/* Robert Arons — site styles. No build step; edit directly. */
:root {
  --bg: #fcfbf8;
  --surface: #ffffff;
  --text: #1f1d1a;
  --muted: #5c5750;          /* 7.1:1 on bg */
  --accent: #7a6647;         /* refined brown-gold, 5.3:1 on bg (links, small caps labels) */
  --accent-soft: #857251;    /* original site color, decorative rules only */
  --rule: #e6e1d8;
  --focus: #2f5d8a;
  --serif: "Source Serif 4", "Source Serif Pro", Georgia, Cambria, "Times New Roman", serif;
  --sans: "Source Sans 3", "Source Sans Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --measure: 42rem;
  --wide: 60rem;
}

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

html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 0.18em; }
a:hover { color: var(--text); text-decoration-thickness: 2px; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; border-radius: 2px; }

h1, h2, h3 {
  font-family: var(--serif);
  font-weight: 600;
  line-height: 1.25;
  color: var(--text);
  letter-spacing: -0.005em;
}

.skip-link {
  position: absolute; left: 1rem; top: -3rem;
  background: var(--text); color: #fff; padding: 0.5rem 0.9rem; z-index: 10;
  border-radius: 0 0 4px 4px; text-decoration: none;
}
.skip-link:focus { top: 0; color: #fff; }

/* ---------- Header / nav ---------- */
.site-header { border-bottom: 1px solid var(--rule); background: var(--bg); }
.site-header .inner {
  max-width: var(--wide); margin: 0 auto; padding: 1.4rem 1.5rem;
  display: flex; flex-wrap: wrap; align-items: baseline; justify-content: space-between; gap: 0.5rem 2rem;
}
.site-name {
  font-family: var(--serif); font-size: 1.4rem; font-weight: 600;
  color: var(--text); text-decoration: none; letter-spacing: 0.01em;
}
.site-name:hover { color: var(--accent); }
.site-nav ul { list-style: none; margin: 0; padding: 0; display: flex; gap: 1.75rem; }
.site-nav a {
  color: var(--muted); text-decoration: none; font-size: 0.95rem;
  letter-spacing: 0.06em; text-transform: uppercase; padding: 0.25rem 0;
  border-bottom: 2px solid transparent;
}
.site-nav a:hover { color: var(--text); border-bottom-color: var(--rule); }
.site-nav a[aria-current="page"] { color: var(--text); border-bottom-color: var(--accent-soft); }

/* ---------- Main ---------- */
main { flex: 1; width: 100%; max-width: var(--wide); margin: 0 auto; padding: 3.5rem 1.5rem 4.5rem; }

.page-title { font-size: clamp(2rem, 1.6rem + 1.6vw, 2.6rem); margin: 0 0 0.5rem; }
.page-intro { color: var(--muted); max-width: var(--measure); margin: 0 0 3rem; }
.page-title::after {
  content: ""; display: block; width: 3rem; height: 2px; margin-top: 1rem; background: var(--accent-soft);
}

.section-title {
  font-size: 0.85rem; font-family: var(--sans); font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.12em; color: var(--accent);
  margin: 3rem 0 1.25rem; padding-bottom: 0.6rem; border-bottom: 1px solid var(--rule);
}
main section:first-of-type .section-title { margin-top: 0; }
main section + section { margin-top: 3.5rem; }
main section { max-width: 48rem; }

/* ---------- Home ---------- */
.intro {
  display: grid; grid-template-columns: minmax(0, 17rem) minmax(0, 1fr);
  gap: 3.5rem; align-items: start;
}
.portrait img {
  width: 100%; aspect-ratio: 480 / 705; object-fit: cover;
  border-radius: 3px; background: #eee;
  box-shadow: 0 1px 2px rgba(31,29,26,.06), 0 10px 30px -12px rgba(31,29,26,.25);
}
.bio h1 { font-size: clamp(2.2rem, 1.7rem + 2vw, 3rem); margin: 0 0 0.25rem; }
.bio .tagline {
  font-family: var(--serif); font-style: italic; font-size: 1.2rem; color: var(--muted); margin: 0 0 1.75rem;
}
.bio p { max-width: var(--measure); }
.bio h2 {
  font-size: 0.85rem; font-family: var(--sans); font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.12em; color: var(--accent); margin: 2.25rem 0 0.6rem;
}
.interests { list-style: none; padding: 0; margin: 0; display: flex; flex-wrap: wrap; gap: 0.5rem; }
.interests li {
  border: 1px solid var(--rule); background: var(--surface); border-radius: 999px;
  padding: 0.2rem 0.85rem; font-size: 0.95rem;
}
.contact { margin: 0; }
.cta { margin-top: 2rem; }
.cta a { font-weight: 600; text-decoration: none; }
.cta a:hover { text-decoration: underline; }

