/* md2mindmap — standalone .md → mindmap page
   A drafting table under a dark instrument rail: the colorful map is the hero,
   the chrome stays quiet and precise. */

:root {
  /* the dark instrument rail — same graphite material as the map's root box */
  --ink: #0F141B;
  --ink-raised: #19212B;
  --ink-line: rgba(233, 240, 247, .10);
  --chrome: #EAF0F7;
  --chrome-soft: #93A0B1;

  /* the light drafting surface */
  --canvas-0: #FFFFFF;
  --canvas-1: #F5F8FB;
  --canvas-2: #E7EEF5;
  --tick: #BFCAD6;

  /* one accent, reserved for the primary action + focus */
  --accent: #5B93FF;
  --accent-deep: #2F6BE0;
  --redline: #C62A2A;

  --mono: ui-monospace, "SF Mono", "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }

/* Visually hidden, still read by search engines and screen readers */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  font: 14px/1.5 var(--sans);
  color: var(--chrome);
  background: var(--ink);
  overflow: hidden;
}

.app {
  display: grid;
  grid-template-rows: auto 1fr;
  height: 100vh;
}

/* ---- Instrument rail ----------------------------------------------------- */
.topbar {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 0 16px;
  height: 54px;
  background:
    linear-gradient(180deg, #131A23 0%, var(--ink) 100%);
  border-bottom: 1px solid #05080C;
  box-shadow: 0 1px 0 var(--ink-line) inset;
  /* The rail-in animation makes this a stacking context for good (fill-mode:
     both keeps the transform applied), so the Export dropdown — which hangs
     below the rail — would otherwise paint underneath .workspace. Lift the
     whole rail above the workspace so the menu is visible. */
  position: relative;
  z-index: 10;
}

/* Wordmark: the `md` file token branches into "mindmap" — the tool's own job. */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  text-decoration: none;
  flex: none;
  -webkit-user-select: none;
  user-select: none;
}
.brand-md {
  font: 600 12.5px/1 var(--mono);
  letter-spacing: .04em;
  color: var(--accent);
  padding: 3px 6px 2px;
  border: 1px solid rgba(91, 147, 255, .45);
  border-radius: 5px;
  background: rgba(91, 147, 255, .08);
}
.brand-arrow { width: 30px; height: 22px; flex: none; overflow: visible; }
.brand-map {
  font: 640 18px/1 var(--sans);
  letter-spacing: -.015em;
  color: var(--chrome);
}

/* Live telemetry about the loaded outline. */
.readout {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-left: 14px;
  margin-left: 2px;
  border-left: 1px solid var(--ink-line);
  font: 500 11px/1 var(--mono);
  letter-spacing: .02em;
  color: var(--chrome-soft);
  white-space: nowrap;
}
.readout b { color: var(--chrome); font-weight: 600; }
.readout .r-open b { color: #FF8B8B; }
.readout .dot { width: 3px; height: 3px; border-radius: 99px; background: var(--chrome-soft); opacity: .5; }
.readout:empty { display: none; }

.spacer { flex: 1; }

/* Control groups */
.group { display: inline-flex; align-items: center; gap: 4px; }
.rule { width: 1px; height: 22px; background: var(--ink-line); margin: 0 6px; flex: none; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  height: 33px;
  padding: 0 12px;
  font: 500 12px/1 var(--mono);
  letter-spacing: .01em;
  color: var(--chrome-soft);
  background: transparent;
  border: 1px solid transparent;
  border-radius: 8px;
  cursor: pointer;
  white-space: nowrap;
  transition: background .14s ease, color .14s ease, border-color .14s ease, transform .05s ease;
}
.btn:hover { background: var(--ink-raised); color: var(--chrome); }
.btn:active { transform: translateY(.5px); }
.btn.icon { width: 33px; padding: 0; font-size: 16px; }
.btn.accent {
  color: #fff;
  background: linear-gradient(180deg, var(--accent) 0%, var(--accent-deep) 100%);
  border-color: var(--accent-deep);
  box-shadow: 0 1px 0 rgba(0,0,0,.25), 0 0 0 0 rgba(91,147,255,.0);
}
.btn.accent:hover { color: #fff; filter: brightness(1.06); }

.topbar input[type="file"] { display: none; }

/* Export dropdown */
.menu { position: relative; display: inline-flex; }
.menu-pop {
  position: absolute;
  top: calc(100% + 6px);
  right: 0;
  z-index: 50;
  min-width: 176px;
  padding: 6px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  background: #141B24;
  border: 1px solid var(--ink-line);
  border-radius: 10px;
  box-shadow: 0 14px 34px rgba(0, 0, 0, .45);
}
.menu-pop[hidden] { display: none; }
.menu-item {
  display: flex;
  align-items: center;
  padding: 8px 10px;
  border: 0;
  border-radius: 7px;
  background: transparent;
  font: 500 12px/1 var(--mono);
  letter-spacing: .01em;
  color: var(--chrome-soft);
  text-align: left;
  white-space: nowrap;
  cursor: pointer;
  transition: background .12s ease, color .12s ease;
}
.menu-item:hover { background: var(--ink-raised); color: var(--chrome); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 8px;
}

/* ---- Workspace split: editor | handle | stage --------------------------- */
.workspace {
  display: grid;
  grid-template-columns: var(--editor-w, 360px) 6px 1fr;
  min-height: 0;
  min-width: 0;
}
.workspace.no-editor { grid-template-columns: 1fr; }
.workspace.no-editor .editor,
.workspace.no-editor .resizer { display: none; }

