:root {
  --paper: #f2f5ff;
  --paper-solid: #f7f8ff;
  --ink: #181b30;
  --muted: #69708c;
  --line: #cdd3e7;
  --grid-major: rgba(67, 83, 255, 0.12);
  --grid-minor: rgba(31, 41, 85, 0.055);
  --cobalt: #4353ff;
  --cobalt-soft: #e7eaff;
  --cyan: #008eaa;
  --cyan-soft: #dff7fb;
  --amber: #b96b00;
  --amber-soft: #fff0cf;
  --magenta: #c1387b;
  --magenta-soft: #ffe2f0;
  --green: #347c55;
  --green-soft: #e4f4e9;
  --white: #ffffff;
  --shadow: 0 18px 50px rgba(34, 40, 79, 0.13);
  font-family: Aptos, "Segoe UI Variable", "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
}

* { box-sizing: border-box; }

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

button, input, textarea, select { font: inherit; }
button { color: inherit; }

button:focus-visible, input:focus-visible, textarea:focus-visible, select:focus-visible, [tabindex]:focus-visible {
  outline: 3px solid rgba(67, 83, 255, 0.32);
  outline-offset: 2px;
}

.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;
}

.skip-link {
  position: fixed;
  z-index: 200;
  top: 8px;
  left: 112px;
  transform: translateY(-70px);
  border-radius: 3px;
  padding: 9px 12px;
  color: var(--white);
  background: var(--ink);
  font-size: 13px;
}
.skip-link:focus { transform: translateY(0); }

.app-shell {
  display: grid;
  grid-template-columns: 104px minmax(0, 1fr) 290px;
  grid-template-rows: 68px minmax(0, 1fr);
  width: 100vw;
  height: 100dvh;
  background: var(--paper);
}

.masthead {
  position: relative;
  z-index: 30;
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: 104px minmax(180px, 1fr) auto auto;
  align-items: center;
  gap: 18px;
  min-width: 0;
  height: 68px;
  border-bottom: 1px solid var(--line);
  background: rgba(247, 248, 255, 0.92);
  backdrop-filter: blur(14px);
}

.identity {
  align-self: stretch;
  display: flex;
  align-items: center;
  gap: 9px;
  padding-left: 14px;
  color: var(--white);
  background: var(--ink);
}

.identity-mark {
  display: grid;
  place-items: center;
  width: 31px;
  height: 31px;
  border: 1px solid rgba(255, 255, 255, 0.54);
  font: 700 10px/1 "Cascadia Code", Consolas, monospace;
  letter-spacing: -1px;
}

.identity-name {
  font: 650 8px/1.08 Bahnschrift, "Arial Narrow", sans-serif;
  letter-spacing: 0.13em;
}

.canvas-title-wrap { min-width: 0; }
.canvas-title {
  width: min(100%, 620px);
  border: 0;
  border-bottom: 1px solid transparent;
  padding: 6px 3px 5px;
  color: var(--ink);
  background: transparent;
  font: 500 clamp(19px, 2vw, 27px)/1.1 Bahnschrift, "Arial Narrow", sans-serif;
  letter-spacing: -0.025em;
}
.canvas-title:hover { border-bottom-color: var(--line); }
.canvas-title:focus { border-bottom-color: var(--cobalt); }

.sync-state {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font: 600 10px/1 "Cascadia Code", Consolas, monospace;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.sync-pulse {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #4fab78;
  box-shadow: 0 0 0 4px rgba(79, 171, 120, 0.14);
}
.sync-state.is-busy .sync-pulse { background: var(--amber); }
.sync-state.is-error .sync-pulse { background: #d64c4c; }

.top-action {
  height: 38px;
  margin-right: 16px;
  border: 1px solid var(--line);
  border-radius: 3px;
  padding: 0 13px;
  background: var(--white);
  cursor: pointer;
  font-size: 13px;
}
.top-action:hover { border-color: var(--cobalt); color: var(--cobalt); }

.tool-rail {
  z-index: 20;
  grid-column: 1;
  grid-row: 2;
  overflow-y: auto;
  border-right: 1px solid var(--line);
  padding: 12px 9px 18px;
  background: var(--paper-solid);
  scrollbar-width: none;
}

