:root {
  --bg: #f5f6f8;
  --panel: #ffffff;
  --panel-2: #fafbfc;
  --ink: #141922;
  --muted: #667085;
  --line: #e5e8ec;
  --side: #0f141c;
  --side-2: #161d27;
  --side-ink: #aeb8c6;
  --side-line: #232c39;
  --accent: #0f766e;
  --accent-2: #14b8a6;
  --accent-soft: #e6f4f2;
  --accent-ink: #0b544e;
  --warn: #b45309;
  --warn-soft: #fdf3e6;
  --bad: #be123c;
  --good: #15803d;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --sans: Inter, system-ui, -apple-system, Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
}

body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 14px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* ─── Sidebar ─── */

aside {
  width: 236px;
  background: var(--side);
  color: var(--side-ink);
  position: fixed;
  left: 0;
  top: 0;
  bottom: 0;
  display: flex;
  flex-direction: column;
  padding: 20px 14px;
  overflow-y: auto;
  z-index: 30;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 4px 8px 18px;
  border-bottom: 1px solid var(--side-line);
  margin-bottom: 14px;
}

.glyph {
  width: 26px;
  height: 26px;
  border-radius: 7px;
  background: linear-gradient(135deg, var(--accent-2), var(--accent));
  display: grid;
  place-items: center;
  color: #04211e;
  font-weight: 800;
  font-size: 13px;
  flex: none;
}

.logo b {
  color: #fff;
  font-size: 14.5px;
  letter-spacing: 0.3px;
}

.logo small {
  display: block;
  color: #5f6b7a;
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
}

aside nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

aside nav a {
  display: flex;
  align-items: center;
  gap: 11px;
  color: var(--side-ink);
  text-decoration: none;
  padding: 10px 12px;
  border-radius: 9px;
  font-weight: 600;
  font-size: 13.5px;
  transition: 0.12s;
}

aside nav a .n {
  width: 20px;
  color: #54617240;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
}

aside nav a:hover {
  background: var(--side-2);
  color: #fff;
}

aside nav a.on {
  background: var(--accent);
  color: #fff;
}

aside nav a.on .n {
  color: #bff0ea;
}

.side-foot {
  margin-top: auto;
  padding: 12px 10px 2px;
  border-top: 1px solid var(--side-line);
  font-size: 10.5px;
  color: #54617f;
  line-height: 1.6;
}

/* ─── Shell ─── */

main {
  margin-left: 236px;
  min-width: 0;
}

.top {
  position: sticky;
  top: 0;
  z-index: 15;
  background: rgba(245, 246, 248, 0.85);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
  padding: 16px 30px;
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 14px;
}

.top h1 {
  margin: 0;
  font-size: 19px;
  font-weight: 800;
  letter-spacing: -0.2px;
}

.top .crumb {
  color: var(--muted);
  font-size: 12.5px;
}

.content {
  padding: 26px 30px 70px;
  max-width: 1180px;
}

/* ─── Typography ─── */

h2 {
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--muted);
  margin: 32px 0 14px;
}

h3 {
  font-size: 15px;
  font-weight: 700;
  margin: 22px 0 6px;
}

h4 {
  font-size: 13px;
  font-weight: 700;
  margin: 16px 0 4px;
}

p,
li {
  color: var(--ink);
}

.lede {
  font-size: 15px;
  color: var(--muted);
  line-height: 1.65;
  max-width: 70ch;
  margin: 0 0 22px;
}

a {
  color: var(--accent);
}

strong {
  font-weight: 700;
}

code {
  font-family: var(--mono);
  font-size: 0.88em;
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 0.08em 0.35em;
}

pre {
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px 18px;
  overflow-x: auto;
  font-size: 12px;
  line-height: 1.55;
  font-family: var(--mono);
}

pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: inherit;
}

.hero {
  background: linear-gradient(120deg, #0f141c, #173030);
  color: #fff;
  border: 1px solid var(--side-line);
  border-radius: 16px;
  padding: 30px 32px;
  margin-bottom: 20px;
}

.hero h2 {
  margin: 0 0 10px;
  font-size: 26px;
  font-weight: 800;
  letter-spacing: -0.4px;
  line-height: 1.15;
  color: #fff;
  text-transform: none;
}

.hero .lede {
  margin: 0;
  color: #b9c6d2;
  max-width: 640px;
}

.hero code {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.16);
  color: #d7e3ea;
}