/* The Markdown editor — a dark writing surface, the material you draft in. */
.editor {
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  background: #0C1118;
  border-right: 1px solid #05080C;
}
.editor-head {
  display: flex;
  align-items: center;
  gap: 8px;
  height: 34px;
  flex: none;
  padding: 0 14px;
  border-bottom: 1px solid var(--ink-line);
  background: linear-gradient(180deg, #10161F 0%, #0C1118 100%);
}
.editor-name {
  font: 600 11px/1 var(--mono);
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--chrome-soft);
}
.editor-stat {
  margin-left: auto;
  font: 500 10.5px/1 var(--mono);
  letter-spacing: .04em;
  color: #586373;
}
.editor-area {
  flex: 1;
  min-height: 0;
  width: 100%;
  resize: none;
  border: 0;
  outline: 0;
  padding: 14px 16px 18px;
  font: 13px/1.7 var(--mono);
  color: #CBD5E1;
  background: transparent;
  tab-size: 2;
  white-space: pre-wrap;
  word-break: break-word;
  overflow: auto;
}
.editor-area::placeholder { color: #3A4453; }
.editor-area::selection { background: rgba(91, 147, 255, .28); }

/* Drag handle between editor and canvas */
.resizer {
  background: var(--ink);
  cursor: col-resize;
  position: relative;
}
.resizer::after {
  content: "";
  position: absolute;
  inset: 0;
  border-left: 1px solid #05080C;
  border-right: 1px solid var(--ink-line);
  transition: background .14s ease;
}
.resizer:hover::after { background: rgba(91, 147, 255, .25); }

/* ---- Stage: the drafting surface ----------------------------------------- */
.stage {
  position: relative;
  overflow: hidden;
  min-width: 0;
  background:
    radial-gradient(120% 90% at 50% 42%, var(--canvas-0) 0%, var(--canvas-1) 62%, var(--canvas-2) 100%);
}
.stage svg { width: 100%; height: 100%; display: block; }

/* Registration ticks — frame the canvas like a plate on a drafting table. */
.corner {
  position: absolute;
  width: 16px; height: 16px;
  border: 0 solid var(--tick);
  pointer-events: none;
  z-index: 3;
  opacity: .8;
}
.corner.tl { top: 14px; left: 14px; border-top-width: 1.5px; border-left-width: 1.5px; }
.corner.tr { top: 14px; right: 14px; border-top-width: 1.5px; border-right-width: 1.5px; }
.corner.bl { bottom: 14px; left: 14px; border-bottom-width: 1.5px; border-left-width: 1.5px; }
.corner.br { bottom: 14px; right: 14px; border-bottom-width: 1.5px; border-right-width: 1.5px; }

/* Drag-and-drop veil */
.drop-veil {
  position: absolute;
  inset: 12px;
  z-index: 4;
  display: none;
  align-items: center;
  justify-content: center;
  border: 2px dashed var(--accent);
  border-radius: 14px;
  background: rgba(91, 147, 255, .07);
  color: var(--accent-deep);
  font: 600 14px/1.4 var(--sans);
  backdrop-filter: blur(1px);
}
.stage.dragging .drop-veil { display: flex; }
.stage.dragging .corner { opacity: 0; }

/* ---- Map nodes (class hooks used by mindmap.js — keep these) -------------- */
.branch { fill: none; stroke-linecap: round; }
/* Cold Steel: graphite root box with white type (matches the workbench app) */
.node-root rect { fill: #12181f; stroke: #0a0e13; stroke-width: 1.5; rx: 10; ry: 10; }
.node-root text { font-size: 18px; font-weight: 700; letter-spacing: .5px; fill: #ffffff; }
.node-topic text { font-size: 15px; font-weight: 600; }
.node-detail text { font-size: 12px; fill: #374151; }
.node-q text { fill: #b91c1c; font-weight: 600; }
.toggle:hover { stroke-width: 2.5; }

/* ---- Empty / error card -------------------------------------------------- */
.empty-hint {
  position: absolute;
  inset: 0;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  color: #5A6675;
  pointer-events: none;
  text-align: center;
  font: 13px/1.6 var(--sans);
}
.empty-hint code {
  font: 12px/1 var(--mono);
  padding: 2px 5px;
  border-radius: 4px;
  background: #E7EEF5;
  color: #2F3A47;
}

/* ---- Load reveal --------------------------------------------------------- */
@media (prefers-reduced-motion: no-preference) {
  .topbar { animation: rail-in .5s cubic-bezier(.2,.7,.2,1) both; }
  .stage svg { animation: map-in .7s cubic-bezier(.2,.7,.2,1) both .08s; }
  @keyframes rail-in { from { opacity: 0; transform: translateY(-8px); } to { opacity: 1; transform: none; } }
  @keyframes map-in { from { opacity: 0; transform: scale(.985); } to { opacity: 1; transform: none; } }
}

/* ---- Responsive ---------------------------------------------------------- */
@media (max-width: 860px) {
  .app { grid-template-rows: auto 1fr; }
  .topbar { height: auto; flex-wrap: wrap; padding: 10px 12px; gap: 8px 10px; }
  .readout { display: none; }
  .spacer { flex-basis: 100%; height: 0; }
  .btn { height: 30px; }
}
@media (max-width: 760px) {
  /* stack: editor on top, map below */
  .workspace { grid-template-columns: 1fr; grid-template-rows: minmax(120px, 40vh) 1fr; }
  .workspace.no-editor { grid-template-rows: 1fr; }
  .resizer { display: none; }
  .editor { border-right: 0; border-bottom: 1px solid #05080C; }
}
@media (max-width: 520px) {
  .brand-map { font-size: 16px; }
  .btn { padding: 0 9px; font-size: 11px; }
  .btn.icon { width: 30px; }
}