:root {
  --bg: #f2f0e9;
  --grid: rgba(46, 86, 57, .055);
  --ink: #171a17;
  --muted: #667066;
  --line: #56705d;
  --line-soft: #aebcaf;
  --card: #fbfaf6;
  --accent: #2e5639;
  --accent-soft: #dce6dc;
  --shadow: none;
  --shadow-hover: 0 3px 10px rgba(20, 30, 20, .1);
}

* { box-sizing: border-box; }

html,
body {
  margin: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: 'Frutiger', Arial, Helvetica, sans-serif;
  color: var(--ink);
  background: var(--bg);
}

button,
a,
summary { font: inherit; }

button { color: inherit; }

.canvas-shell {
  position: fixed;
  inset: 0;
  overflow: hidden;
  background: var(--bg);
  cursor: default;
  user-select: none;
  touch-action: none;
}

.canvas-shell.pan-ready { cursor: grab; }
.canvas-shell.panning { cursor: grabbing; }

.canvas-grid {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 32px 32px;
  background-position: 0 0;
}

/* Fixed UI */
.canvas-nav,
.canvas-help,
.zoom-controls,
.block-inspector {
  position: fixed;
  z-index: 100;
  border: 1px solid rgba(201, 206, 197, .95);
  background: rgba(251, 250, 246, .94);
  box-shadow: none;
}

.canvas-nav {
  top: 18px;
  left: 18px;
  display: flex;
  align-items: center;
  gap: 16px;
  max-width: calc(100vw - 84px);
  padding: 8px 10px 8px 12px;
  border-radius: 5px;
}

.back-link {
  color: var(--accent);
  text-decoration: none;
  font-size: .83rem;
  font-weight: 700;
  white-space: nowrap;
}

.jump-links {
  display: flex;
  gap: 5px;
}

.jump-links button,
.zoom-controls button,
.compare-actions button {
  border: 0;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
}

.jump-links button {
  padding: 6px 8px;
  border-radius: 7px;
  font-size: .76rem;
  white-space: nowrap;
}

.jump-links button:hover,
.jump-links button:focus-visible,
.compare-actions button:hover,
.compare-actions button:focus-visible {
  background: var(--accent-soft);
  color: var(--accent);
  outline: none;
}

.compare-menu {
  position: relative;
  margin-left: 2px;
}

.compare-menu summary {
  padding: 6px 9px;
  border-radius: 7px;
  color: var(--accent);
  font-size: .76rem;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
  white-space: nowrap;
}

.compare-menu summary::-webkit-details-marker { display: none; }
.compare-menu summary::after { content: ' ▾'; }
.compare-menu[open] summary { background: var(--accent-soft); }

.compare-popover {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  width: 250px;
  display: grid;
  gap: 8px;
  padding: 14px;
  border: 1px solid rgba(201, 206, 197, .95);
  border-radius: 5px;
  background: rgba(251, 250, 246, .98);
  box-shadow: none;
  color: var(--muted);
  font-size: .78rem;
}

.compare-heading {
  margin-bottom: 2px;
  color: var(--accent);
  font-size: .69rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.compare-popover label {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
}

.compare-popover input { accent-color: var(--accent); }

.compare-actions {
  display: flex;
  gap: 6px;
  padding-top: 4px;
  border-top: 1px solid rgba(174, 188, 175, .55);
}

.compare-actions button {
  padding: 5px 7px;
  border-radius: 6px;
  font-size: .72rem;
}

.canvas-help {
  left: 18px;
  bottom: 18px;
  display: grid;
  gap: 2px;
  padding: 10px 13px;
  border-radius: 5px;
  color: var(--muted);
  font-size: .72rem;
}

.canvas-help strong {
  color: var(--accent);
  font-size: .72rem;
  text-transform: uppercase;
  letter-spacing: .08em;
}

.touch-help { display: none; }

kbd {
  padding: 1px 5px;
  border: 1px solid var(--line-soft);
  border-radius: 4px;
  background: white;
  font-family: inherit;
  font-size: .68rem;
}

