/* ───────── Diagram page shell ───────── */

.diagram-canvas {
  min-height: calc(100svh + var(--footer-height));
  padding-bottom: var(--footer-height);
}

.page.page-diagram {
  position: relative;
  height: auto;
  min-height: 100svh;
  z-index: 1;
}

.diagram-main {
  position: relative;
  inset: auto;
  width: 100%;
  height: auto;
  min-height: calc(100svh - var(--header-height));
  overflow: visible;
  padding: calc(var(--header-height) + clamp(32px, 4vw, 56px))
    var(--page-gutter) clamp(64px, 6vw, 100px);
  display: flex;
  flex-direction: column;
  gap: clamp(28px, 3vw, 48px);
}

.page-diagram {
  --diagram-viewport-height: clamp(420px, 68vh, 760px);
  --trace-accent: var(--accent);
  --trace-glow: color-mix(in srgb, var(--accent) 14%, transparent);
  --trace-border: color-mix(in srgb, var(--text-main) 10%, var(--line) 90%);
  --trace-border-strong: color-mix(in srgb, var(--text-main) 16%, var(--line) 84%);
  --trace-duration: 520ms;
}

/* ───────── Header row ───────── */

.diagram-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.diagram-header-left {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.diagram-eyebrow {
  margin: 0;
  font-family: var(--font-code);
  font-size: 13px;
  font-weight: 400;
  line-height: 16px;
  letter-spacing: -0.02em;
}

.diagram-title {
  margin: 0;
  color: var(--text-main);
  font-family: var(--font-display);
  font-size: clamp(32px, 4vw, 51px);
  font-weight: 540;
  line-height: 1;
  letter-spacing: -1px;
}

/* ───────── Tabs ───────── */

.diagram-tabs {
  display: flex;
  gap: 0;
  border: 1px solid var(--line);
}

.diagram-tab {
  position: relative;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  -webkit-tap-highlight-color: transparent;
}

.diagram-tab + .diagram-tab {
  border-left: 1px solid var(--line);
}

.diagram-tab-radio {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
  pointer-events: none;
}

.diagram-tab-label {
  display: block;
  padding: 10px 24px;
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 430;
  line-height: 20px;
  letter-spacing: 0;
  text-transform: uppercase;
  color: var(--text-muted);
  transition:
    color 0.2s ease,
    background 0.2s ease;
  white-space: nowrap;
  user-select: none;
}

.diagram-tab-radio:checked + .diagram-tab-label {
  color: var(--text-main);
  background: rgba(238, 237, 228, 0.06);
}

.diagram-tab-radio:focus-visible + .diagram-tab-label {
  color: var(--accent);
  outline: 1px solid var(--accent);
  outline-offset: -1px;
}

@media (hover: hover) and (pointer: fine) {
  .diagram-tab:hover .diagram-tab-label {
    color: var(--accent);
  }
}

@media (hover: none), (pointer: coarse) {
  .diagram-tab:active .diagram-tab-label {
    color: var(--accent);
  }
}

/* ───────── Viewport & SVG ───────── */

.diagram-viewport {
  position: relative;
  width: 100%;
  flex: 0 0 auto;
  height: var(--diagram-viewport-height);
  min-height: 0;
  overflow: hidden;
  padding: clamp(12px, 1.8vw, 20px);
  border: 1px solid color-mix(in srgb, var(--text-main) 5%, transparent);
  background: color-mix(in srgb, var(--page-bg) 96%, var(--text-main) 4%);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.01);
  user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
  touch-action: auto;
  overscroll-behavior: auto;
  cursor: default;
}

.diagram-viewport.is-interactive {
  touch-action: none;
  overscroll-behavior: contain;
  cursor: grab;
}

.diagram-viewport.is-interactive.is-panning {
  cursor: grabbing;
}

.diagram-viewport.is-locked {
  touch-action: auto;
  overscroll-behavior: auto;
  cursor: default;
}

