:root {
  color-scheme: light;
  --ink: #1b1b1f;
  --muted: #6b6b76;
  --hairline: #e5e5ee;
  --surface: #ffffff;
  --surface-soft: #f6f6f9;
  --canvas: #fff;
  --focus: #6965db;
  --danger: #d1413c;
  --shadow: 0 0 1px rgba(0, 0, 0, 0.17), 0 0 3px rgba(0, 0, 0, 0.08),
    0 7px 14px rgba(0, 0, 0, 0.05);
  --selection: #6965db;
  --selection-soft: #e0dfff;
  --panel: 280px;
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
  margin: 0;
}

body {
  background: #f6f6f9;
  color: var(--ink);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "Noto Sans TC", "Microsoft JhengHei", sans-serif;
  overflow: hidden;
}

button,
input,
textarea {
  font: inherit;
}

button {
  border: 0;
}

.app-shell {
  display: grid;
  grid-template-rows: 56px minmax(0, 1fr);
  height: 100%;
}

.topbar {
  align-items: center;
  background: rgba(255, 255, 255, 0.9);
  border-bottom: 1px solid var(--hairline);
  display: grid;
  gap: 14px;
  grid-template-columns: minmax(230px, 1fr) auto minmax(180px, 1fr);
  padding: 0 14px;
  backdrop-filter: blur(12px);
  z-index: 5;
}

.brand,
.toolbar,
.file-tools {
  align-items: center;
  display: flex;
  min-width: 0;
}

.brand {
  gap: 10px;
}

.brand-copy {
  display: grid;
  gap: 1px;
  min-width: 0;
}

.brand-copy strong {
  font-size: 14px;
  line-height: 18px;
  white-space: nowrap;
}

.brand-copy span {
  color: var(--muted);
  font-size: 12px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.toolbar {
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: 8px;
  box-shadow: var(--shadow);
  gap: 4px;
  justify-self: center;
  padding: 5px;
}

.file-tools {
  gap: 6px;
  justify-content: flex-end;
}

.export-wrap {
  position: relative;
}

.export-menu {
  position: absolute;
  right: 0;
  top: 42px;
  background: #fff;
  border: 1px solid var(--hairline);
  border-radius: 10px;
  box-shadow: var(--shadow);
  display: grid;
  gap: 2px;
  min-width: 160px;
  padding: 6px;
  z-index: 20;
}

.export-menu[hidden] {
  display: none;
}

.export-scope {
  color: var(--muted);
  font-size: 11px;
  padding: 4px 8px 2px;
}

.export-menu button {
  background: transparent;
  border-radius: 7px;
  color: #334155;
  cursor: pointer;
  padding: 8px 10px;
  text-align: left;
}

.export-menu button:hover {
  background: #f1f0ff;
}

.context-menu {
  position: fixed;
  z-index: 50;
  min-width: 188px;
  background: #fff;
  border: 1px solid var(--hairline);
  border-radius: 10px;
  box-shadow: var(--shadow);
  display: grid;
  gap: 2px;
  padding: 6px;
}

.context-menu[hidden] {
  display: none;
}

.context-menu button {
  align-items: center;
  background: transparent;
  border-radius: 7px;
  color: #334155;
  cursor: pointer;
  display: flex;
  gap: 28px;
  justify-content: space-between;
  padding: 8px 10px;
  text-align: left;
  width: 100%;
}

.context-menu button:hover {
  background: #f1f0ff;
}

.context-menu button:disabled {
  color: #cbd5e1;
  cursor: default;
}

.context-menu button:disabled:hover {
  background: transparent;
}

.context-menu button.danger:hover {
  background: #fee2e2;
  color: var(--danger);
}

.context-menu .shortcut {
  color: #9aa3af;
  font-size: 12px;
}

.context-menu .menu-sep {
  background: var(--hairline);
  height: 1px;
  margin: 4px 2px;
}

.lightbox {
  align-items: center;
  background: rgba(15, 23, 42, 0.78);
  cursor: zoom-out;
  display: flex;
  inset: 0;
  justify-content: center;
  padding: 32px;
  position: fixed;
  z-index: 100;
}

.lightbox[hidden] {
  display: none;
}

.lightbox img {
  background: #fff;
  border-radius: 10px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
  max-height: 92vh;
  max-width: 92vw;
}