.canvas-info {
  position: fixed;
  top: 18px;
  right: 18px;
  z-index: 120;
}

.info-trigger {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(201, 206, 197, .95);
  border-radius: 50%;
  background: rgba(251, 250, 246, .96);
  box-shadow: 0 8px 24px rgba(20,30,20,.08);
  backdrop-filter: blur(10px);
  color: var(--accent);
  cursor: pointer;
  list-style: none;
}

.info-trigger::-webkit-details-marker { display: none; }

.info-icon {
  display: grid;
  place-items: center;
  width: 18px;
  height: 18px;
  border: 1.5px solid currentColor;
  border-radius: 50%;
  font-family: Georgia, serif;
  font-size: 12px;
  font-weight: 700;
  line-height: 1;
}

.info-popover {
  position: absolute;
  top: 44px;
  right: 0;
  width: 340px;
  max-width: calc(100vw - 36px);
  padding: 16px 18px;
  border: 1px solid rgba(201, 206, 197, .95);
  border-radius: 12px;
  background: rgba(251, 250, 246, .98);
  box-shadow: 0 10px 28px rgba(20,30,20,.10);
  color: var(--muted);
  font-size: .78rem;
  line-height: 1.5;
}

.info-popover p { margin: 0; }

.zoom-controls {
  right: 18px;
  bottom: 18px;
  display: grid;
  overflow: hidden;
  border-radius: 12px;
}

.zoom-controls button {
  width: 40px;
  height: 38px;
  font-size: 1.1rem;
  border-bottom: 1px solid var(--line-soft);
}

.zoom-controls button:last-child { border-bottom: 0; }
.zoom-controls button:hover { background: var(--accent-soft); color: var(--accent); }

.block-inspector {
  top: 72px;
  right: 18px;
  width: min(390px, calc(100vw - 36px));
  padding: 18px 20px 20px;
  border-radius: 14px;
  color: var(--ink);
}

.block-inspector[hidden] { display: none; }

.inspector-close {
  position: absolute;
  top: 8px;
  right: 10px;
  width: 30px;
  height: 30px;
  border: 0;
  border-radius: 50%;
  background: transparent;
  color: var(--muted);
  font-size: 22px;
  cursor: pointer;
}

.inspector-close:hover { background: var(--accent-soft); color: var(--accent); }

.inspector-kicker,
.inspector-code {
  color: var(--accent);
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.block-inspector h2 {
  margin: 7px 30px 6px 0;
  font-size: 21px;
  line-height: 1.1;
  letter-spacing: -.025em;
}

.inspector-code { margin-bottom: 10px; }
.block-inspector p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.5; }

/* Diagram world */
.world {
  position: absolute;
  left: 0;
  top: 0;
  width: 4600px;
  height: 4200px;
  transform-origin: 0 0;
  will-change: transform;
}

.connectors {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow: visible;
  z-index: 2;
  pointer-events: none;
}

.connectors path.relationship {
  fill: none;
  stroke: var(--line);
  stroke-width: 4;
  vector-effect: non-scaling-stroke;
}

.connectors path.relationship.dashed {
  stroke-dasharray: 8 8;
}

.relationship-arrowhead {
  fill: var(--line);
  stroke: var(--line);
  stroke-width: 1;
  vector-effect: non-scaling-stroke;
}

.edge-label text {
  fill: #3f5144;
  font-size: 14px;
  font-weight: 700;
  dominant-baseline: middle;
  text-anchor: middle;
}

.edge-label rect {
  fill: rgba(242, 240, 233, .98);
  stroke: rgba(174, 188, 175, .9);
  stroke-width: 1;
  rx: 7;
}

.diagram-heading {
  position: absolute;
  left: 130px;
  top: 110px;
  width: 980px;
  z-index: 5;
}

.eyebrow,
.stack-type {
  display: block;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.diagram-heading h1 {
  margin: 6px 0 9px;
  font-size: 48px;
  line-height: .98;
  letter-spacing: -.045em;
}

.diagram-heading p {
  max-width: 760px;
  margin: 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.5;
}

.stack-column {
  --stack-colour: #00b0a6;
  --stack-colour-dark: #008b83;
  position: absolute;
  top: 350px;
  width: 320px;
  z-index: 5;
  transition: left 220ms ease, opacity 180ms ease, transform 180ms ease;
}

.stack-column[data-column='act'] {
  --stack-colour: #5b3c45;
  --stack-colour-dark: #432c33;
}

