:root {
  --bg: #eef1f4;
  --panel: #f7f9fb;
  --ink: #0b1220;
  --muted: #5b6577;
  --line: #d7dee8;
  --kw: #1d4ed8;
  --str: #c2410c;
  --ok: #0f766e;
  --err: #b91c1c;
  --code: #0b1220;
  --tree-w: 240px;
  --sans: "Figtree", sans-serif;
  --mono: "Azeret Mono", monospace;
}

*,
*::before,
*::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
}

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

.app {
  display: grid;
  grid-template-columns: var(--tree-w) 1fr;
  min-height: 100vh;
}

.tree {
  position: sticky;
  top: 0;
  height: 100vh;
  background: #0b1220;
  color: #cbd5e1;
  padding: 1.1rem 0.9rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  overflow: auto;
  z-index: 30;
}

.tree-brand {
  font-family: var(--mono);
  font-weight: 700;
  color: #fff;
  text-decoration: none;
  font-size: 1rem;
  letter-spacing: -0.03em;
}

.tree-brand span { color: #fb923c; }

.tree-label,
.tree-foot {
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #64748b;
  margin: 0;
}

.tree-foot { margin-top: auto; }

.tree-nav {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.tree-nav a {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: #94a3b8;
  text-decoration: none;
  padding: 0.35rem 0.45rem;
  border-radius: 4px;
}

.tree-nav a:hover,
.tree-nav a.active-file {
  background: rgba(255, 255, 255, 0.06);
  color: #e2e8f0;
}

.tree-nav .dir { color: #38bdf8; }
.tree-nav .nested { padding-left: 1.1rem; }

.workspace { min-width: 0; }

.top {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1.25rem;
  background: rgba(247, 249, 251, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.tree-toggle {
  display: none;
  border: 1px solid var(--line);
  background: #fff;
  font-family: var(--mono);
  font-size: 0.75rem;
  padding: 0.4rem 0.65rem;
  cursor: pointer;
}

.breadcrumb {
  margin: 0;
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--muted);
}

.breadcrumb em { color: var(--ink); font-style: normal; }

.top-mail {
  margin-left: auto;
  font-family: var(--mono);
  font-size: 0.75rem;
  text-decoration: none;
}

.hero {
  padding: clamp(2.5rem, 7vh, 4.5rem) clamp(1.2rem, 4vw, 3rem) 2.5rem;
  background:
    linear-gradient(90deg, rgba(29, 78, 216, 0.06), transparent 40%),
    var(--panel);
  border-bottom: 1px solid var(--line);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-bottom: 1rem;
}

.pill {
  font-family: var(--mono);
  font-size: 0.7rem;
  padding: 0.25rem 0.5rem;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--muted);
}

.brand-hero {
  font-family: var(--mono);
  font-size: clamp(2rem, 5.5vw, 3.8rem);
  font-weight: 700;
  letter-spacing: -0.05em;
  margin: 0 0 0.9rem;
  color: var(--kw);
  line-height: 0.95;
}

.hero h1 {
  font-size: clamp(1.5rem, 3vw, 2.4rem);
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin: 0 0 0.9rem;
  max-width: 18ch;
}

.lede {
  max-width: 52ch;
  color: var(--muted);
  margin: 0 0 1.4rem;
}

.lede mark {
  background: rgba(194, 65, 12, 0.12);
  color: var(--str);
  padding: 0 0.25rem;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-bottom: 2rem;
}

.btn {
  display: inline-flex;
  font-family: var(--mono);
  font-size: 0.8rem;
  font-weight: 600;
  text-decoration: none;
  padding: 0.8rem 1.05rem;
  border: 1px solid transparent;
}

.btn.primary { background: var(--ink); color: #fff; }
.btn.ghost { background: #fff; border-color: var(--line); color: var(--ink); }

.annotation-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.6rem;
}

.anno {
  background: #fff;
  border: 1px dashed var(--line);
  padding: 0.8rem;
  display: grid;
  gap: 0.25rem;
}

.anno b {
  font-family: var(--mono);
  color: var(--str);
  font-size: 0.75rem;
}

.anno span {
  font-size: 0.9rem;
  font-weight: 600;
}

section {
  padding: clamp(3rem, 7vh, 4.5rem) clamp(1.2rem, 4vw, 3rem);
  border-bottom: 1px solid var(--line);
}

.kicker {
  margin: 0 0 0.6rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--str);
  font-weight: 600;
}

h2 {
  font-size: clamp(1.55rem, 3vw, 2.3rem);
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin: 0 0 1rem;
  max-width: 22ch;
}