.rich-toolbar {
  align-items: center;
  background: #fff;
  border: 1px solid var(--hairline);
  border-radius: 8px;
  box-shadow: var(--shadow);
  display: flex;
  gap: 4px;
  padding: 4px;
  position: fixed;
  z-index: 60;
}

.rich-toolbar[hidden] {
  display: none;
}

.rich-toolbar button {
  align-items: center;
  background: transparent;
  border-radius: 6px;
  color: #334155;
  cursor: pointer;
  display: inline-flex;
  height: 28px;
  justify-content: center;
  width: 28px;
}

.rich-toolbar button:hover {
  background: #f1f0ff;
}

.rich-toolbar .rich-color {
  border: 1px solid rgba(15, 23, 42, 0.2);
  height: 20px;
  width: 20px;
}

.rich-toolbar .rich-color::after {
  background: var(--c);
  border-radius: 50%;
  content: "";
  height: 16px;
  width: 16px;
}

.rich-sep {
  background: var(--hairline);
  height: 20px;
  margin: 0 2px;
  width: 1px;
}

.divider {
  background: #d3dce8;
  height: 22px;
  margin: 0 4px;
  width: 1px;
}

.icon-button {
  align-items: center;
  background: transparent;
  border-radius: 7px;
  color: #3d3d3d;
  cursor: pointer;
  display: inline-flex;
  height: 34px;
  justify-content: center;
  padding: 0;
  transition:
    background 120ms ease,
    color 120ms ease,
    transform 120ms ease;
  width: 34px;
}

.icon-button:hover {
  background: #f1f0ff;
}

.icon-button:active {
  transform: translateY(1px);
}

.icon-button:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
}

.icon-button.primary {
  background: var(--selection);
  color: #fff;
}

.icon-button.primary:hover {
  background: #5753d0;
}

.icon-button.danger:hover {
  background: #fee2e2;
  color: var(--danger);
}

.icon-button.small {
  height: 28px;
  width: 28px;
}

.icon-button svg {
  height: 19px;
  width: 19px;
}

.icon-button svg,
.icon-sprite symbol * {
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.zoom-readout {
  color: #475569;
  display: inline-block;
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  min-width: 42px;
  text-align: center;
}

.workspace-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--panel);
  min-height: 0;
}

.inspector {
  background: rgba(255, 255, 255, 0.86);
  min-height: 0;
  overflow: auto;
  padding: 14px;
  z-index: 3;
  border-left: 1px solid var(--hairline);
}

.panel-head {
  align-items: center;
  display: flex;
  justify-content: space-between;
  margin-bottom: 12px;
}

.panel-head h2 {
  font-size: 13px;
  letter-spacing: 0;
  line-height: 18px;
  margin: 0;
}

.canvas-shell {
  display: grid;
  grid-template-rows: minmax(0, 1fr) 30px;
  min-width: 0;
  position: relative;
}

.canvas {
  background:
    radial-gradient(circle at 1px 1px, rgba(122, 122, 122, 0.16) 1px, transparent 0)
      0 0 / 22px 22px,
    linear-gradient(135deg, rgba(224, 223, 255, 0.32), transparent 38%),
    var(--canvas);
  cursor: default;
  min-width: 0;
  overflow: hidden;
  position: relative;
  touch-action: none;
}

/* Plain drag selects; hold Space for the hand/pan tool (Excalidraw convention). */
.canvas.is-space {
  cursor: grab;
}

.canvas.is-panning,
.canvas.is-space.is-panning,
.canvas.is-dragging {
  cursor: grabbing;
}

.marquee {
  position: absolute;
  border: 1.5px solid var(--selection);
  background: rgba(105, 101, 219, 0.1);
  border-radius: 2px;
  pointer-events: none;
  z-index: 4;
}

.marquee[hidden] {
  display: none;
}

.drop-indicator {
  background: var(--selection);
  border-radius: 2px;
  box-shadow: 0 0 0 2px rgba(105, 101, 219, 0.22);
  left: 0;
  pointer-events: none;
  position: absolute;
  top: 0;
  z-index: 5;
}

.drop-indicator[hidden] {
  display: none;
}

.search-bar {
  align-items: center;
  background: #fff;
  border: 1px solid var(--hairline);
  border-radius: 10px;
  box-shadow: var(--shadow);
  display: flex;
  gap: 6px;
  left: 50%;
  padding: 6px 8px;
  position: absolute;
  top: 12px;
  transform: translateX(-50%);
  z-index: 20;
}