.stack-column[data-column='vpp'] {
  --stack-colour: #5C1969;
  --stack-colour-dark: #45114f;
}

.stack-column[data-column='scheme'],
.municipal-column {
  --stack-colour: #00b0a6;
  --stack-colour-dark: #008b83;
}

.stack-heading {
  min-height: 170px;
  padding: 0 4px 22px;
  border-bottom: 1px solid rgba(86, 112, 93, .24);
}

.stack-heading h2 {
  margin: 8px 0 8px;
  font-size: 27px;
  line-height: 1.05;
  letter-spacing: -.035em;
}

.stack-heading p {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.45;
}

.stack-list {
  display: grid;
  gap: 42px;
  padding-top: 30px;
}

.scheme-block {
  position: relative;
  z-index: 3;
  width: 100%;
  aspect-ratio: 1 / 1;
  min-height: 0;
  display: grid;
  align-content: start;
  justify-items: start;
  gap: 10px;
  padding: 20px 22px;
  border: 0;
  border-radius: 0;
  background: var(--stack-colour);
  color: #f8fffd;
  box-shadow:
    8px 8px 0 color-mix(in srgb, var(--stack-colour) 84%, white),
    16px 16px 0 color-mix(in srgb, var(--stack-colour) 70%, white),
    0 16px 28px rgba(30, 45, 38, .12);
  text-align: left;
  cursor: pointer;
  transition: transform 150ms ease, box-shadow 150ms ease, filter 150ms ease;
}

.scheme-block:hover,
.scheme-block:focus-visible,
.scheme-block.is-selected {
  z-index: 8;
  transform: translate(-4px, -4px);
  filter: saturate(1.04);
  box-shadow:
    10px 10px 0 color-mix(in srgb, var(--stack-colour) 84%, white),
    20px 20px 0 color-mix(in srgb, var(--stack-colour) 70%, white),
    0 22px 42px rgba(30, 45, 38, .18);
  outline: none;
}

.scheme-block.is-selected {
  box-shadow:
    0 0 0 4px rgba(255,255,255,.78),
    0 0 0 8px var(--stack-colour-dark),
    10px 10px 0 color-mix(in srgb, var(--stack-colour) 84%, white),
    20px 20px 0 color-mix(in srgb, var(--stack-colour) 70%, white),
    0 22px 42px rgba(30,45,38,.18);
}

.block-code {
  display: inline-flex;
  align-items: center;
  min-height: 24px;
  padding: 4px 8px;
  border: 1px solid rgba(255,255,255,.42);
  border-radius: 999px;
  background: rgba(0,0,0,.08);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .08em;
}

.scheme-block strong {
  max-width: 100%;
  font-size: 22px;
  line-height: 1.06;
  letter-spacing: -.03em;
}

.scheme-block small {
  max-width: 100%;
  color: rgba(248,255,253,.84);
  font-size: 12px;
  line-height: 1.35;
}

.act-column .scheme-block strong {
  font-size: 21px;
}

.act-column .scheme-block small {
  font-size: 11px;
}

.vpp-column .scheme-block small,
.scheme-column .scheme-block small,
.municipal-column .scheme-block small {
  font-size: 11px;
  line-height: 1.28;
}

.municipal-column .stack-heading {
  border-bottom-color: rgba(0, 176, 166, .35);
}

.municipal-column .stack-type { color: var(--stack-colour-dark); }
.municipal-column .scheme-block { opacity: .95; }

.stack-column.is-hidden {
  display: none;
}

.canvas-shell.pan-ready .scheme-block,
.canvas-shell.panning .scheme-block {
  pointer-events: none;
}

@media (max-width: 900px) {
  .canvas-nav {
    right: 62px;
    left: 12px;
    top: 12px;
    gap: 8px;
    overflow-x: auto;
  }

  .jump-links button:nth-child(2),
  .jump-links button:nth-child(3) { display: none; }

  .canvas-info { top: 12px; right: 12px; }
  .canvas-help { left: 12px; bottom: 12px; }
  .zoom-controls { right: 12px; bottom: 12px; }
  .block-inspector { top: 66px; right: 12px; }
}

@media (hover: none), (pointer: coarse) {
  .desktop-help { display: none; }
  .touch-help { display: inline; }
}