.section-lead {
  color: var(--muted);
  max-width: 56ch;
  margin: 0 0 1.5rem;
}

.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  background: #fff;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  min-width: 720px;
}

th,
td {
  text-align: left;
  padding: 0.85rem 0.9rem;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

th {
  font-family: var(--mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  background: #f1f5f9;
  color: var(--muted);
}

td code {
  font-family: var(--mono);
  color: var(--kw);
  font-size: 0.85rem;
}

.ast {
  display: grid;
  gap: 0.55rem;
}

.node {
  background: #fff;
  border: 1px solid var(--line);
}

.node summary {
  cursor: pointer;
  list-style: none;
  padding: 0.95rem 1rem;
  font-family: var(--mono);
  font-size: 0.92rem;
  font-weight: 600;
}

.node summary::-webkit-details-marker { display: none; }

.node summary::before {
  content: "▸ ";
  color: var(--kw);
}

.node[open] summary::before { content: "▾ "; }

.kind {
  display: inline-block;
  margin-right: 0.45rem;
  padding: 0.1rem 0.35rem;
  background: rgba(29, 78, 216, 0.1);
  color: var(--kw);
  font-size: 0.7rem;
}

.node-body {
  padding: 0 1rem 1.1rem 1rem;
  border-top: 1px solid var(--line);
}

.node-body p {
  color: var(--muted);
  max-width: 70ch;
}

.node-body ul {
  columns: 2;
  gap: 1.2rem;
  padding-left: 1.1rem;
}

.lint-board {
  display: grid;
  gap: 0.45rem;
  background: var(--code);
  padding: 1rem;
  color: #e2e8f0;
}

.lint-item {
  display: grid;
  grid-template-columns: auto auto 1fr;
  gap: 0.65rem;
  align-items: center;
  font-family: var(--mono);
  font-size: 0.82rem;
  padding: 0.55rem 0.4rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.lint-item span {
  color: #f87171;
  font-size: 0.7rem;
  text-transform: uppercase;
  min-width: 3.2rem;
}

.lint-item:nth-child(3) span,
.lint-item:nth-child(4) span,
.lint-item:nth-child(8) span { color: #fbbf24; }

.lint-item:nth-child(6) span { color: #38bdf8; }

.rfc-card {
  background: #fff;
  border: 1px solid var(--line);
  padding: 0;
}

.rfc-card header {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
  padding: 0.85rem 1rem;
  background: #f8fafc;
  border-bottom: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--muted);
}

.rfc-card ol {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: rfc;
}

.rfc-card li {
  counter-increment: rfc;
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 0.75rem;
  padding: 1rem 1.1rem;
  border-bottom: 1px solid var(--line);
}

.rfc-card li:last-child { border-bottom: 0; }

.rfc-card li::before {
  content: "§" counter(rfc);
  font-family: var(--mono);
  color: var(--kw);
  font-weight: 700;
}

.rfc-card h3 {
  margin: 0 0 0.3rem;
  font-size: 1.05rem;
}

.rfc-card p {
  margin: 0;
  color: var(--muted);
  grid-column: 2;
}

.diff {
  margin-bottom: 1.25rem;
  border: 1px solid var(--line);
  background: #fff;
}

.diff h3 {
  margin: 0;
  padding: 0.85rem 1rem;
  font-family: var(--mono);
  font-size: 0.95rem;
  border-bottom: 1px solid var(--line);
  background: #f8fafc;
}

.diff h3 span {
  color: var(--muted);
  font-weight: 500;
}

.diff h3 span::before { content: " · "; }

.diff-pane {
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.minus,
.plus {
  padding: 1rem;
}

.minus {
  background: rgba(185, 28, 28, 0.05);
  border-right: 1px solid var(--line);
}

.plus { background: rgba(15, 118, 110, 0.06); }

.diff-label {
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 700;
  margin: 0 0 0.55rem;
}

.minus .diff-label { color: var(--err); }
.plus .diff-label { color: var(--ok); }

.diff ul {
  margin: 0;
  padding-left: 1.1rem;
}

.diff-note {
  margin: 0;
  padding: 0.85rem 1rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.95rem;
}

.lexicon dl {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
}

.lexicon dl > div {
  background: #fff;
  border: 1px solid var(--line);
  padding: 1rem;
}

.lexicon dt {
  font-family: var(--mono);
  font-size: 0.88rem;
  color: var(--kw);
  margin-bottom: 0.35rem;
}