.search-bar[hidden] {
  display: none;
}

.search-icon {
  fill: none;
  height: 16px;
  stroke: #64748b;
  stroke-linecap: round;
  stroke-width: 1.8;
  width: 16px;
}

#searchInput {
  background: transparent;
  border: 0;
  color: var(--ink);
  outline: none;
  padding: 4px 2px;
  width: 180px;
}

.search-count {
  color: var(--muted);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  min-width: 34px;
  text-align: center;
}

.search-bar button[data-search] {
  align-items: center;
  background: transparent;
  border-radius: 6px;
  color: #475569;
  cursor: pointer;
  display: inline-flex;
  height: 26px;
  justify-content: center;
  width: 26px;
}

.search-bar button[data-search]:hover {
  background: #f1f0ff;
}

.topic.is-search-match .topic-sketch {
  filter: drop-shadow(0 0 3px #f59e0b) drop-shadow(0 0 2px #f59e0b);
}

.topic.is-search-active .topic-sketch {
  filter: drop-shadow(0 0 6px #f97316) drop-shadow(0 0 4px #f97316);
}

.canvas:focus {
  outline: none;
}

.world {
  height: 1px;
  left: 0;
  position: absolute;
  top: 0;
  transform-origin: 0 0;
  width: 1px;
  will-change: transform;
}

.link-layer {
  height: 1px;
  left: 0;
  overflow: visible;
  pointer-events: none;
  position: absolute;
  top: 0;
  width: 1px;
}

/* rough.js sets stroke colour, width and dash as attributes; CSS only rounds caps. */
.link-layer path {
  stroke-linecap: round;
  stroke-linejoin: round;
}

.rough-link {
  fill: none;
  opacity: 0.92;
}

.boundary-path {
  pointer-events: none;
}

.relationship-link,
.relationship-arrow {
  fill: none;
}

.topic-layer {
  height: 1px;
  left: 0;
  position: absolute;
  top: 0;
  width: 1px;
}

.topic {
  align-items: center;
  color: #0f172a;
  cursor: default;
  display: flex;
  flex-direction: column;
  gap: 4px;
  justify-content: center;
  padding: 9px 16px;
  position: absolute;
  user-select: none;
  will-change: transform;
}

.topic.is-draggable {
  cursor: grab;
}

.topic.is-selected {
  z-index: 2;
}

.topic.is-editing {
  cursor: text;
  user-select: text;
  z-index: 4;
}

.topic.is-relationship-source {
  filter: drop-shadow(0 0 5px rgba(105, 101, 219, 0.55));
}

.topic-sketch {
  height: 100%;
  left: 0;
  overflow: visible;
  pointer-events: none;
  position: absolute;
  top: 0;
  width: 100%;
  /* Gentle lift off the grid; the shadow follows the hand-drawn outline. */
  filter: drop-shadow(0 2px 2px rgba(15, 23, 42, 0.07));
}

.topic-sketch path {
  stroke-linecap: round;
  stroke-linejoin: round;
}

.topic-text {
  display: block;
  line-height: 1.28;
  max-width: 100%;
  outline: none;
  overflow-wrap: anywhere;
  position: relative;
  text-align: center;
  white-space: pre-wrap;
  z-index: 1;
}

.topic-marker {
  align-items: center;
  background: var(--selection);
  border: 2px solid #fff;
  border-radius: 999px;
  color: #fff;
  display: flex;
  font-size: 10px;
  font-weight: 800;
  height: 22px;
  justify-content: center;
  line-height: 1;
  min-width: 22px;
  padding: 0 5px;
  position: absolute;
  right: -9px;
  top: -10px;
  z-index: 3;
}

.topic-marker[hidden] {
  display: none;
}

.topic-link,
.topic-note {
  align-items: center;
  background: #fff;
  border: 1.5px solid var(--selection);
  border-radius: 999px;
  color: var(--selection);
  display: flex;
  height: 22px;
  justify-content: center;
  position: absolute;
  width: 22px;
  z-index: 3;
}

.topic-link {
  cursor: pointer;
  left: -9px;
  top: -10px;
}

.topic-link:hover {
  background: var(--selection);
  color: #fff;
}

.topic-note {
  border-color: #94a3b8;
  bottom: -10px;
  color: #64748b;
  left: -9px;
  pointer-events: none;
}

