);
    border-radius: 50%;
    background: var(--panel-soft);
    color: var(--text);
    cursor: pointer;
    font-size: 24px;
    line-height: 1;
  }
  .color-sheet-options {
    overflow: auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    padding: 12px 16px 16px;
    overscroll-behavior: contain;
    -webkit-overflow-scrolling: touch;
  }
  .color-sheet-options.is-layer-list {
    grid-template-columns: 1fr;
  }
  .color-option-button {
    min-height: 44px;
    padding: 8px 10px;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: var(--panel-soft);
    color: var(--text);
    cursor: pointer;
    font-weight: 800;
    line-height: 1.35;
    text-align: center;
  }
  .color-option-button.is-active {
    border-color: var(--accent);
    background: var(--accent-soft);
    color: var(--accent-dark);
    box-shadow: inset 0 0 0 1px var(--accent);
  }
  body[data-theme="dark"] .color-option-button.is-active {
    color: #dbeafe;
  }
  .layer-option-button {
    text-align: left;
    padding-left: 14px;
  }
  body.preview-pinned.color-sheet-open .color-sheet-panel {
    max-height: min(44vh, 410px);
  }
  body.preview-pinned .announcement-bar {
    display: none;
  }
  body.preview-pinned .app {
    gap: 10px;
  }
  body.preview-pinned .preview-panel {
    position: sticky;
    top: 0;
    z-index: 30;
    margin: -12px -12px 0;
    border-width: 0 0 1px;
    border-radius: 0;
    box-shadow: 0 12px 26px rgba(15, 23, 42, 0.12);
  }
  body.preview-pinned .preview-header {
    align-items: center;
    padding-bottom: 8px;
  }
  body.preview-pinned .preview-header h1 {
    font-size: 18px;
  }
  body.preview-pinned .preview-header .eyebrow,
  body.preview-pinned .preview-note {
    display: none;
  }
  body.preview-pinned .canvas-shell {
    padding: 4px;
  }
  body.preview-pinned #previewCanvas {
    width: min(100%, 42vh);
    min-width: 0;
    max-width: 520px;
  }
}