.lexicon dd {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.office-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 0.9fr;
  gap: 0.85rem;
}

.office-grid article {
  background: #fff;
  border: 1px solid var(--line);
  padding: 1.2rem;
}

.office-grid h3 {
  margin: 0 0 0.6rem;
  font-size: 1.1rem;
}

.office-grid ul {
  margin: 0;
  padding-left: 1.05rem;
  color: var(--muted);
}

.office-stats {
  background: var(--code) !important;
  color: #e2e8f0;
  display: grid;
  gap: 0.85rem;
  align-content: center;
}

.office-stats p { margin: 0; font-family: var(--mono); font-size: 0.85rem; color: #94a3b8; }

.office-stats strong {
  display: block;
  font-size: 1.8rem;
  color: #fb923c;
  line-height: 1.1;
  margin-bottom: 0.2rem;
}

.error-list {
  display: grid;
  gap: 0.65rem;
}

.error-list article {
  background: #fff7f7;
  border-left: 4px solid var(--err);
  border: 1px solid #fecaca;
  border-left-width: 4px;
  padding: 0.95rem 1rem;
}

.err-code {
  margin: 0 0 0.35rem;
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--err);
  font-weight: 600;
}

.err-fix {
  margin: 0;
  color: var(--muted);
}

.terminal {
  background: var(--code);
  color: #e2e8f0;
  border: 1px solid #1e293b;
  overflow: hidden;
}

.terminal-bar {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.65rem 0.85rem;
  background: #111827;
  border-bottom: 1px solid #1e293b;
}

.terminal-bar span {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #334155;
}

.terminal-bar span:nth-child(1) { background: #f87171; }
.terminal-bar span:nth-child(2) { background: #fbbf24; }
.terminal-bar span:nth-child(3) { background: #34d399; }

.terminal-bar em {
  margin-left: auto;
  font-family: var(--mono);
  font-style: normal;
  font-size: 0.72rem;
  color: #64748b;
}

.terminal-body { padding: 1.1rem 1.15rem 1.4rem; }

.prompt {
  font-family: var(--mono);
  font-size: 0.82rem;
  color: #34d399;
  margin: 0.9rem 0 0.35rem;
}

.prompt:first-child { margin-top: 0; }

.terminal address {
  font-style: normal;
  font-family: var(--mono);
  font-size: 0.9rem;
  line-height: 1.7;
  color: #cbd5e1;
}

.out a {
  font-family: var(--mono);
  color: #fb923c;
}

.terminal form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.7rem;
  margin-top: 0.5rem;
}

.terminal label {
  display: grid;
  gap: 0.3rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: #94a3b8;
}

.terminal .full { grid-column: 1 / -1; }

.terminal input,
.terminal select,
.terminal textarea {
  width: 100%;
  background: #020617;
  border: 1px solid #334155;
  color: #e2e8f0;
  padding: 0.7rem;
  font-family: var(--mono);
  font-size: 0.85rem;
}

.terminal button {
  grid-column: 1 / -1;
  justify-self: start;
  border: 0;
  background: #ea580c;
  color: #fff;
  font-family: var(--mono);
  font-weight: 700;
  padding: 0.8rem 1.1rem;
  cursor: pointer;
}

.note {
  grid-column: 1 / -1;
  margin: 0;
  font-family: var(--mono);
  font-size: 0.8rem;
  color: #5eead4;
}

.readme-foot {
  padding: 1.5rem clamp(1.2rem, 4vw, 3rem) 2rem;
  background: #0b1220;
}

.readme-foot pre {
  margin: 0;
  white-space: pre-wrap;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: #94a3b8;
  line-height: 1.7;
}

.readme-foot a { color: #fb923c; }

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.in {
  opacity: 1;
  transform: none;
}

@media (max-width: 980px) {
  .app { grid-template-columns: 1fr; }

  .tree {
    display: none;
    position: fixed;
    inset: 0 auto 0 0;
    width: min(82vw, 280px);
    box-shadow: 8px 0 30px rgba(0, 0, 0, 0.25);
  }

  .tree.open { display: flex; }

  .tree-toggle { display: inline-flex; }

  .annotation-row,
  .diff-pane,
  .lexicon dl,
  .office-grid,
  .terminal form {
    grid-template-columns: 1fr;
  }

  .minus { border-right: 0; border-bottom: 1px solid var(--line); }

  .node-body ul { columns: 1; }

  .rfc-card li {
    grid-template-columns: 1fr;
  }

  .rfc-card p { grid-column: 1; }
}