.topic-link svg,
.topic-note svg {
  fill: none;
  height: 13px;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.9;
  width: 13px;
}

.topic-link[hidden],
.topic-note[hidden] {
  display: none;
}

.topic-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  justify-content: center;
  max-width: 100%;
  position: relative;
  z-index: 1;
}

.topic-tags[hidden] {
  display: none;
}

.topic-tag {
  background: rgba(15, 23, 42, 0.07);
  border-radius: 999px;
  color: #475569;
  font-size: 11px;
  line-height: 1.5;
  padding: 0 8px;
  white-space: nowrap;
}

.topic-image {
  position: relative;
  width: 100%;
  z-index: 1;
}

.topic-image[hidden] {
  display: none;
}

.topic-image img {
  border-radius: 6px;
  cursor: zoom-in;
  display: block;
  object-fit: contain;
  width: 100%;
}

.topic[data-marker="done"] .topic-marker {
  background: #2b8a3e;
}

.topic[data-marker="star"] .topic-marker {
  background: #ec8b14;
}

.topic[data-marker="progress-half"] .topic-marker {
  background: #1971c2;
  font-size: 9px;
}

.topic[data-shape="underline"] .topic-text {
  /* No filled box behind underline topics, so keep text legible on the grid. */
  text-shadow: 0 0 4px #fff, 0 0 4px #fff, 0 0 4px #fff;
}

.topic.is-root .topic-sketch {
  filter: drop-shadow(0 6px 14px rgba(105, 101, 219, 0.16));
}

.topic.is-selected::after {
  border: 1.5px solid var(--selection);
  border-radius: calc(var(--topic-radius) + 5px);
  bottom: -7px;
  content: "";
  left: -7px;
  pointer-events: none;
  position: absolute;
  right: -7px;
  top: -7px;
}

.topic.is-selected::before {
  background: #fff;
  border: 1.5px solid var(--selection);
  border-radius: 50%;
  bottom: -11px;
  box-shadow:
    calc(100% + 12px) 0 0 -1.5px #fff,
    calc(100% + 12px) 0 0 0 var(--selection),
    0 calc(-100% - 12px) 0 -1.5px #fff,
    0 calc(-100% - 12px) 0 0 var(--selection),
    calc(100% + 12px) calc(-100% - 12px) 0 -1.5px #fff,
    calc(100% + 12px) calc(-100% - 12px) 0 0 var(--selection);
  content: "";
  height: 7px;
  left: -11px;
  pointer-events: none;
  position: absolute;
  width: 7px;
  z-index: 3;
}

.topic.is-drop-target {
  z-index: 3;
}

.topic.is-drop-target::after {
  border: 2px dashed var(--selection);
  border-radius: calc(var(--topic-radius) + 7px);
  bottom: -10px;
  content: "";
  left: -10px;
  pointer-events: none;
  position: absolute;
  right: -10px;
  top: -10px;
}

.collapse-badge {
  align-items: center;
  background: #fff;
  border: 1px solid #cbd5e1;
  border-radius: 999px;
  bottom: -9px;
  color: #334155;
  display: flex;
  font-size: 10px;
  height: 18px;
  justify-content: center;
  min-width: 18px;
  padding: 0 5px;
  position: absolute;
  right: -8px;
  z-index: 3;
}

.canvas-status {
  align-items: center;
  background: rgba(255, 255, 255, 0.86);
  border-top: 1px solid var(--hairline);
  color: var(--muted);
  display: flex;
  font-size: 12px;
  justify-content: space-between;
  min-width: 0;
  padding: 0 12px;
}

.field,
.control-group {
  display: grid;
  gap: 8px;
  margin-bottom: 16px;
}

.field span,
.control-label,
.toggle-field span {
  color: #475569;
  font-size: 12px;
  font-weight: 650;
  line-height: 16px;
}

.field input[type="text"],
.field textarea {
  background: #fff;
  border: 1px solid #cbd5e1;
  border-radius: 7px;
  color: var(--ink);
  min-width: 0;
  padding: 9px 10px;
  resize: vertical;
  width: 100%;
}

.field input[type="text"]:focus,
.field textarea:focus {
  border-color: #2563eb;
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
  outline: none;
}

