:root {
  --bg: #ffffff;
  --text: #111111;
  --muted: #666666;
  --link: #0645ad;
  --border: #e5e5e5;
  --content-width: 920px;
  --sidebar-width: 200px;
  --radius: 6px;
  --space: 16px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0b0b;
    --text: #eaeaea;
    --muted: #b3b3b3;
    --link: #4da3ff;
    --border: #222222;
  }
}

* { box-sizing: border-box; }
html {
  scroll-behavior: smooth;
}
body {
  margin: 0;
  font: 16px/1.6 system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, Helvetica, Arial,
    "Apple Color Emoji", "Segoe UI Emoji";
  color: var(--text);
  background: var(--bg);
}

a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }


.wrap {
  width: 100%;
  margin: 0 auto;
  padding: 0 clamp(0px, 7vw, 120px);
  max-width: calc(160px + var(--content-width) + 200px);
  display: grid;
  grid-template-columns: auto minmax(0, var(--content-width));
  justify-content: center;
  align-items: start;
  column-gap: 0px;
}


.sidebar {
  grid-column: 1;
  justify-self: end;
  width: 120px;
  position: sticky;
  top: 50%;
  transform: translateY(-50%);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
}

nav {
  width: 100%;
  text-align: left;
}

nav .name {
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: 8px;
}

nav ul {
  list-style: none;
  padding: 0;
  margin: 8px 0 0 0;
}

nav li { margin: 6px 0; }
nav a { color: var(--text); }

main {
  grid-column: 2;
  max-width: var(--content-width);
}

header.hero {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  margin: 0;
  padding: 12px; /* add some breathing room for small viewports */
  border: 0;
  color: var(--text);
  /* removed internal scrolling so the main page scrollbar is used */
  /* overflow-y: auto; */
}

/* Layout inside the hero: left content + right profile photo */
.hero-card {
  max-width: var(--content-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding: 0 12px;
  /* allow the card to grow naturally; remove internal max-height/overflow */
  /* max-height: calc(100svh - 24px);
  overflow: auto; */
}

/* top row: name and photo side-by-side */
.hero-top {
  display: flex;
  align-items: center;
  gap: 20px;
  width: 100%;
  flex-wrap: wrap; /* allow items to wrap instead of overflowing on narrow widths */
}

/* name block */
.name-block { 
  display: flex;
  flex-direction: column;
  justify-content: center;
  text-align: left;
}

.name-zh {
  font-size: 2rem;
  margin: 0;
  line-height: 1;
  font-weight: 700;
}

.name-en {
  font-size: 1rem;
  margin-top: 6px;
  color: var(--muted);
}

/* keep photo sizing consistent and responsive */
.hero-photo {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
}

.profile {
  /* width: 160px;
  height: 120px; */ /* removed fixed height */
  width: clamp(100px, 18vw, 160px);
  height: auto;
  max-height: 30vh;
  object-fit: cover;
  border-radius: 8px;
  border: 2px solid var(--border);
  display: block;
}

header.hero h1 {
  font-size: 1.8rem;
  margin: 0 0 8px 0;
  line-height: 1.2;
}

header.hero p {
  margin: 0.35rem 0;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}

.tag {
  border: 1px solid var(--border);
  padding: 2px 8px;
  border-radius: var(--radius);
  font-size: 0.85rem;
  color: var(--muted);
}

section {
  margin: 32px 0;
}

/* place the separator explicitly after the about/hero section */
header.hero + section {
  border-top: 1px solid var(--border);
  padding-top: 16px;
}

section h2 {
  /* larger, more prominent section titles (increased) */
  font-size: 1.75rem; /* was 1.4rem */
  margin: 0 0 10px 0;
  letter-spacing: 0.2px;
  font-weight: 800;
}

/* increase spacing between items more */
.item { 
  margin: 32px 0; /* increased to give clearer separation between items */
}

/* tighten spacing inside each item: paragraphs and lists closer together */
.item p,
.item ul,
.item ol {
  margin: 0.28rem 0; /* smaller than browser default */
}