/* ─── Tables ─── */

.table-wrap {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow-x: auto;
  margin: 14px 0;
}

table {
  border-collapse: collapse;
  width: 100%;
  font-size: 12.5px;
}

th,
td {
  padding: 10px 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
}

th {
  background: var(--panel-2);
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  font-weight: 800;
  color: var(--muted);
  white-space: nowrap;
}

tbody tr:last-child td {
  border-bottom: 0;
}

tbody tr:hover td {
  background: var(--panel-2);
}

/* ─── Callouts ─── */

.note,
.warn {
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 12px;
  padding: 14px 18px;
  margin: 16px 0;
  font-size: 13px;
}

.warn {
  border-left-color: var(--warn);
  background: var(--warn-soft);
}

.note p:first-child,
.warn p:first-child {
  margin-top: 0;
}

.note p:last-child,
.warn p:last-child {
  margin-bottom: 0;
}

/* ─── Cards ─── */

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: 14px;
  margin: 18px 0 8px;
}

.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px;
  transition: 0.14s;
}

.card:hover {
  transform: translateY(-3px);
  border-color: var(--accent);
  box-shadow: 0 10px 26px rgba(15, 118, 110, 0.12);
}

.card h3 {
  margin: 0 0 6px;
  font-size: 15px;
}

.card h3 a {
  text-decoration: none;
  color: var(--ink);
}

.card:hover h3 a {
  color: var(--accent-ink);
}

.card p {
  color: var(--muted);
  margin: 0;
  font-size: 12.5px;
  line-height: 1.5;
}

/* ─── Table of contents ─── */

.toc {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px 18px;
  margin: 18px 0 24px;
}

.toc ul {
  margin: 8px 0 0;
  padding-left: 18px;
  columns: 2;
  column-gap: 2rem;
  font-size: 13px;
}

.toc li {
  margin: 3px 0;
}

.toc strong {
  font-size: 11px;
  letter-spacing: 0.9px;
  text-transform: uppercase;
  color: var(--muted);
  font-weight: 800;
}

/* ─── Tags ─── */

.tag {
  display: inline-block;
  font-size: 9.5px;
  font-weight: 800;
  letter-spacing: 0.4px;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: 999px;
  background: #eef1f4;
  color: #475467;
  vertical-align: middle;
}

.tag.done {
  background: var(--accent-soft);
  color: var(--accent-ink);
}

.tag.todo {
  background: var(--warn-soft);
  color: var(--warn);
}

footer {
  border-top: 1px solid var(--line);
  margin-top: 36px;
  padding-top: 14px;
  color: var(--muted);
  font-size: 11.5px;
}

/* ─── Buttons / controls ─── */

button {
  font-family: inherit;
  cursor: pointer;
  border-radius: 9px;
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--ink);
  padding: 7px 13px;
  font-weight: 600;
  font-size: 12.5px;
  transition: 0.12s;
}

button:hover {
  border-color: var(--accent);
  color: var(--accent-ink);
}

button[disabled] {
  opacity: 0.45;
  cursor: default;
}

button[disabled]:hover {
  border-color: var(--line);
  color: var(--ink);
}

/* ─── Interactive diagram ─── */

.diagram {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  margin: 18px 0 24px;
  overflow: hidden;
}

.diagram-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  background: var(--panel-2);
}

.step-label {
  font-size: 12.5px;
  color: var(--muted);
  min-width: 12rem;
  flex: 1 1 12rem;
}

.step-label b {
  color: var(--ink);
}

.diagram-canvas {
  overflow-x: auto;
  padding: 14px;
  background: var(--panel-2);
}

.diagram-canvas svg {
  display: block;
  min-width: 44rem;
  width: 100%;
  height: auto;
}

.diagram-detail {
  border-top: 1px solid var(--line);
  padding: 14px 16px;
  font-size: 12.5px;
  min-height: 5.5rem;
}

.diagram-detail h4 {
  margin: 0 0 4px;
  font-size: 14px;
}

.diagram-detail p {
  margin: 0 0 6px;
  color: var(--muted);
}

.diagram-detail p:last-child {
  margin-bottom: 0;
}

.diagram-detail .hint {
  color: var(--muted);
  font-style: italic;
}

/* SVG pieces */

.node rect {
  fill: var(--panel);
  stroke: var(--line);
  stroke-width: 1.5;
}

.node.external rect {
  stroke-dasharray: 5 4;
}

.node.chain rect {
  fill: var(--accent-soft);
  stroke: var(--accent);
}

.node.store rect {
  fill: var(--panel-2);
}

.node {
  cursor: pointer;
}

.node text {
  text-anchor: middle;
  fill: var(--ink);
  font-family: var(--sans);
}