.diagram-canvas-hint {
  display: inline-flex;
  position: absolute;
  top: 8px;
  left: 10px;
  z-index: 2;
  align-items: center;
  gap: 7px;
  margin: 0;
  padding: 3px 5px;
  color: color-mix(in srgb, var(--text-muted) 88%, var(--text-main) 12%);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition:
    opacity 140ms ease,
    visibility 140ms step-end;
}

.diagram-canvas-hint.is-visible {
  opacity: 1;
  visibility: visible;
  transition:
    opacity 140ms ease,
    visibility 0s step-start;
}

.diagram-canvas-hint-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 12px;
  height: 12px;
  color: currentColor;
  flex: 0 0 auto;
}

.diagram-canvas-hint-icon svg {
  width: 12px;
  height: 12px;
}

.diagram-canvas-hint-text {
  font-family: var(--font-sans);
  font-size: 11px;
  font-weight: 400;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.diagram-panzoom {
  position: absolute;
  top: 0;
  left: 0;
  transform-origin: 0 0;
  will-change: transform;
  contain: layout paint style;
  backface-visibility: hidden;
}

.diagram-lines {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
}

.diagram-lines path {
  vector-effect: non-scaling-stroke;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
  transition:
    stroke 0.22s ease,
    opacity 0.22s ease,
    stroke-width 0.22s ease,
    filter 0.22s ease;
}

/* ───────── Tree layout ───────── */

.diagram-tree {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: clamp(48px, 5.5vw, 80px);
  width: max-content;
  z-index: 1;
}

.diagram-tree[hidden] {
  display: none !important;
}

.diagram-row {
  display: flex;
  justify-content: center;
  gap: clamp(16px, 2vw, 32px);
  width: max-content;
  flex-wrap: nowrap;
}

.diagram-tree-precise {
  --diagram-grid-columns: 15;
  --diagram-grid-column-width: clamp(104px, 6.9vw, 116px);
  --diagram-grid-gap: clamp(5px, 0.55vw, 8px);
  gap: clamp(40px, 4.2vw, 56px);
}

.diagram-tree-method {
  --diagram-grid-columns: 10;
  --diagram-grid-column-width: clamp(100px, 6.4vw, 110px);
  --diagram-grid-gap: clamp(4px, 0.4vw, 6px);
  gap: clamp(40px, 4.2vw, 56px);
}

.diagram-tree-precise .diagram-row,
.diagram-tree-method .diagram-row {
  display: grid;
  grid-template-columns: repeat(
    var(--diagram-grid-columns),
    minmax(var(--diagram-grid-column-width), var(--diagram-grid-column-width))
  );
  column-gap: var(--diagram-grid-gap);
  row-gap: 0;
  width: max-content;
  align-items: start;
}

/* ───────── Nodes ───────── */

.diagram-node {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 6px;
  width: clamp(140px, 14vw, 196px);
  padding: 14px 16px;
  border: 1px solid var(--line);
  background: var(--page-bg);
  user-select: none;
  outline: none;
  transition:
    border-color 0.2s ease,
    box-shadow 0.2s ease,
    background-color 0.2s ease,
    opacity 0.2s ease,
    transform 0.2s ease;
  z-index: 1;
}

.diagram-tree-precise .diagram-node {
  justify-self: center;
  width: clamp(98px, 6.2vw, 108px);
  min-height: 76px;
  padding: 9px 9px 10px;
}

.diagram-tree-method .diagram-node {
  justify-self: center;
  width: clamp(98px, 6.1vw, 108px);
  min-height: 76px;
  padding: 8px 8px 9px;
}

.diagram-tree-precise .diagram-node--mid {
  width: clamp(124px, 7.6vw, 140px);
}