.item li {
  margin: 0.25rem 0; /* tighter list items */
}

/* small adjustment for item header and meta spacing */
.item > div:first-child {
  margin-bottom: 6px;
}
.item .meta {
  margin: 6px 0 8px;
  color: var(--muted);
  font-size: 0.95rem;
}

/* Make the item header larger but not fully bold;
   keep only the <strong> title bold so trailing text (— Prof...) is normal weight. */
.item > div:first-child {
  font-size: 1.15rem;
  font-weight: 400; /* normal weight for the whole header */
  color: var(--text);
  margin-bottom: 6px; /* small gap before meta / body */
}
.item > div:first-child strong {
  font-weight: 700; /* only the strong text is bold */
}

/* keep sizes comfortable on small screens */
@media (max-width: 600px) {
  section h2 { font-size: 1.4rem; }
  .item > div:first-child { font-size: 1.02rem; }
  .item { margin: 32px 0; } /* slightly smaller separation on small screens */
}

/* small highlighted note for announcements / links in sections */
.note {
  border-left: 4px solid var(--link);
  background: rgba(0,0,0,0.03);
  padding: 10px 12px;
  border-radius: 6px;
  margin: 8px 0 16px;
  color: var(--text);
  font-size: 0.98rem;
}
.note a { color: var(--link); font-weight: 600; text-decoration: none; }
.note a:hover { text-decoration: underline; }

.figure {
  text-align: center;
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 0.95rem;
}
.figure img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 8px auto;
  border-radius: 6px;
  border: 1px solid var(--border);
}
.figure figcaption {
  margin-top: 6px;
  color: var(--muted);
  font-size: 0.9rem;
}

/* horizontal figure: ensure images and embeds sit side-by-side; allow inline widths */
.figure-horizontal {
  display: flex;
  gap: 12px;
  justify-content: center;
  align-items: center; /* center images/iframe vertically */
  flex-wrap: wrap;
  margin-top: 12px;
}

/* ensure each direct child centers itself in the cross axis */
.figure-horizontal > * {
  align-self: center;
}

/* Ensure figcaption always appears on its own line below the images */
.figure-horizontal figcaption {
  flex: 0 0 100%;
  order: 2;
  margin-top: 8px;
  text-align: center;
  color: var(--muted);
  font-size: 0.9rem;
}

/* mobile: stack vertically */
@media (max-width: 700px) {
  .figure-horizontal img {
    width: 100%;
    max-width: 100%;
  }
  .figure-horizontal iframe {
    width: 100% !important;
    height: auto;
  }
}

.list { padding-left: 1.1rem; }
hr { border: none; border-top: 1px solid var(--border); margin: 24px 0; }

footer {
  margin: 48px 0 24px;
  color: var(--muted);
  font-size: 0.9rem;
}

.contact a { margin-right: 12px; }

.skip {
  position: absolute;
  left: -9999px;
}

.skip:focus {
  left: 12px;
  top: 12px;
  background: var(--bg);
  color: var(--text);
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  z-index: 2;
}

.sidebar-toggle {
  display: none;
  align-self: flex-start;
  z-index: 80;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 6px 10px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 0.95rem;
  line-height: 1;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}
.sidebar-toggle:focus {
  outline: 2px solid var(--link);
  outline-offset: 2px;
}

@media (max-width: 700px) {
  .wrap {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    max-width: none;
    gap: 12px;
  }

  .sidebar {
    width: 100%;
    position: static;
    transform: none;
    flex-direction: column;
    gap: 0;
  }

  main {
    width: 100%;
    max-width: none;
  }

  #sidebar {
    display: none;
    position: fixed;
    top: 56px;
    left: 12px;
    right: auto;
    width: min(220px, calc(100vw - 60px));
    background: var(--bg);
    padding: 10px 12px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
    text-align: left;
    max-height: calc(100vh - 88px);
    overflow-y: auto;
    z-index: 70;
  }

  .sidebar-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    position: fixed;
    top: 12px;
    left: 12px;
  }

  body.sidebar-visible #sidebar {
    display: block;
  }
}