:root {
  --bg: #f4f6f9;
  --panel: #ffffff;
  --panel-2: #f8fafc;
  --border: #d4dae3;
  --border-strong: #9aa4b2;
  --ink: #1f2733;
  --ink-soft: #4a5567;
  --accent: #2563eb;
  --accent-soft: #dbeafe;
  --danger: #dc2626;
  --warn: #f59e0b;
  --shadow: 0 1px 2px rgba(15,23,42,.06), 0 4px 12px rgba(15,23,42,.06);
  --mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 13px;
  color: var(--ink);
  background: var(--bg);
  overflow: hidden;
}

#app {
  display: grid;
  grid-template-columns: 1fr;
  grid-template-rows: 48px 1fr;
  grid-template-areas:
    "toolbar"
    "canvas";
  height: 100vh;
}

/* Toolbar ------------------------------------------------------------ */
#toolbar {
  grid-area: toolbar;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 0 12px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow);
  z-index: 10;
}

.tb-group {
  display: flex;
  align-items: center;
  gap: 2px;
  padding-right: 8px;
  margin-right: 8px;
  border-right: 1px solid var(--border);
}
.tb-group:last-child { border-right: none; }

.tb-btn {
  appearance: none;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 6px;
  padding: 6px 10px;
  font-size: 13px;
  color: var(--ink);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
}
.tb-btn:hover { background: var(--panel-2); border-color: var(--border); }
.tb-btn.active {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}
.tb-btn .kbd {
  font-family: var(--mono);
  font-size: 10px;
  color: var(--ink-soft);
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 1px 4px;
}
.tb-title {
  font-weight: 700;
  font-size: 14px;
  letter-spacing: .02em;
  margin-right: 8px;
  color: var(--ink);
}
.tb-title span { color: var(--accent); }
.tb-title .tb-version {
  color: var(--ink-soft);
  font-weight: 500;
  font-size: 11px;
  letter-spacing: 0;
  margin-left: 6px;
  font-family: var(--mono);
}
.tb-paper {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  color: var(--ink-soft);
  margin-left: 4px;
}
.tb-select {
  font-size: 12px;
  padding: 3px 6px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--panel);
  color: var(--ink);
  cursor: pointer;
}
.tb-select:hover { border-color: var(--border-strong); }
.tb-spacer { flex: 1; }

/* Canvas ------------------------------------------------------------- */
#canvas-wrap {
  grid-area: canvas;
  position: relative;
  overflow: hidden;
  background:
    linear-gradient(0deg, rgba(0,0,0,.02), rgba(0,0,0,.02)),
    var(--bg);
}
#canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  touch-action: none;
  /* Suppress native text selection so dragging a node (esp. a small split)
     doesn't sweep over connector labels / cavity text and highlight them. */
  user-select: none;
  -webkit-user-select: none;
}
#canvas.tool-select   { cursor: default; }
#canvas.tool-pan      { cursor: grab; }
#canvas.tool-pan.dragging { cursor: grabbing; }
#canvas.tool-add-connector { cursor: crosshair; }
#canvas.tool-add-bundle    { cursor: crosshair; }
#canvas.tool-add-split     { cursor: crosshair; }

#cell-editor-host {
  position: absolute;
  inset: 0;
  pointer-events: none;
}
#cell-editor-host input {
  position: absolute;
  pointer-events: auto;
  border: 2px solid var(--accent);
  background: #fff;
  font-family: system-ui, sans-serif;
  font-size: 12px;
  padding: 1px 4px;
  outline: none;
  box-shadow: 0 0 0 4px var(--accent-soft);
  border-radius: 2px;
}

#status-bar {
  position: absolute;
  left: 8px;
  bottom: 8px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 4px 10px;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-soft);
  box-shadow: var(--shadow);
  pointer-events: none;
}

/* Modal -------------------------------------------------------------- */
#modal-host {
  position: fixed;
  inset: 0;
  background: rgba(15,23,42,.45);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
}
#modal-host[hidden] { display: none; }
.modal {
  background: var(--panel);
  border-radius: 10px;
  box-shadow: 0 10px 40px rgba(0,0,0,.25);
  min-width: 360px;
  max-width: 92vw;
  max-height: 88vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.modal header {
  padding: 12px 16px;
  font-weight: 600;
  border-bottom: 1px solid var(--border);
  background: var(--panel-2);
}
.modal .body {
  padding: 16px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.modal footer {
  padding: 10px 16px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  background: var(--panel-2);
}
.field {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.field label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--ink-soft);
}
.field input,
.field select,
.field textarea {
  font: inherit;
  padding: 6px 8px;
  border: 1px solid var(--border);
  border-radius: 5px;
  background: #fff;
  color: var(--ink);
}
.field input:focus,
.field select:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.row {
  display: flex;
  gap: 10px;
}
.row > .field { flex: 1; }

/* Right-click context menu. Appended to body, positioned with inline
   left/top; the module clips to the viewport on open. */
.context-menu {
  position: fixed;
  min-width: 180px;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 6px;
  box-shadow: 0 8px 24px rgba(0,0,0,.18);
  padding: 4px 0;
  z-index: 100;
  font-size: 13px;
  user-select: none;
}
.cm-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  text-align: left;
  padding: 6px 14px;
  background: transparent;
  border: none;
  font: inherit;
  cursor: pointer;
  color: var(--ink);
}
.cm-item:hover:not(:disabled) { background: var(--accent-soft); color: var(--accent); }
.cm-item:disabled { color: var(--border-strong); cursor: default; }
.cm-item.danger { color: var(--danger); }
.cm-item.danger:hover:not(:disabled) { background: #fee2e2; color: var(--danger); }
.cm-shortcut {
  color: var(--ink-soft);
  font-size: 11px;
  font-family: var(--mono);
  margin-left: 24px;
}
.cm-item.danger .cm-shortcut { color: var(--danger); opacity: .7; }
.cm-item:hover:not(:disabled) .cm-shortcut { color: var(--accent); }
.cm-separator {
  height: 1px;
  background: var(--border);
  margin: 4px 0;
}