.diagram-tree-method .diagram-node--mid {
  width: clamp(116px, 7.2vw, 128px);
}

.diagram-tree-precise .diagram-node--wide {
  width: clamp(150px, 9vw, 172px);
}

.diagram-tree-method .diagram-node--wide {
  width: clamp(148px, 9vw, 166px);
}

.diagram-tree-method .diagram-node--method {
  width: clamp(168px, 10.2vw, 188px);
  min-height: 84px;
  padding: 9px 10px 11px;
}

.diagram-node-id {
  margin: 0;
  font-family: var(--font-code);
  font-size: 12px;
  font-weight: 400;
  line-height: 15px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: color-mix(in srgb, var(--text-main) 72%, var(--text-muted) 28%);
}

.diagram-tree-precise .diagram-node-id {
  font-size: 12px;
  line-height: 15px;
  letter-spacing: -0.03em;
  text-transform: none;
}

.diagram-tree-method .diagram-node-id {
  font-size: 12px;
  line-height: 15px;
  letter-spacing: -0.03em;
  text-transform: none;
}

.diagram-node-id mjx-container {
  margin: 0 !important;
  color: inherit;
  font-size: 1.06em !important;
  line-height: 1;
}

.diagram-node-id mjx-container[jax="CHTML"] {
  display: inline-block;
}

.diagram-node-desc {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 430;
  line-height: 17px;
  letter-spacing: -0.01em;
  color: var(--text-main);
}

.diagram-tree-precise .diagram-node-desc {
  font-size: 11px;
  line-height: 14px;
}

.diagram-tree-method .diagram-node-desc {
  font-size: 12px;
  line-height: 15px;
}

.diagram-node-desc mjx-container {
  margin: 0 !important;
  color: inherit;
  font-size: 1em !important;
}

@media (hover: hover) and (pointer: fine) {
  .diagram-node:hover {
    border-color: var(--text-muted);
  }
}

.diagram-node:focus-visible {
  border-color: var(--trace-accent);
}

.diagram-link {
  opacity: 0.5;
}

.diagram-tree.has-active-trace .diagram-node {
  opacity: 0.4;
}

.diagram-tree.has-active-trace .diagram-link {
  opacity: 0.12;
}

.diagram-tree.has-active-trace .diagram-node.is-trace-origin,
.diagram-tree.has-active-trace .diagram-node.is-trace-node {
  opacity: 1;
}

.diagram-node.is-trace-origin {
  border-color: var(--trace-border-strong);
  background: var(--page-bg);
  box-shadow: none;
}

.diagram-node.is-trace-node {
  border-color: var(--trace-border);
  background: var(--page-bg);
}

.diagram-node.is-trace-origin .diagram-node-id,
.diagram-node.is-trace-node .diagram-node-id {
  color: color-mix(in srgb, var(--accent) 72%, var(--text-muted) 28%);
}

.diagram-node.is-trace-origin .diagram-node-id mjx-container,
.diagram-node.is-trace-node .diagram-node-id mjx-container {
  color: color-mix(in srgb, var(--accent) 82%, var(--text-main) 18%);
}

.diagram-link.is-traced {
  stroke: var(--trace-accent);
  stroke-width: 1.35;
  opacity: 1;
  filter: drop-shadow(0 0 8px var(--trace-glow));
  stroke-dashoffset: 0;
}

.diagram-link.is-traced:not(.is-restored) {
  stroke-dasharray: 100;
  stroke-dashoffset: 100;
  animation: trace-line var(--trace-duration) cubic-bezier(0.22, 0.8, 0.28, 1)
    both;
  animation-delay: calc(var(--trace-depth, 0) * 70ms);
}

@keyframes trace-line {
  from {
    stroke-dashoffset: 100;
    opacity: 0.14;
  }

  to {
    stroke-dashoffset: 0;
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .diagram-node,
  .diagram-lines path {
    transition-duration: 0.01ms;
  }

