/* Night transit diagram: one committed dark look. */
:root {
  --ground: #1c232b;
  --panel: #212931;
  --raised: #2b343f;
  --edge: #38424e;
  --deep: #12171d;
  --text: #e8ecf1;
  --quiet: #9aa5b1;
  --line-1: #f0524a;
  --line-2: #4c8dff;
  --line-3: #2dbe7e;
  --line-4: #f4b63f;
  --line-5: #a57cff;
  --line-6: #33c7d8;
  --line-7: #f2709f;
  --line-8: #ff8f4a;
  --sans: "Overpass", "Helvetica Neue", Arial, sans-serif;
  --mono: "Overpass Mono", ui-monospace, Menlo, Consolas, monospace;
  color-scheme: dark;
}

* { box-sizing: border-box; }

[hidden] { display: none !important; }

body {
  margin: 0;
  background: var(--ground);
  color: var(--text);
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.55;
  font-variant-numeric: tabular-nums;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--text); text-underline-offset: 0.2em; text-decoration-color: var(--quiet); }
a:hover { color: var(--line-2); text-decoration-color: currentColor; }

:focus-visible { outline: 3px solid var(--line-2); outline-offset: 2px; }

.skip {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 10;
  padding: 8px 12px;
  background: var(--text);
  color: var(--ground);
}
.skip:focus { top: 12px; }

button { font: inherit; color: inherit; touch-action: manipulation; }

/* Intro, before the map */

.intro {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
  gap: 16px 56px;
  padding: 36px 32px 28px;
  border-bottom: 1px solid var(--edge);
}

.intro h1 {
  margin: 0 0 10px;
  font-size: 3rem;
  line-height: 1;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.intro p { margin: 0; max-width: 60ch; color: var(--quiet); }
.intro p + p { margin-top: 10px; }
.intro strong { color: var(--text); font-weight: 600; }

.rules {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
  align-content: start;
}

.rules li {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: 12px;
  align-items: start;
  color: var(--quiet);
  font-size: 0.95rem;
}

.rules li b { color: var(--text); font-weight: 600; }
.rules svg { width: 30px; height: 30px; }

@media (max-width: 900px) {
  .intro { grid-template-columns: 1fr; padding: 24px 16px 20px; }
  .intro h1 { font-size: 2.4rem; }
}

/* App frame */

.app {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 8px var(--side, clamp(320px, 32vw, 480px));
  min-height: 92svh;
  border-bottom: 1px solid var(--edge);
}

/* Drag handle between the map and the side panel. */
.resizer {
  position: relative;
  cursor: col-resize;
  touch-action: none;
  background: transparent;
}

.resizer::after {
  content: "";
  position: sticky;
  top: calc(50svh - 24px);
  display: block;
  width: 4px;
  height: 48px;
  margin: 140px auto 0;
  border-radius: 2px;
  background: var(--edge);
  transition: background 0.15s;
}

.resizer:hover::after,
.resizer.dragging::after,
.resizer:focus-visible::after { background: var(--line-2); }

.app.resizing { cursor: col-resize; user-select: none; }

@media (max-width: 900px) {
  .app { grid-template-columns: minmax(0, 1fr); min-height: 0; }
  .resizer { display: none; }
  .side { border-left: 0; border-top: 1px solid var(--edge); padding: 24px 16px; }
  .diagram { min-height: 0; }
}

.board {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 16px;
}

@media (min-width: 720px) { .board { padding: 24px 32px; } }

.diagram {
  position: relative;
  display: grid;
  align-items: center;
  min-height: 340px;
  padding-top: 8px;
  overflow-x: auto;
  overscroll-behavior-x: contain;
}

.diagram svg {
  display: block;
  margin: 0 auto;
  width: 100%;
  height: auto;
  max-height: 64svh;
  min-width: var(--min-width, 0px);
  overflow: visible;
}

@media (max-width: 700px) {
  .diagram svg { min-width: max(var(--min-width, 0px), var(--natural, 0px)); max-height: none; }
}

/* Player */

.player {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 18px;
  margin-top: 12px;
}

.play {
  width: 46px;
  height: 46px;
  border: 0;
  border-radius: 50%;
  background: var(--text);
  display: grid;
  place-items: center;
  cursor: pointer;
  box-shadow: 0 3px 0 var(--deep);
}
.play svg { width: 16px; height: 16px; fill: var(--ground); }
.play:hover { background: var(--line-2); }
.play:active { transform: translateY(2px); box-shadow: 0 1px 0 var(--deep); }

.scrub { position: relative; height: 30px; }
.scrub svg { position: absolute; inset: 0; width: 100%; height: 100%; overflow: visible; }
.scrub input {
  position: absolute;
  inset: -6px 0;
  width: 100%;
  margin: 0;
  opacity: 0;
  cursor: pointer;
}
.scrub:has(input:focus-visible) { outline: 3px solid var(--line-2); outline-offset: 4px; }