.n-title {
  font-size: 13px;
  font-weight: 700;
}

.n-sub {
  font-size: 10.5px;
  fill: var(--muted);
}

.n-key {
  font-size: 9.5px;
  fill: var(--accent);
  letter-spacing: 0.03em;
}

.node:hover rect,
.node:focus rect {
  stroke: var(--accent);
  stroke-width: 2;
}

.node:focus {
  outline: none;
}

.node.is-selected rect {
  stroke: var(--accent);
  stroke-width: 2.5;
}

.edge path {
  fill: none;
  stroke: var(--muted);
  stroke-width: 1.5;
}

marker path {
  fill: var(--muted);
  stroke: none;
}

.lifeline {
  fill: none;
  stroke: var(--line);
  stroke-width: 1.5;
  stroke-dasharray: 4 5;
}

.edge.dashed path {
  stroke-dasharray: 5 4;
}

.edge .pulse {
  fill: var(--accent);
}

.e-label {
  font-size: 10px;
  fill: var(--muted);
  font-family: var(--sans);
}

svg.stepping .node:not(.is-on),
svg.stepping .edge:not(.is-on),
svg.stepping .e-label:not(.is-on) {
  opacity: 0.18;
}

svg.stepping .edge:not(.is-on) .pulse {
  display: none;
}

.node,
.edge,
.e-label {
  transition: opacity 0.25s ease;
}

.n-num {
  font-size: 11px;
  font-weight: 700;
  fill: var(--accent);
  text-anchor: start;
}

/* ─── Endpoint explorer ─── */

.endpoint-explorer {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  margin: 18px 0 24px;
  overflow: hidden;
}

.filters {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  background: var(--panel-2);
}

.filters button {
  border-radius: 999px;
  padding: 6px 12px;
  font-size: 12px;
}

.filters button.on {
  border-color: var(--accent);
  color: var(--accent-ink);
  background: var(--accent-soft);
}

.ep-list {
  list-style: none;
  margin: 0;
  padding: 0;
  max-height: 22rem;
  overflow-y: auto;
}

.ep {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding: 9px 16px;
  border-bottom: 1px solid var(--line);
  cursor: pointer;
}

.ep:hover {
  background: var(--panel-2);
}

.ep.is-selected {
  background: var(--accent-soft);
}

.ep:focus {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

.ep-method {
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.5px;
  border-radius: 999px;
  padding: 2px 8px;
  background: #eef1f4;
  color: #475467;
  min-width: 3.4rem;
  text-align: center;
}

.ep-method.get {
  background: var(--accent-soft);
  color: var(--accent-ink);
}

.ep-method.post {
  background: var(--warn-soft);
  color: var(--warn);
}

.ep-path {
  font-family: var(--mono);
  font-size: 12.5px;
  flex: 1 1 12rem;
}

.ep-detail {
  border-top: 1px solid var(--line);
  padding: 14px 16px;
  font-size: 12.5px;
  min-height: 7rem;
}

.ep-detail h4 {
  margin: 0 0 6px;
  font-size: 14px;
}

.ep-detail pre {
  margin: 8px 0;
}

.ep-detail dl {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 3px 14px;
  margin: 8px 0 0;
  font-size: 12px;
}

.ep-detail dt {
  color: var(--muted);
  font-weight: 700;
}

.ep-detail dd {
  margin: 0;
}

/* ─── Table filter ─── */

.table-filter {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 14px 0 4px;
}

.table-filter input {
  font: inherit;
  font-size: 12.5px;
  color: var(--ink);
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 8px 12px;
  flex: 1 1 18rem;
  max-width: 26rem;
}

.table-filter input:focus {
  outline: none;
  border-color: var(--accent);
}

.filter-count {
  font-size: 11.5px;
  color: var(--muted);
}

/* ─── Responsive ─── */

@media (max-width: 900px) {
  aside {
    position: static;
    width: auto;
    padding: 14px;
  }

  aside nav {
    flex-direction: row;
    flex-wrap: wrap;
  }

  aside nav a {
    padding: 7px 11px;
    font-size: 12.5px;
  }

  aside nav a .n {
    display: none;
  }

  .side-foot {
    display: none;
  }

  main {
    margin-left: 0;
  }

  .top,
  .content {
    padding-left: 16px;
    padding-right: 16px;
  }
}

@media (max-width: 40rem) {
  .toc ul {
    columns: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .node,
  .edge,
  .e-label,
  .card {
    transition: none;
  }
}