  .diagram-link.is-traced {
    animation: none;
  }

  .diagram-link.is-traced:not(.is-restored) {
    animation: none;
  }
}

/* ───────── Breakpoints ───────── */

@media (max-width: 960px) {
  .diagram-main {
    padding-left: var(--page-gutter);
    padding-right: var(--page-gutter);
  }

  .page-diagram .menu-center,
  .page-diagram .menu-right {
    display: none;
  }

  .page-diagram .hamburger {
    display: flex;
  }

  .page-diagram .drawer {
    display: block;
  }

  .diagram-node {
    width: 170px;
    padding: 12px 14px;
  }

  .diagram-tree-precise {
    --diagram-grid-column-width: 94px;
    --diagram-grid-gap: 6px;
  }

  .diagram-tree-method {
    --diagram-grid-column-width: 86px;
    --diagram-grid-gap: 4px;
  }

  .diagram-tree-precise .diagram-node {
    width: 90px;
    min-height: 72px;
    padding: 8px 8px 10px;
  }

  .diagram-tree-method .diagram-node {
    width: 82px;
    min-height: 70px;
    padding: 7px 7px 8px;
  }

  .diagram-tree-precise .diagram-node--mid {
    width: 112px;
  }

  .diagram-tree-method .diagram-node--mid {
    width: 98px;
  }

  .diagram-tree-precise .diagram-node--wide {
    width: 134px;
  }

  .diagram-tree-method .diagram-node--wide {
    width: 128px;
  }

  .diagram-tree-method .diagram-node--method {
    width: 140px;
    min-height: 78px;
    padding: 8px 9px 10px;
  }

  .diagram-row {
    gap: 12px;
  }

  .diagram-tree {
    gap: clamp(40px, 6vw, 64px);
  }

  .diagram-tabs {
    width: 100%;
  }

  .diagram-tab {
    flex: 1;
  }

  .diagram-tab-label {
    text-align: center;
    width: 100%;
    padding: 10px 16px;
  }
}

@media (max-width: 560px) {
  .diagram-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 20px;
  }

  .diagram-canvas-hint {
    top: 8px;
    left: 10px;
    padding: 3px 5px;
  }

  .diagram-canvas-hint-text {
    font-size: 11px;
  }

  .diagram-node {
    width: 150px;
    padding: 10px 12px;
  }

  .diagram-tree-precise {
    --diagram-grid-column-width: 84px;
    --diagram-grid-gap: 5px;
  }

  .diagram-tree-method {
    --diagram-grid-column-width: 70px;
    --diagram-grid-gap: 3px;
  }

  .diagram-tree-precise .diagram-node {
    width: 80px;
    min-height: 66px;
    padding: 7px 7px 9px;
  }

  .diagram-tree-method .diagram-node {
    width: 68px;
    min-height: 62px;
    padding: 6px 6px 7px;
  }

  .diagram-tree-precise .diagram-node--mid {
    width: 100px;
  }

  .diagram-tree-method .diagram-node--mid {
    width: 80px;
  }

  .diagram-tree-precise .diagram-node--wide {
    width: 118px;
  }

  .diagram-tree-method .diagram-node--wide {
    width: 96px;
  }

  .diagram-tree-method .diagram-node--method {
    width: 108px;
    min-height: 72px;
    padding: 7px 8px 9px;
  }

  .diagram-node-desc {
    font-size: 12px;
    line-height: 15px;
  }

  .diagram-tree-precise .diagram-node-id {
    font-size: 11px;
    line-height: 14px;
  }

  .diagram-tree-precise .diagram-node-desc {
    font-size: 10px;
    line-height: 13px;
  }

  .diagram-tree-method .diagram-node-id {
    font-size: 11px;
    line-height: 14px;
  }

  .diagram-tree-method .diagram-node-desc {
    font-size: 10px;
    line-height: 13px;
  }

  .diagram-tree {
    gap: clamp(36px, 8vw, 56px);
  }

  .diagram-row {
    gap: 10px;
  }
}