.readout {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.3;
  text-align: right;
  white-space: nowrap;
}
.readout b { font-weight: 800; }
.readout span { color: var(--quiet); }

.speed {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 12px;
  font-size: 0.9rem;
  color: var(--quiet);
}

.speed button {
  padding: 2px 0;
  border: 0;
  border-bottom: 2px solid transparent;
  background: none;
  color: var(--quiet);
  cursor: pointer;
}
.speed button:hover { color: var(--text); }
.speed button[aria-pressed="true"] { color: var(--text); border-bottom-color: var(--text); font-weight: 600; }

@media (max-width: 560px) {
  .player { grid-template-columns: auto minmax(0, 1fr); }
  .readout { grid-column: 1 / -1; text-align: left; }
}

/* This turn, in words */

.hint { margin: 8px 0 0; font-size: 0.85rem; color: var(--quiet); }

.story {
  padding: 14px 16px;
  background: var(--panel);
  border: 1px solid var(--edge);
  border-radius: 6px;
  min-height: 132px;
}

.story h2 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 800;
}

.story ul {
  margin: 0;
  padding: 0 4px 0 0;
  max-height: 55svh;
  overflow-y: auto;
  list-style: none;
  display: grid;
  gap: 5px;
  font-size: 0.93rem;
}

.story li { display: flex; flex-wrap: wrap; gap: 4px 10px; align-items: baseline; }
.story li span { flex: 1 1 10rem; }
.story li span { color: var(--quiet); }
.story li span b { color: var(--text); font-weight: 600; }

.chip {
  flex: none;
  display: inline-block;
  min-width: 34px;
  padding: 0 6px;
  border-radius: 3px;
  color: var(--deep);
  font-size: 0.8rem;
  font-weight: 800;
  text-align: center;
  line-height: 1.5;
}

.output {
  margin: 10px 0 0;
  padding-top: 8px;
  border-top: 1px solid var(--edge);
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--quiet);
  overflow-wrap: anywhere;
}

/* Side panel */

.side {
  display: flex;
  flex-direction: column;
  gap: 22px;
  padding: 24px;
  border-left: 1px solid var(--edge);
  background: var(--panel);
  min-width: 0;
}

.side h2 { margin: 0; font-size: 1rem; font-weight: 800; }

.index { position: relative; display: flex; flex-direction: column; }

.index::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 14px;
  bottom: 14px;
  width: 4px;
  background: var(--text);
}

.stop {
  position: relative;
  display: grid;
  grid-template-columns: 18px minmax(0, 1fr);
  column-gap: 12px;
  align-items: start;
  width: 100%;
  padding: 7px 0;
  border: 0;
  background: none;
  text-align: left;
  cursor: pointer;
}

.stop::before {
  content: "";
  position: relative;
  z-index: 1;
  width: 18px;
  height: 18px;
  margin-top: 1px;
  border-radius: 50%;
  background: var(--panel);
  border: 3px solid var(--text);
}

.stop .name { font-weight: 600; line-height: 1.25; }
.stop .meta { grid-column: 2; font-size: 0.85rem; color: var(--quiet); line-height: 1.3; }
.stop:hover .name { color: var(--line-2); }
.stop[aria-current="true"]::before { background: var(--line-2); border-color: var(--text); }
.stop[aria-current="true"] .name { font-weight: 800; }

.edit, .plain {
  align-self: flex-start;
  padding: 0;
  border: 0;
  background: none;
  font-weight: 600;
  text-decoration: underline;
  text-decoration-color: var(--quiet);
  text-underline-offset: 0.2em;
  cursor: pointer;
}
.edit:hover, .plain:hover { color: var(--line-2); }

/* Editor */

.editor { display: flex; flex-direction: column; gap: 10px; min-width: 0; }
.editor label { font-weight: 600; }

textarea {
  width: 100%;
  min-height: 340px;
  resize: vertical;
  padding: 10px;
  border: 1px solid var(--edge);
  border-radius: 4px;
  background: var(--deep);
  color: var(--text);
  font-family: var(--mono);
  font-size: 0.78rem;
  line-height: 1.55;
  white-space: pre;
  overflow: auto;
}

.editor-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 16px; }

.primary {
  padding: 9px 18px;
  border: 0;
  border-radius: 22px;
  background: var(--text);
  color: var(--ground);
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 3px 0 var(--deep);
}
.primary:hover { background: var(--line-2); }
.primary:disabled { opacity: 0.5; cursor: progress; }

.status { margin: 0; font-size: 0.9rem; color: var(--quiet); }
.status.error { color: var(--line-1); font-weight: 600; }

details { font-size: 0.88rem; color: var(--quiet); }
summary { cursor: pointer; color: var(--text); font-weight: 600; }
details pre { margin: 8px 0; font-family: var(--mono); font-size: 0.78rem; white-space: pre-wrap; color: var(--text); }
details p { margin: 0; }

