:root {
  color-scheme: light;
  --ink: #17231f;
  --muted: #5d6d65;
  --paper: #f4f0e6;
  --surface: #fffdf7;
  --line: #cfd7cc;
  --moss: #315b4e;
  --moss-deep: #21473c;
  --gold: #c7903d;
  --focus: #8a4f14;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 88% 5%, rgba(199, 144, 61, 0.16), transparent 27rem),
    var(--paper);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
}

a { color: var(--moss-deep); text-underline-offset: 0.2em; }
a:hover { color: var(--focus); }

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 20;
  padding: 0.65rem 0.85rem;
  background: var(--surface);
  transform: translateY(-160%);
}
.skip-link:focus { transform: none; }

.site-header,
footer {
  width: min(1180px, calc(100% - 2rem));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
}

.site-header { padding: 1.25rem 0; }
.brand { display: flex; align-items: center; gap: 0.7rem; text-decoration: none; }
.brand img { width: 42px; height: 42px; }
.brand span { display: grid; line-height: 1.15; }
.brand small { color: var(--muted); }
nav { display: flex; flex-wrap: wrap; gap: 1.1rem; }
nav a { font-weight: 650; text-decoration: none; }

main { width: min(1180px, calc(100% - 2rem)); margin: 0 auto; }
.intro { max-width: 850px; padding: clamp(4rem, 10vw, 8rem) 0 3.5rem; }
.eyebrow {
  margin: 0 0 0.7rem;
  color: var(--moss);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}
h1, h2 { margin: 0; font-family: Georgia, "Times New Roman", serif; line-height: 1.04; }
h1 { max-width: 800px; font-size: clamp(3.2rem, 8vw, 6.8rem); letter-spacing: -0.045em; }
h1 em { color: var(--moss); font-weight: 400; }
h2 { font-size: clamp(1.55rem, 3vw, 2.35rem); }
.lead { max-width: 760px; margin: 1.7rem 0; color: #364a42; font-size: clamp(1.06rem, 2vw, 1.27rem); }

.intro-links { display: flex; flex-wrap: wrap; align-items: center; gap: 0.65rem 1.2rem; }
.intro-links a { font-weight: 700; }
.intro-links .primary-link {
  padding: 0.65rem 1rem;
  border-radius: 999px;
  color: #fff;
  background: var(--moss-deep);
  text-decoration: none;
}

.load-status,
.passage-card,
.graph-panel,
.relations-panel,
.evidence-panel,
.fallback,
.noscript-note {
  border: 1px solid var(--line);
  border-radius: 22px;
  background: rgba(255, 253, 247, 0.88);
  box-shadow: 0 18px 55px rgba(29, 54, 45, 0.06);
}
.load-status { padding: 0.9rem 1rem; }
.load-status.verified { border-color: #8eaf9d; }
.load-status.failed { border-color: #be806e; }

.proof { padding: 1.5rem 0 4rem; }
.passage-card { padding: clamp(1.4rem, 4vw, 2.5rem); }
#source-passage { margin: 0; font-family: "Noto Serif CJK SC", "Songti SC", serif; font-size: clamp(1.5rem, 4vw, 2.7rem); }
.integrity-note { margin: 0.65rem 0 0; color: var(--muted); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 0.72rem; overflow-wrap: anywhere; }

.proof-layout { display: grid; grid-template-columns: minmax(0, 1.45fr) minmax(270px, 0.75fr); gap: 1rem; margin-top: 1rem; }
.graph-panel, .relations-panel, .evidence-panel { padding: clamp(1.25rem, 3vw, 2rem); }
.section-heading { margin-bottom: 1.25rem; }
#concept-graph { width: 100%; height: auto; min-height: 360px; border-radius: 16px; background: #faf8f0; }
.graph-edges line { stroke: #9aab9f; stroke-width: 3; cursor: pointer; }
.graph-edges line:hover, .graph-edges line.selected { stroke: var(--gold); stroke-width: 6; }
.graph-edges marker path, #arrowhead path { fill: #72887b; }
.graph-node circle, .graph-node rect { fill: #e5eadf; stroke: var(--moss); stroke-width: 2; }
.graph-node.subject rect { fill: var(--moss-deep); }
.graph-node text { fill: var(--ink); font-size: 21px; font-weight: 750; }
.graph-node.subject text { fill: #fff; font-size: 18px; text-transform: uppercase; letter-spacing: 0.08em; }

.relation-list { display: grid; gap: 0.55rem; max-height: 505px; overflow: auto; margin: 0; padding: 0 0.2rem 0 0; list-style: none; }
.relation-button {
  width: 100%;
  padding: 0.75rem 0.85rem;
  border: 1px solid var(--line);
  border-radius: 12px;
  color: var(--ink);
  background: var(--surface);
  font: inherit;
  text-align: left;
  cursor: pointer;
}
.relation-button:hover, .relation-button[aria-pressed="true"] { border-color: var(--gold); background: #fff6e7; }
.relation-button strong, .relation-button span { display: block; }
.relation-button strong { color: var(--moss-deep); text-transform: capitalize; }
.relation-button span { color: var(--muted); font-size: 0.85rem; }

.evidence-panel { margin-top: 1rem; scroll-margin-top: 1rem; }
.selected-relation { font-weight: 750; }
#evidence-content article { margin-top: 1rem; padding-top: 1rem; border-top: 1px solid var(--line); }
blockquote { margin: 0; padding: 0.2rem 0 0.2rem 1.2rem; border-left: 4px solid var(--gold); font: 1.5rem/1.5 "Noto Serif CJK SC", "Songti SC", serif; }
dl { display: grid; gap: 0.55rem; margin: 1rem 0 0; }
dl div { display: grid; grid-template-columns: minmax(105px, 0.2fr) 1fr; gap: 0.75rem; }
dt { color: var(--muted); font-weight: 700; }
dd { margin: 0; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 0.8rem; overflow-wrap: anywhere; }

.fallback { display: flex; flex-wrap: wrap; align-items: baseline; gap: 0.45rem 1.2rem; margin: 0 0 4rem; padding: 1.25rem; }
.fallback h2 { width: 100%; font-size: 1.3rem; }
.fallback p { width: 100%; margin: 0; color: var(--muted); }
.noscript-note { padding: 1rem; }

footer { margin-top: 1rem; padding: 2rem 0 3rem; border-top: 1px solid var(--line); flex-wrap: wrap; }
footer span { margin-right: auto; color: var(--muted); }

button:focus-visible, a:focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; }

@media (max-width: 780px) {
  .site-header { align-items: flex-start; }
  .site-header nav { justify-content: flex-end; font-size: 0.9rem; }
  .proof-layout { grid-template-columns: 1fr; }
  .relation-list { max-height: none; }
  dl div { grid-template-columns: 1fr; gap: 0.1rem; }
}

@media (max-width: 520px) {
  .site-header nav { display: none; }
  h1 { font-size: 3.1rem; }
  #concept-graph { min-height: 280px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}