/* ---------------------------------------------------------------
   Minimal academic site — Hau Pang (Eric) Chow
   Plain CSS, no build step. Edit colors in the :root block below.
----------------------------------------------------------------*/
:root {
  --maxw: 880px;
  --ink: #1d1d1f;
  --muted: #6b6b70;
  --rule: #e5e5e7;
  --link: #1a5fb4;
  --link-hover: #0b3d7a;
  --accent: #b4451a;            /* used sparingly for the name underline */
  --bg: #ffffff;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
        Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px 80px;
}

/* ---- top navigation ---- */
nav.site {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 22px 24px 16px;
  display: flex;
  flex-wrap: wrap;
  gap: 4px 22px;
  align-items: baseline;
  border-bottom: 1px solid var(--rule);
}
nav.site .brand {
  font-weight: 700;
  margin-right: auto;
  letter-spacing: .2px;
}
nav.site a {
  color: var(--muted);
  text-decoration: none;
  font-size: 15px;
}
nav.site a:hover { color: var(--ink); }
nav.site a.active { color: var(--ink); font-weight: 600; }

/* ---- header / hero on the home page ---- */
header.hero {
  display: flex;
  gap: 32px;
  align-items: flex-start;
  margin: 40px 0 8px;
}
header.hero .photo {
  flex: 0 0 180px;
}
header.hero .photo img {
  width: 180px; height: 180px;
  object-fit: cover;
  border-radius: 10px;
  border: 1px solid var(--rule);
  background: #f3f3f4;
}
header.hero h1 {
  font-size: 30px;
  line-height: 1.2;
  margin: 2px 0 4px;
}
header.hero h1 .alt { color: var(--muted); font-weight: 500; }
header.hero .role { color: var(--muted); margin: 0 0 12px; }

ul.links {
  list-style: none;
  padding: 0; margin: 10px 0 0;
  display: flex; flex-wrap: wrap;
  gap: 6px 16px;
  font-size: 15px;
}
ul.links a { color: var(--link); text-decoration: none; }
ul.links a:hover { color: var(--link-hover); text-decoration: underline; }
ul.links li::before { content: "·"; color: var(--rule); margin-right: 16px; }
ul.links li:first-child::before { content: ""; margin: 0; }

/* ---- page titles on inner pages ---- */
h1.page {
  font-size: 26px;
  margin: 40px 0 6px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}

h2.section {
  font-size: 17px;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--muted);
  margin: 38px 0 14px;
}

p { margin: 0 0 16px; }
a { color: var(--link); }
a:hover { color: var(--link-hover); }

/* ---- publication / paper list ---- */
ol.papers, ul.bare { list-style: none; padding: 0; margin: 0; }
.paper { margin: 0 0 26px; }
.paper .title { font-weight: 600; }
.paper .meta { color: var(--muted); font-size: 15px; margin: 2px 0 6px; }
.paper .paperlinks { font-size: 14.5px; }
.paper .paperlinks a { margin-right: 14px; }

/* abstract toggle */
details.abs { margin-top: 6px; }
details.abs > summary {
  cursor: pointer;
  color: var(--link);
  font-size: 14.5px;
  list-style: none;
  display: inline-block;
}
details.abs > summary::-webkit-details-marker { display: none; }
details.abs > summary::before { content: "▸ "; }
details.abs[open] > summary::before { content: "▾ "; }
details.abs > summary:hover { color: var(--link-hover); }
details.abs .body {
  margin-top: 8px;
  padding: 12px 16px;
  background: #fafafb;
  border: 1px solid var(--rule);
  border-radius: 8px;
  font-size: 15px;
  color: #2b2b2f;
}

/* ---- news ---- */
ul.news { list-style: none; padding: 0; margin: 0; font-size: 15.5px; }
ul.news li { margin: 0 0 8px; }
ul.news .when { color: var(--muted); font-variant-numeric: tabular-nums; margin-right: 8px; }

/* ---- teaching ---- */
table.teach { border-collapse: collapse; width: 100%; font-size: 15px; }
table.teach td { padding: 8px 12px 8px 0; border-bottom: 1px solid var(--rule); vertical-align: top; }
table.teach td.term { color: var(--muted); white-space: nowrap; width: 1%; padding-right: 20px; }
table.teach td.role { color: var(--muted); white-space: nowrap; width: 1%; padding-right: 20px; }

/* ---- footer ---- */
footer.site {
  margin-top: 56px;
  padding-top: 16px;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: 13.5px;
}

/* ---- small screens ---- */
@media (max-width: 560px) {
  header.hero { flex-direction: column; gap: 18px; }
  header.hero .photo, header.hero .photo img { flex: none; width: 140px; height: 140px; }
  nav.site { gap: 4px 16px; }
}