.tool-cluster { display: grid; gap: 6px; }
.node-tools { padding-bottom: 12px; }

.tool-button {
  position: relative;
  display: grid;
  grid-template-columns: 28px 1fr;
  align-items: center;
  width: 100%;
  min-height: 43px;
  border: 1px solid transparent;
  border-radius: 4px;
  padding: 5px 5px;
  background: transparent;
  cursor: pointer;
  text-align: left;
}
.tool-button > span {
  display: grid;
  place-items: center;
  width: 26px;
  height: 26px;
  border: 1px solid var(--line);
  border-radius: 3px;
  background: var(--white);
  font: 700 15px/1 Bahnschrift, sans-serif;
}
.tool-button small { font-size: 10px; color: var(--muted); overflow: hidden; }
.tool-button:hover { background: #ebeefe; }
.tool-button.is-active { border-color: var(--cobalt); background: var(--cobalt-soft); color: var(--cobalt); }
.tool-button.is-active small { color: var(--cobalt); }
.kind-question > span { color: var(--cobalt); background: var(--cobalt-soft); }
.kind-hypothesis > span { color: var(--amber); background: var(--amber-soft); }
.kind-component > span { color: var(--cyan); background: var(--cyan-soft); }
.kind-decision > span { color: var(--magenta); background: var(--magenta-soft); }
.kind-note > span { color: var(--ink); }
.kind-frame > span { color: var(--green); background: var(--green-soft); }

.rail-rule {
  display: flex;
  align-items: center;
  gap: 5px;
  margin: 16px 1px 9px;
  color: var(--muted);
  font: 600 7px/1 "Cascadia Code", Consolas, monospace;
  letter-spacing: 0.08em;
}
.rail-rule::after { content: ""; flex: 1; height: 1px; background: var(--line); }

.canvas-region { position: relative; grid-column: 2; grid-row: 2; min-width: 0; min-height: 0; }
.viewport {
  position: absolute;
  inset: 0;
  overflow: hidden;
  touch-action: none;
  cursor: grab;
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid-major) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-major) 1px, transparent 1px),
    linear-gradient(var(--grid-minor) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-minor) 1px, transparent 1px);
  background-size: 100px 100px, 100px 100px, 20px 20px, 20px 20px;
}
.viewport.is-placement { cursor: crosshair; }
.viewport.is-panning { cursor: grabbing; }
.viewport.is-linking { cursor: alias; }

.world {
  position: absolute;
  left: 0;
  top: 0;
  width: 6000px;
  height: 4000px;
  transform-origin: 0 0;
  will-change: transform;
}
.edge-layer, .stroke-layer, .node-layer { position: absolute; inset: 0; width: 6000px; height: 4000px; overflow: visible; }
.edge-layer { z-index: 2; pointer-events: none; }
.stroke-layer { z-index: 3; pointer-events: none; }
.node-layer { z-index: 4; pointer-events: none; }

.relation-line {
  fill: none;
  stroke: #7b84a5;
  stroke-width: 2;
  marker-end: url(#arrowhead);
  vector-effect: non-scaling-stroke;
}
.relation-hit {
  fill: none;
  stroke: transparent;
  stroke-width: 18;
  pointer-events: stroke;
  cursor: pointer;
}
.relation.is-selected .relation-line { stroke: var(--cobalt); stroke-width: 3; }
.relation.is-pending .relation-line { stroke: var(--cobalt); stroke-dasharray: 8 6; }
.relation-label-bg { fill: rgba(247, 248, 255, 0.96); stroke: var(--line); rx: 3; }
.relation-label {
  fill: #535b79;
  font: 600 10px "Cascadia Code", Consolas, monospace;
  letter-spacing: 0.02em;
  text-anchor: middle;
  dominant-baseline: central;
  pointer-events: none;
}

.stroke-path { fill: none; stroke-linecap: round; stroke-linejoin: round; vector-effect: non-scaling-stroke; }

.thought-node {
  position: absolute;
  z-index: 2;
  display: flex;
  flex-direction: column;
  min-width: 180px;
  min-height: 110px;
  border: 1px solid var(--line);
  border-top: 4px solid var(--node-color, var(--ink));
  border-radius: 5px;
  padding: 14px 16px 15px;
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 7px 18px rgba(34, 40, 79, 0.09);
  pointer-events: auto;
  user-select: none;
  cursor: grab;
}
.thought-node:hover { box-shadow: 0 12px 26px rgba(34, 40, 79, 0.14); }
.thought-node.is-selected {
  border-color: var(--cobalt);
  border-top-color: var(--node-color, var(--cobalt));
  box-shadow: 0 0 0 3px rgba(67, 83, 255, 0.16), var(--shadow);
}
.thought-node.is-link-source { box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.25), var(--shadow); }
.thought-node[data-kind="question"] { --node-color: var(--cobalt); background: #fafaff; }
.thought-node[data-kind="hypothesis"] { --node-color: #df8b13; background: #fffdf7; }
.thought-node[data-kind="component"] { --node-color: #00a2bd; background: #f8feff; }
.thought-node[data-kind="decision"] { --node-color: var(--magenta); background: #fffafd; }
.thought-node[data-kind="note"] { --node-color: #616a87; }
.thought-node[data-kind="frame"] {
  z-index: 1;
  border: 2px dashed #83a48f;
  border-top: 2px solid #4f8a64;
  background: rgba(230, 245, 235, 0.24);
  box-shadow: none;
}