/* ---------- Research ---------- */
.papers { list-style: none; margin: 0; padding: 0; max-width: 48rem; }
.paper { padding: 1.6rem 0; border-bottom: 1px solid var(--rule); }
.paper:first-child { padding-top: 0.25rem; }
.paper:last-child { border-bottom: 0; }
.paper-title { font-size: 1.3rem; margin: 0 0 0.35rem; }
.paper-title a { color: var(--text); text-decoration: none; }
.paper-title a:hover { color: var(--accent); text-decoration: underline; text-decoration-thickness: 1px; }
.paper-authors { margin: 0; color: var(--text); }
.paper-status { margin: 0.1rem 0 0; color: var(--muted); font-style: italic; }
.paper-status cite { font-style: italic; }
.paper-links { display: flex; flex-wrap: wrap; align-items: flex-start; gap: 0.6rem; margin-top: 0.85rem; }
.paper-actions {
  list-style: none; padding: 0; margin: 0; display: flex; flex-wrap: wrap; gap: 0.5rem 0.6rem; align-items: center;
}
.btn, .paper-abstract summary {
  display: inline-flex; align-items: center; gap: 0.35rem;
  font-size: 0.85rem; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase;
  color: var(--accent); background: var(--surface);
  border: 1px solid #d9d1c3; border-radius: 3px; padding: 0.3rem 0.7rem;
  text-decoration: none; cursor: pointer; line-height: 1.4;
}
.btn:hover, .paper-abstract summary:hover { border-color: var(--accent); color: var(--text); text-decoration: none; }
.btn .meta { font-weight: 400; text-transform: none; letter-spacing: 0; color: var(--muted); }
.paper-abstract { margin: 0; }
.paper-abstract[open] { flex-basis: 100%; }   /* open abstract takes the full row; buttons drop below it */
.paper-abstract summary { list-style: none; }
.paper-abstract summary::-webkit-details-marker { display: none; }
.paper-abstract summary::before {
  content: ""; flex: 0 0 auto; display: inline-block; width: 0.5em; height: 0.5em; border-right: 2px solid currentColor; border-bottom: 2px solid currentColor;
  transform: rotate(-45deg); margin-right: 0.25rem; transition: transform .15s ease;
}
.paper-abstract[open] summary::before { transform: translateY(-0.15em) rotate(45deg); }
.paper-abstract[open] summary { border-color: var(--accent); }
.paper-abstract p {
  margin: 0.9rem 0 0; padding: 0.1rem 0 0.1rem 1rem; border-left: 2px solid var(--rule);
  color: #34312c; font-size: 1rem; max-width: var(--measure);
}

/* ---------- Teaching ---------- */
.teaching-group { max-width: 48rem; }
.institution { font-size: 1.2rem; margin: 1.75rem 0 0.5rem; }
.section-title + .institution { margin-top: 0; }
.courses { list-style: none; margin: 0; padding: 0; }
.courses li {
  display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 0.25rem 1.5rem;
  padding: 0.55rem 0; border-bottom: 1px dotted var(--rule);
}
.courses li:last-child { border-bottom: 0; }
.course-name { font-weight: 400; }
.course-code { color: var(--muted); font-variant-numeric: tabular-nums; margin-right: 0.35rem; }
.course-terms { color: var(--muted); text-align: right; font-size: 0.95rem; }
.course-extra { grid-column: 1 / -1; margin-top: 0.25rem; }

/* ---------- CV ---------- */
.btn-lg { font-size: 0.95rem; padding: 0.55rem 1rem; }
.cv-embed { display: block; width: 100%; max-width: 52rem; height: 80vh; min-height: 36rem; margin-top: 2rem; border: 1px solid var(--rule); background: var(--surface); }
@media (max-width: 760px) { .cv-embed { display: none; } }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--rule); color: var(--muted); font-size: 0.9rem; }
.site-footer .inner {
  max-width: var(--wide); margin: 0 auto; padding: 1.5rem;
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: 0.5rem 1.5rem;
}
.site-footer p { margin: 0; }
.site-footer a { color: var(--muted); }

/* ---------- Responsive ---------- */
@media (max-width: 760px) {
  body { font-size: 1rem; }
  .site-header .inner { padding: 1.1rem 1.25rem; }
  .site-nav ul { gap: 1.25rem; }
  main { padding: 2.25rem 1.25rem 3.5rem; }
  .intro { grid-template-columns: 1fr; gap: 2rem; }
  .portrait { max-width: 13rem; }
  .courses li { grid-template-columns: 1fr; }
  .course-terms { text-align: left; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}

@media print {
  .site-header, .site-footer, .skip-link, .paper-actions { display: none; }
  .paper-abstract p { border: 0; padding: 0; }
  a { color: inherit; text-decoration: none; }
  body { background: #fff; }
}