.field.compact {
  gap: 10px;
}

.field input[type="range"] {
  accent-color: #2563eb;
  width: 100%;
}

.swatches {
  display: grid;
  gap: 8px;
  grid-template-columns: repeat(6, 1fr);
}

.swatch {
  aspect-ratio: 1;
  background: var(--swatch);
  border: 1px solid rgba(15, 23, 42, 0.16);
  border-radius: 50%;
  cursor: pointer;
  padding: 0;
  position: relative;
}

.swatch.is-active::after {
  border: 2px solid #1d4ed8;
  border-radius: inherit;
  bottom: -4px;
  content: "";
  left: -4px;
  position: absolute;
  right: -4px;
  top: -4px;
}

.theme-swatches {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.theme-swatch {
  border: 1px solid rgba(15, 23, 42, 0.18);
  border-radius: 7px;
  cursor: pointer;
  height: 28px;
  padding: 0;
  position: relative;
  width: 38px;
}

.theme-swatch.is-active {
  outline: 2px solid var(--selection);
  outline-offset: 2px;
}

.segmented {
  background: #eef2f7;
  border: 1px solid #dbe3ef;
  border-radius: 8px;
  display: grid;
  gap: 3px;
  grid-auto-columns: minmax(0, 1fr);
  grid-auto-flow: column;
  padding: 3px;
}

.segmented button {
  background: transparent;
  border-radius: 6px;
  color: #475569;
  cursor: pointer;
  min-height: 30px;
  padding: 4px 8px;
}

.segmented button.is-active {
  background: #fff;
  box-shadow: 0 1px 4px rgba(15, 23, 42, 0.12);
  color: #0f172a;
}

.segmented.marker-control {
  grid-auto-flow: row;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.marker-control button {
  font-size: 12px;
  font-weight: 750;
}

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

.textstyle-row .segmented {
  flex: 1;
}

#textColorInput {
  background: #fff;
  border: 1px solid #cbd5e1;
  border-radius: 7px;
  cursor: pointer;
  height: 34px;
  padding: 2px;
  width: 44px;
}

.image-row {
  display: flex;
  gap: 8px;
}

.image-row button {
  background: #fff;
  border: 1px solid #cbd5e1;
  border-radius: 7px;
  color: #334155;
  cursor: pointer;
  flex: 1;
  padding: 8px 10px;
}

.image-row button:hover {
  background: #f1f0ff;
}

.image-row button:disabled {
  color: #cbd5e1;
  cursor: default;
}

.image-row button:disabled:hover {
  background: #fff;
}

.toggle-field {
  align-items: center;
  display: grid;
  gap: 10px;
  grid-template-columns: minmax(0, 1fr) 42px;
  margin-bottom: 16px;
}

.toggle-field input {
  opacity: 0;
  pointer-events: none;
  position: absolute;
}

.toggle-field i {
  background: #d6d6d6;
  border-radius: 999px;
  cursor: pointer;
  height: 24px;
  position: relative;
  transition: background 120ms ease;
  width: 42px;
}

.toggle-field i::after {
  background: #fff;
  border-radius: 50%;
  box-shadow: 0 1px 4px rgba(15, 23, 42, 0.22);
  content: "";
  height: 18px;
  left: 3px;
  position: absolute;
  top: 3px;
  transition: transform 120ms ease;
  width: 18px;
}

.toggle-field input:checked + i {
  background: var(--selection);
}

.toggle-field input:checked + i::after {
  transform: translateX(18px);
}

.notes-field textarea {
  min-height: 118px;
}

.icon-sprite {
  display: none;
}

@media (max-width: 1100px) {
  :root {
    --panel: 236px;
  }

  .topbar {
    grid-template-columns: 1fr auto auto;
  }
}

@media (max-width: 860px) {
  body {
    overflow: auto;
  }

  .app-shell {
    min-height: 100dvh;
  }

  .topbar {
    grid-template-columns: 1fr;
    height: auto;
    padding: 10px;
  }

  .toolbar,
  .file-tools {
    justify-self: start;
  }

  .workspace-layout {
    grid-template-columns: 1fr;
    grid-template-rows: minmax(460px, 1fr) auto;
  }

  .canvas-shell {
    min-height: 460px;
    order: 1;
  }

  .inspector {
    border: 0;
    max-height: none;
    order: 2;
    border-top: 1px solid var(--hairline);
  }
}