/* Color field with live swatch (used by the bundle editor) */
.color-row {
  display: flex;
  align-items: center;
  gap: 8px;
}
.color-row input { flex: 1; }
.color-swatch {
  width: 26px;
  height: 26px;
  border: 1px solid var(--border-strong);
  border-radius: 4px;
  flex-shrink: 0;
  background: transparent;
}

.btn {
  appearance: none;
  background: var(--panel);
  color: var(--ink);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 6px 14px;
  font: inherit;
  cursor: pointer;
}
.btn:hover { border-color: var(--border-strong); }
.btn.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.btn.primary:hover { background: #1d4ed8; border-color: #1d4ed8; }
.btn.danger {
  background: #fff;
  border-color: var(--danger);
  color: var(--danger);
}

/* Connector library modal — folder tree + template rows. */
.lib-toolbar {
  display: flex;
  gap: 6px;
  padding: 4px 0 12px 0;
  border-bottom: 1px solid var(--border);
  margin-bottom: 8px;
}
.lib-empty {
  padding: 24px 8px;
  font-size: 13px;
  color: var(--ink-soft);
  line-height: 1.5;
}
.lib-empty p { margin: 0 0 8px 0; }
.lib-tree { font-size: 13px; }
.lib-folder {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 4px;
  cursor: default;
  border-radius: 4px;
}
.lib-folder:hover { background: var(--panel-2); }
.lib-caret {
  display: inline-block;
  width: 14px;
  text-align: center;
  color: var(--ink-soft);
  cursor: pointer;
  user-select: none;
}
.lib-folder-name {
  flex: 1;
  font-weight: 600;
  cursor: pointer;
  user-select: none;
}
.lib-folder-note {
  font-size: 11px;
  font-style: italic;
  color: var(--ink-soft);
  margin-right: 6px;
}
.lib-folder-children {
  margin-left: 22px;
  padding-left: 6px;
  border-left: 1px dashed var(--border);
}
.lib-template {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 5px 4px;
  border-radius: 4px;
}
.lib-template:hover { background: var(--panel-2); }
.lib-template-main { font-weight: 500; }
.lib-template-meta {
  flex: 1;
  font-size: 11px;
  color: var(--ink-soft);
  font-family: var(--mono);
}
.lib-insert {
  padding: 2px 10px;
  font-size: 12px;
}
.lib-del {
  appearance: none;
  background: transparent;
  border: none;
  color: var(--ink-soft);
  cursor: pointer;
  font-size: 16px;
  padding: 0 6px;
  border-radius: 3px;
  line-height: 1;
}
.lib-del:hover { color: var(--danger); background: #fee2e2; }
.lib-actions {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  margin-left: auto;
}
.lib-action {
  appearance: none;
  background: transparent;
  border: none;
  color: var(--ink-soft);
  cursor: pointer;
  font-size: 13px;
  padding: 2px 6px;
  border-radius: 3px;
  line-height: 1;
}
.lib-action:hover { background: var(--panel-2); color: var(--ink); }
.lib-toolbar-check {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  color: var(--ink-soft);
  margin-left: 2px;
  margin-right: auto;
  user-select: none;
  cursor: pointer;
}
.lib-toolbar-check input { margin: 0; }
.lib-edit-row { background: var(--panel-2); }
.lib-rename-input {
  flex: 1;
  font-size: 13px;
  padding: 2px 4px;
  border: 1px solid var(--accent);
  border-radius: 3px;
  background: var(--panel);
  color: var(--ink);
  font-family: inherit;
}
.lib-move-label {
  font-size: 13px;
  color: var(--ink);
}
.lib-move-select {
  flex: 1;
  font-size: 12px;
  padding: 2px 4px;
}

/* Bundle editor — Carries panel (read-only list of wires through the bundle) */
.carries-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12px;
}
.carries-table th, .carries-table td {
  border: 1px solid var(--border);
  padding: 4px 6px;
  text-align: left;
}
.carries-table th { background: var(--panel-2); font-weight: 600; }
.carries-table tbody tr:nth-child(even) { background: var(--panel-2); }

/* Title block editor */
.tb-editor table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12px;
}
.tb-editor th, .tb-editor td {
  border: 1px solid var(--border);
  padding: 4px 6px;
  text-align: left;
}
.tb-editor th { background: var(--panel-2); font-weight: 600; }
.tb-editor input {
  width: 100%;
  border: none;
  background: transparent;
  font: inherit;
  padding: 0;
  outline: none;
}
.tb-editor input:focus { background: var(--accent-soft); }
.tb-editor .row-actions { width: 36px; text-align: center; }
.tb-editor .row-actions button {
  background: none;
  border: none;
  color: var(--danger);
  cursor: pointer;
  font-size: 14px;
  padding: 0;
}

/* Print / PDF export ------------------------------------------------- */
/* src/export/print.js injects a .rh-print-sheet into <body> before calling
   window.print(). On screen it stays hidden; the @media print block below
   swaps visibility so only the drawing reaches the paper / PDF. */
.rh-print-sheet { display: none; }

@media print {
  html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    background: #ffffff;
    overflow: visible;
  }
  body > *:not(.rh-print-sheet) { display: none !important; }
  .rh-print-sheet {
    display: block !important;
    width: 100%;
    height: 100%;
  }
  .rh-print-sheet svg {
    width: 100%;
    height: 100%;
    display: block;
  }
}