/* Personal site: one quiet column, set like a paper. No external fonts
   (fast, and no third-party requests from a university page). */

:root {
  --paper: #ffffff;
  --ink: #1d2327;
  --muted: #5b666c;
  --rule: #d9dee1;
  --accent: #1d5a4b;       /* blackboard green */
  --accent-soft: #e8f1ed;
  --warn: #8c3a12;
  --warn-soft: #fbeee5;
  --measure: 42rem;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #161a19;
    --ink: #e2e6e3;
    --muted: #98a39e;
    --rule: #2d3432;
    --accent: #82c7ad;
    --accent-soft: #1c2a25;
    --warn: #f1a878;
    --warn-soft: #2c211a;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Charter, "Bitstream Charter", "Sitka Text", Cambria, "Noto Serif", Georgia, serif;
  font-size: 1.0625rem;
  line-height: 1.6;
  -webkit-text-size-adjust: 100%;
}

.site-header, main, footer {
  max-width: var(--measure);
  margin-inline: auto;
  padding-inline: 1.25rem;
}

/* Header: the name set in small capitals, like an author line on a paper. */
.site-header { padding-top: clamp(2rem, 7vw, 4rem); }

.site-name {
  margin: 0;
  font-size: clamp(2rem, 6vw, 2.75rem);
  font-variant: small-caps;
  letter-spacing: 0.03em;
  line-height: 1.1;
}
.site-name a { color: inherit; text-decoration: none; }

.site-affil {
  margin: 0.4rem 0 0;
  color: var(--muted);
  font-style: italic;
}

nav {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  margin-top: 1.75rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--rule);
}
nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.25rem;
  margin: 0;
  padding: 0;
  list-style: none;
}
nav a { color: var(--ink); text-decoration: none; }
nav a:hover { color: var(--accent); }
nav a[aria-current="page"] {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 0.4em;
}
nav .lang { color: var(--muted); font-size: 0.9375rem; }

main { padding-top: 2rem; padding-bottom: 3rem; }

h1 { margin: 0 0 1.5rem; font-size: 1.625rem; font-weight: 400; line-height: 1.25; }
h2 { margin: 2.5rem 0 1rem; font-size: 1.125rem; font-weight: 700; color: var(--accent); }
main > h2:first-child, h1 + h2 { margin-top: 0; }

a { color: var(--accent); text-underline-offset: 0.15em; }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 2px; }

address { font-style: normal; }

/* Publications */
.profiles { margin: 0 0 2rem; }

.pubs { margin: 0; padding: 0; list-style: none; }
.pub { position: relative; margin: 0 0 1.1rem; }
.pub cite { font-style: italic; }
.pub-year {
  display: block;
  color: var(--muted);
  font-size: 0.875rem;
  font-variant-numeric: oldstyle-nums;
}
.pub-links { white-space: nowrap; }

/* On wide screens the year hangs in the left margin. */
@media (min-width: 56rem) {
  .pub-year {
    position: absolute;
    left: -4.5rem;
    width: 3.5rem;
    top: 0.1em;
    text-align: right;
    font-size: 1rem;
  }
}

.note {
  margin: 0.5rem 0 0;
  padding: 0.5rem 0.8rem;
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  font-size: 0.9375rem;
}
.note.erratum { border-left-color: var(--warn); background: var(--warn-soft); }
.note.erratum a { color: var(--warn); }

footer { color: var(--muted); font-size: 0.875rem; padding-bottom: 3rem; }
footer p { margin: 0; padding-top: 1rem; border-top: 1px solid var(--rule); }

/* Teaching: one collapsible block per academic year. */
.intro { color: var(--muted); font-style: italic; }
details.year { border-top: 1px solid var(--rule); }
details.year:last-of-type { border-bottom: 1px solid var(--rule); }
details.year > summary {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  padding: 0.6rem 0;
  cursor: pointer;
  list-style: none;
}
details.year > summary::-webkit-details-marker { display: none; }
details.year > summary::before {
  content: "";
  flex: none;
  width: 0.45em;
  height: 0.45em;
  border-right: 2px solid var(--muted);
  border-bottom: 2px solid var(--muted);
  transform: translateY(-0.15em) rotate(-45deg);
  transition: transform 0.15s;
}
details.year[open] > summary::before { transform: translateY(-0.3em) rotate(45deg); }
details.year > summary h2 { margin: 0; font-variant-numeric: lining-nums; }
details.year > summary:hover h2 { text-decoration: underline; text-underline-offset: 0.2em; }
.courses { margin: 0 0 1.25rem; padding: 0; list-style: none; }
.courses li { margin: 0 0 0.9rem; }
.courses p { margin: 0; }
.courses .docs { font-size: 0.9375rem; color: var(--muted); }
@media (prefers-reduced-motion: reduce) { details.year > summary::before { transition: none; } }


/* Header: a real blackboard (a frame from one of my lectures, tinted and faded). */
:root {
  --band: #1f4a40;
  --band-edge: #173a32;
  --band-ink: #f2f0e8;
  --band-muted: #c3d6cd;
  --chalk: #e9d98f;
  --band-shade: rgba(0, 0, 0, 0);
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) { --band-edge: #10302a; --band-shade: rgba(0, 0, 0, 0.3); --chalk: #e0cf7c; }
}
:root[data-theme="dark"] { --band-edge: #10302a; --band-shade: rgba(0, 0, 0, 0.3); --chalk: #e0cf7c; }

.board {
  background:
    linear-gradient(var(--band-shade), var(--band-shade)),
    linear-gradient(90deg, rgba(31, 74, 64, 0.55), rgba(31, 74, 64, 0) 60%),
    url("tableau.jpg") center 30% / cover,
    var(--band);
  border-bottom: 5px solid var(--band-edge);
  color: var(--band-ink);
}
.board .site-header { padding-bottom: 0.9rem; }
.board .site-name a { color: var(--band-ink); text-shadow: 0 0 2px rgba(242, 240, 232, 0.35), 0 1px 8px rgba(20, 50, 43, 0.8); }
.board .site-affil { color: var(--band-muted); text-shadow: 0 1px 6px rgba(20, 50, 43, 0.9); }
.board nav { border-bottom: 0; padding-bottom: 0; margin-top: 1.5rem; }
.board nav a { color: var(--band-ink); text-shadow: 0 1px 6px rgba(20, 50, 43, 0.9); }
.board nav a:hover { color: var(--chalk); }
.board nav a[aria-current="page"] { color: var(--chalk); text-decoration-color: var(--chalk); }
.board nav .lang { color: var(--band-muted); }
.board a:focus-visible { outline-color: var(--chalk); }
main { padding-top: 2.5rem; }