.node-meta { display: flex; align-items: center; gap: 8px; min-height: 17px; }
.node-kind {
  color: var(--node-color, var(--muted));
  font: 700 9px/1 "Cascadia Code", Consolas, monospace;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}
.node-status {
  margin-left: auto;
  color: var(--muted);
  font: 600 9px/1 "Cascadia Code", Consolas, monospace;
}
.node-title {
  margin: 13px 0 7px;
  max-width: 100%;
  font: 600 18px/1.16 Bahnschrift, "Arial Narrow", sans-serif;
  letter-spacing: -0.015em;
  overflow-wrap: anywhere;
  text-wrap: balance;
}
.node-body {
  margin: 0;
  color: #5e6682;
  font-size: 12.5px;
  line-height: 1.42;
  overflow: hidden;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}
.node-tags { display: flex; flex-wrap: wrap; gap: 4px; margin-top: auto; padding-top: 10px; }
.node-tag { border: 1px solid var(--line); padding: 2px 5px; font-size: 9px; color: var(--muted); background: var(--paper-solid); }

.origin-label {
  position: absolute;
  z-index: 1;
  left: 8px;
  top: 8px;
  color: rgba(71, 78, 108, 0.42);
  font: 9px "Cascadia Code", Consolas, monospace;
}
.placement-hint {
  position: absolute;
  z-index: 12;
  top: 16px;
  left: 50%;
  transform: translateX(-50%);
  border: 1px solid var(--cobalt);
  border-radius: 4px;
  padding: 8px 11px;
  color: var(--cobalt);
  background: rgba(247, 248, 255, 0.96);
  box-shadow: var(--shadow);
  font-size: 12px;
}
.canvas-help {
  position: absolute;
  z-index: 8;
  left: 16px;
  bottom: 62px;
  color: #737b99;
  font: 10px/1.3 "Cascadia Code", Consolas, monospace;
}

.lens-bar {
  position: absolute;
  z-index: 10;
  left: 18px;
  right: 150px;
  bottom: 14px;
  display: flex;
  align-items: center;
  gap: 5px;
  min-width: 0;
  overflow-x: auto;
  scrollbar-width: none;
}
.lens-chip {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  border: 1px solid rgba(205, 211, 231, 0.92);
  border-radius: 3px;
  padding: 5px 7px;
  color: var(--muted);
  background: rgba(247, 248, 255, 0.92);
  backdrop-filter: blur(8px);
  font: 600 9px/1 "Cascadia Code", Consolas, monospace;
}
.lens-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--chip-color); }

.zoom-controls {
  position: absolute;
  z-index: 11;
  right: 14px;
  bottom: 14px;
  display: flex;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.94);
}
.zoom-controls button { min-width: 34px; height: 31px; border: 0; border-right: 1px solid var(--line); background: transparent; cursor: pointer; font-size: 12px; }
.zoom-controls button:last-child { border-right: 0; }
.zoom-controls button:hover { color: var(--cobalt); background: var(--cobalt-soft); }

.inspector {
  z-index: 18;
  grid-column: 3;
  grid-row: 2;
  overflow-y: auto;
  border-left: 1px solid var(--line);
  background: var(--paper-solid);
  overscroll-behavior: contain;
}
.inspector-empty { display: grid; place-items: center; align-content: center; min-height: 100%; padding: 28px; text-align: center; color: var(--muted); }
.inspector-empty p { margin: 12px 0 5px; color: var(--ink); font-size: 14px; }
.inspector-empty small { max-width: 190px; line-height: 1.4; }
.empty-glyph { font: 300 42px/1 Bahnschrift, sans-serif; color: var(--line); }

