/* The Agent Glossary — neutral, dictionary-styled, single-page */

:root {
  --bg: #fafaf7;
  --bg-soft: #f3f2ee;
  --text: #1c1917;
  --text-soft: #57534e;
  --rule: #d6d3d1;
  --rule-soft: #e7e5e4;
  --accent: #7c2d12;
  --accent-soft: #c2410c;
  --link: #7c2d12;
  --link-hover: #9a3412;

  --font-serif: "Charter", "Georgia", "Iowan Old Style", "Palatino Linotype", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Inter", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", "Menlo", "Consolas", "Liberation Mono", monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1c1917;
    --bg-soft: #292524;
    --text: #f5f5f4;
    --text-soft: #a8a29e;
    --rule: #44403c;
    --rule-soft: #292524;
    --accent: #fdba74;
    --accent-soft: #fb923c;
    --link: #fdba74;
    --link-hover: #fed7aa;
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 4.5rem; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-serif);
  font-size: 18px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--link);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

a:hover { color: var(--link-hover); }

/* ---------- masthead ---------- */

.masthead {
  max-width: 760px;
  margin: 0 auto;
  padding: 4rem 1.5rem 2rem;
  text-align: left;
  border-bottom: 1px solid var(--rule);
}

.masthead h1 {
  font-family: var(--font-serif);
  font-size: clamp(2.25rem, 5vw, 3.25rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 0.5rem;
  color: var(--text);
}

.masthead .tagline {
  font-family: var(--font-sans);
  font-size: 1rem;
  color: var(--text-soft);
  margin: 0;
  max-width: 56ch;
}

/* ---------- A–Z nav ---------- */

.atoz {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--bg);
  border-bottom: 1px solid var(--rule);
  padding: 0.75rem 1.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 0.5rem;
  justify-content: center;
  max-width: 100%;
  font-family: var(--font-sans);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  background: color-mix(in srgb, var(--bg) 85%, transparent);
}

.atoz a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 1.75rem;
  height: 1.75rem;
  padding: 0 0.4rem;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text-soft);
  text-decoration: none;
  border-radius: 3px;
  transition: background 0.12s, color 0.12s;
}

.atoz a:hover {
  background: var(--bg-soft);
  color: var(--accent);
}

/* ---------- main ---------- */

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 1rem 1.5rem 4rem;
}

.letter {
  margin: 2.5rem 0 0;
  padding-top: 0.5rem;
}

.letter h2 {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--accent);
  display: inline-block;
  padding-right: 1.5rem;
}

article {
  margin: 0 0 1.75rem;
  scroll-margin-top: 5rem;
}

article h3 {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 700;
  margin: 0 0 0.35rem;
  color: var(--text);
  letter-spacing: -0.01em;
}

article p {
  margin: 0;
  color: var(--text);
}

/* ---------- per-term anchor link ---------- */

.anchor {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 400;
  color: var(--rule);
  text-decoration: none;
  margin-left: 0.4rem;
  opacity: 0;
  transition: opacity 0.15s, color 0.15s;
}

article:hover .anchor,
article:focus-within .anchor {
  opacity: 1;
}

.anchor:hover {
  color: var(--accent);
}

/* Always show anchor on touch devices (no hover state). */
@media (hover: none) {
  .anchor { opacity: 0.5; }
}

/* Highlight the linked-to entry */
article:target h3 {
  color: var(--accent);
}

article:target {
  background: var(--bg-soft);
  padding: 0.75rem 1rem;
  margin-left: -1rem;
  margin-right: -1rem;
  border-left: 3px solid var(--accent);
  border-radius: 2px;
}

/* ---------- footer ---------- */

footer {
  max-width: 760px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
  border-top: 1px solid var(--rule);
  font-family: var(--font-sans);
  font-size: 0.9rem;
  color: var(--text-soft);
}

footer p { margin: 0 0 0.5rem; }

.back-to-top {
  margin-top: 1.5rem;
  font-size: 0.85rem;
}

.back-to-top a {
  color: var(--text-soft);
  text-decoration: none;
}

.back-to-top a:hover {
  color: var(--accent);
}

/* ---------- responsive tweaks ---------- */

@media (max-width: 600px) {
  body { font-size: 17px; }
  .masthead { padding: 2.5rem 1.25rem 1.5rem; }
  main { padding: 0.75rem 1.25rem 3rem; }
  footer { padding: 1.5rem 1.25rem 3rem; }
  .atoz { padding: 0.5rem 0.75rem; gap: 0.15rem 0.3rem; }
  .atoz a { min-width: 1.6rem; height: 1.6rem; font-size: 0.8rem; }
}

/* Print stylesheet — readable as a physical dictionary. */
@media print {
  :root { --bg: #fff; --text: #000; --text-soft: #333; --rule: #999; --accent: #000; }
  .atoz { display: none; }
  body { font-size: 11pt; }
  main { padding: 0; max-width: none; }
  article { page-break-inside: avoid; }
  .anchor { display: none; }
  a { color: inherit; text-decoration: none; }
}