/* What I learned, at the top */

.learned-title { margin: 20px 0 8px; font-size: 1rem; font-weight: 800; }

.learned {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.learned li {
  padding: 3px 10px 2px;
  border: 1px solid var(--edge);
  border-radius: 14px;
  background: var(--panel);
  font-size: 0.86rem;
  color: var(--text);
}

/* After the map */

.outro {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
  gap: 24px 56px;
  padding: 40px 32px 56px;
}

.outro h2 { margin: 0 0 10px; font-size: 1.3rem; font-weight: 800; }
.outro p { margin: 0 0 12px; max-width: 64ch; color: var(--quiet); }
.outro p strong { color: var(--text); font-weight: 600; }

.credits {
  align-self: start;
  padding: 18px 20px;
  background: var(--panel);
  border: 1px solid var(--edge);
  border-radius: 6px;
}

.credits dl { margin: 0; display: grid; gap: 12px; }
.credits dt { font-weight: 800; }
.credits dd { margin: 2px 0 0; color: var(--quiet); font-size: 0.95rem; }

@media (max-width: 900px) {
  .outro { grid-template-columns: 1fr; padding: 32px 16px 48px; }
}

/* Diagram drawing */

.track { fill: none; stroke: var(--edge); stroke-width: 4; stroke-linecap: round; stroke-linejoin: round; }
.tube-shadow { fill: none; stroke: #000; stroke-opacity: 0.45; stroke-width: 10; stroke-linecap: round; stroke-linejoin: round; }
.tube { fill: none; stroke-width: 7; stroke-linecap: round; stroke-linejoin: round; }
.tube-light { fill: none; stroke: #fff; stroke-opacity: 0.3; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.route { transition: opacity 0.2s; }
.route.faded { opacity: 0.15; }
.focus .track, .focus .route { opacity: 0.12; }
.focus .track.lit { opacity: 1; stroke: var(--text); }
.focus .route.lit { opacity: 1; }

.puck-side { fill: var(--deep); }
.puck { fill: var(--raised); stroke: var(--text); stroke-width: 2.5; }
.puck.blocked { fill: var(--panel); stroke: var(--edge); }
.puck.full { stroke: var(--line-1); stroke-width: 3; }

.label {
  font-family: var(--sans);
  font-size: 12px;
  font-weight: 600;
  fill: var(--text);
  paint-order: stroke;
  stroke: var(--ground);
  stroke-width: 5px;
  stroke-linejoin: round;
}
.label.terminus { font-size: 14px; font-weight: 800; }
.label.dim { fill: var(--quiet); font-weight: 400; }

.pip { fill: var(--deep); stroke: var(--quiet); stroke-width: 1.1; }
.pip.taken { fill: var(--text); stroke: var(--text); }
.pip.full { fill: var(--line-1); stroke: var(--line-1); }
.count { font-size: 11px; font-weight: 800; fill: var(--text); }
.hit { fill: transparent; cursor: pointer; }

.drone { cursor: pointer; }
.drone .ground-shadow { fill: #000; opacity: 0.5; }
.drone .arm { stroke: #5c6776; stroke-width: 3; stroke-linecap: round; }
.drone .guard { fill: rgba(255, 255, 255, 0.07); stroke: #8994a2; stroke-width: 1.2; }
.drone .blade { stroke: #d5dce4; stroke-width: 1.6; stroke-linecap: round; opacity: 0.85; }
.drone .spin { transform-box: fill-box; transform-origin: center; }
.playing .drone .spin { animation: spin 0.28s linear infinite; }
.drone.parked { opacity: 0; pointer-events: none; }
.drone .hub { fill: #d5dce4; }
.drone .wait-ring { fill: none; stroke: var(--line-4); stroke-width: 1.6; stroke-dasharray: 3 3; opacity: 0; }
.drone.waiting .wait-ring { opacity: 1; }
.drone.home { opacity: 0.4; }
.drone.home .spin { animation: none; }

@keyframes spin { to { transform: rotate(360deg); } }

@media (prefers-reduced-motion: reduce) {
  .drone .spin { animation: none; }
  .route { transition: none; }
}

.tag {
  position: absolute;
  z-index: 3;
  max-width: 250px;
  padding: 7px 10px;
  background: var(--text);
  color: var(--ground);
  border-radius: 4px;
  font-size: 0.82rem;
  line-height: 1.35;
  pointer-events: none;
  transform: translate(-50%, calc(-100% - 18px));
  visibility: hidden;
}
.tag.on { visibility: visible; }

.intro .learn-link { margin: 16px 0 0; }
.learn-link a { color: var(--line-2); font-weight: 600; text-decoration: none; border-bottom: 1px solid currentColor; }
.learn-link a:hover { color: var(--text); }