.inspector-content { position: relative; padding: 20px 18px 30px; }
.inspector-close {
  position: absolute;
  top: 12px;
  right: 12px;
  display: grid;
  place-items: center;
  width: 29px;
  height: 29px;
  border: 1px solid var(--line);
  border-radius: 3px;
  background: var(--white);
  cursor: pointer;
  color: var(--muted);
  font-size: 18px;
  line-height: 1;
}
.inspector-close:hover { color: var(--cobalt); border-color: var(--cobalt); }
.inspector-eyebrow { margin: 0 0 6px; color: var(--muted); font: 700 9px/1 "Cascadia Code", Consolas, monospace; letter-spacing: 0.12em; text-transform: uppercase; }
.inspector-heading { margin: 0 0 22px; font: 600 22px/1.1 Bahnschrift, sans-serif; letter-spacing: -0.02em; }
.field { display: grid; gap: 6px; margin-bottom: 15px; }
.field > span { color: var(--muted); font: 650 9px/1 "Cascadia Code", Consolas, monospace; letter-spacing: 0.08em; text-transform: uppercase; }
.field input, .field textarea, .field select {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 3px;
  padding: 9px 10px;
  color: var(--ink);
  background: var(--white);
  font-size: 13px;
}
.field textarea { min-height: 106px; resize: vertical; line-height: 1.4; }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.inspector-code { margin: 18px 0; border-top: 1px solid var(--line); padding-top: 12px; color: var(--muted); font: 9px/1.4 "Cascadia Code", Consolas, monospace; overflow-wrap: anywhere; }
.delete-button { width: 100%; border: 1px solid #e3b4b4; border-radius: 3px; padding: 9px; color: #a33b3b; background: #fff8f8; cursor: pointer; }
.delete-button:hover { background: #ffebeb; }
.relation-direction { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 7px; margin: 0 0 18px; color: var(--muted); font-size: 11px; }
.relation-direction span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.relation-direction strong { color: var(--cobalt); }

.toast {
  position: fixed;
  z-index: 100;
  left: 50%;
  bottom: 22px;
  transform: translate(-50%, 12px);
  max-width: min(420px, calc(100vw - 32px));
  border-radius: 4px;
  padding: 9px 13px;
  color: var(--white);
  background: var(--ink);
  box-shadow: var(--shadow);
  font-size: 12px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 150ms ease, transform 150ms ease;
}
.toast.is-visible { opacity: 1; transform: translate(-50%, 0); }

@media (max-width: 820px) {
  .app-shell { grid-template-columns: 1fr; grid-template-rows: 58px minmax(0, 1fr) 70px; }
  .masthead { grid-column: 1; grid-row: 1; grid-template-columns: 58px minmax(0, 1fr) auto; gap: 9px; height: 58px; }
  .identity { padding-left: 13px; }
  .identity-name, .sync-state span, .top-action span { display: none; }
  .identity-mark { width: 31px; }
  .canvas-title { font-size: 19px; }
  .top-action { margin-right: 9px; width: 36px; padding: 0; }
  .sync-state { position: absolute; right: 54px; top: 8px; }
  .tool-rail {
    grid-column: 1;
    grid-row: 3;
    display: flex;
    align-items: center;
    gap: 8px;
    overflow-x: auto;
    overflow-y: hidden;
    border-top: 1px solid var(--line);
    border-right: 0;
    padding: 8px max(10px, env(safe-area-inset-right)) calc(8px + env(safe-area-inset-bottom)) max(10px, env(safe-area-inset-left));
  }
  .tool-cluster { display: flex; gap: 5px; }
  .rail-rule { display: none; }
  .tool-button { flex: 0 0 48px; display: block; width: 48px; min-height: 52px; padding: 4px; text-align: center; }
  .tool-button > span { margin: 0 auto 3px; }
  .tool-button small { display: block; font-size: 8px; }
  .canvas-region { grid-column: 1; grid-row: 2; }
  .inspector {
    position: fixed;
    z-index: 40;
    left: 10px;
    right: 10px;
    bottom: 80px;
    max-height: min(60vh, 450px);
    border: 1px solid var(--line);
    border-radius: 6px;
    box-shadow: var(--shadow);
    transform: translateY(calc(100% + 100px));
    transition: transform 180ms ease;
  }
  .inspector.has-selection { transform: translateY(0); }
  .inspector-empty { display: none; }
  .inspector-content { padding: 16px 15px 20px; }
  .inspector-heading { margin-bottom: 15px; font-size: 19px; }
  .lens-bar { left: 10px; right: 10px; bottom: 51px; }
  .zoom-controls { right: 10px; bottom: 10px; }
  .canvas-help { left: 10px; bottom: 12px; max-width: calc(100% - 170px); font-size: 9px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }
}