/* ==========================================================================
   Wei Jiang — academic homepage
   A single stylesheet, no framework, no build step.
   ========================================================================== */

:root {
  color-scheme: light dark;

  --paper: #fbfcfa;
  --paper-blur: rgba(251, 252, 250, 0.86);
  --surface: #f1f5f2;
  --ink: #18201f;
  --body: #2f3836;
  --muted: #626a68;
  --line: #d8dedb;

  --accent: #006b68;
  --accent-dark: #12403e;
  --accent-tint: rgba(0, 107, 104, 0.08);
  --accent-line: rgba(0, 107, 104, 0.3);

  --warm: #a83f2c;
  --warm-tint: rgba(189, 75, 55, 0.1);
  --gold-ink: #7d5a12;
  --gold-tint: rgba(213, 166, 66, 0.18);

  --serif: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Palatino, Georgia, "Times New Roman", serif;
  --sans: "Inter", ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --topbar-h: 4.25rem;
  --maxw: 1180px;
  --measure: 46rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #101413;
    --paper-blur: rgba(16, 20, 19, 0.82);
    --surface: #171d1c;
    --ink: #e7ece9;
    --body: #cfd7d4;
    --muted: #98a3a0;
    --line: #272f2d;

    --accent: #4ec2b6;
    --accent-dark: #93dbd2;
    --accent-tint: rgba(78, 194, 182, 0.12);
    --accent-line: rgba(78, 194, 182, 0.34);

    --warm: #e08571;
    --warm-tint: rgba(224, 133, 113, 0.14);
    --gold-ink: #dcb96c;
    --gold-tint: rgba(220, 185, 108, 0.14);
  }
}

/* --------------------------------------------------------------- base --- */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--topbar-h) + 1.75rem);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--body);
  font-family: var(--sans);
  font-size: 1.02rem;
  line-height: 1.68;
  letter-spacing: -0.004em;
  overflow-wrap: break-word;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4 {
  color: var(--ink);
  font-weight: 600;
}

p {
  margin: 0 0 1rem;
}

p:last-child {
  margin-bottom: 0;
}

a {
  color: var(--accent);
  text-decoration: none;
  text-underline-offset: 0.18em;
  text-decoration-thickness: 1px;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

a:hover {
  color: var(--accent-dark);
}

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

hr {
  border: 0;
}

.icon-sprite {
  display: none;
}

.icon {
  width: 0.92em;
  height: 0.92em;
  flex: none;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 50;
  padding: 0.6rem 1rem;
  background: var(--ink);
  color: var(--paper);
  border-radius: 0 0 8px 0;
  font-size: 0.85rem;
}

.skip-link:focus {
  left: 0;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 3px;
}

/* -------------------------------------------------------------- topbar --- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: var(--paper-blur);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}

.topbar-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  height: var(--topbar-h);
  padding: 0 clamp(1.25rem, 4vw, 2.75rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--ink);
  flex: none;
  min-width: 0;
}

.brand:hover {
  color: var(--ink);
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 1.95rem;
  height: 1.95rem;
  border-radius: 7px;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--serif);
  font-size: 0.76rem;
  letter-spacing: 0.06em;
}

.brand-name {
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: -0.005em;
}

.nav {
  display: flex;
  align-items: center;
  gap: clamp(0.85rem, 1.9vw, 1.5rem);
  min-width: 0;          /* lets the row shrink instead of widening the page */
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.nav::-webkit-scrollbar {
  display: none;
}

.nav a {
  position: relative;
  padding: 0.35rem 0;
  color: var(--muted);
  font-size: 0.83rem;
  white-space: nowrap;
}

.nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0.1rem;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.24s ease;
}

.nav a:hover,
.nav a.is-active {
  color: var(--ink);
}

.nav a:hover::after,
.nav a.is-active::after {
  transform: scaleX(1);
}

/* ---------------------------------------------------------------- page --- */

.page {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(2rem, 4vw, 3rem) clamp(1.25rem, 4vw, 2.75rem) 4rem;
  display: grid;
  grid-template-columns: minmax(0, 15.5rem) minmax(0, 1fr);
  gap: clamp(2.5rem, 5vw, 4.5rem);
  align-items: start;
}

.page--narrow {
  display: block;
  max-width: 40rem;
}

/* ------------------------------------------------------------- profile --- */

.profile {
  position: sticky;
  top: calc(var(--topbar-h) + 2rem);
  min-width: 0;
}

.avatar {
  display: block;
  width: min(100%, 13.5rem);
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: var(--surface);
}

.eyebrow {
  margin: 1.6rem 0 0.45rem;
  color: var(--muted);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.profile-name {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(1.6rem, 3.2vw, 1.9rem);
  font-weight: 500;
  line-height: 1.15;
  letter-spacing: -0.012em;
}

.profile-headline {
  margin: 0.55rem 0 0;
  color: var(--ink);
  font-size: 0.95rem;
  font-weight: 600;
  line-height: 1.45;
}

.profile-meta {
  margin: 0.5rem 0 0;
  color: var(--muted);
  font-size: 0.875rem;
  line-height: 1.55;
}

.rule {
  margin: 1.4rem 0 1.15rem;
  border-top: 1px solid var(--line);
}

.links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.6rem 0.9rem;
}

.links a {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  color: var(--ink);
  font-size: 0.82rem;
  min-width: 0;
}

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

.links .icon {
  color: var(--muted);
}

.links a:hover .icon {
  color: var(--accent);
}

.links a span {
  border-bottom: 1px solid var(--line);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.links a:hover span {
  border-bottom-color: currentColor;
}

/* ------------------------------------------------------------- content --- */

.content {
  min-width: 0;
  max-width: var(--measure);
}

.page-title {
  margin: 0 0 1.15rem;
  font-family: var(--serif);
  font-size: clamp(2rem, 4.6vw, 2.6rem);
  font-weight: 500;
  line-height: 1.08;
  letter-spacing: -0.018em;
}

.lead {
  color: var(--body);
  font-size: 1.02rem;
}

.lead + .lead {
  margin-top: 1rem;
}

.section {
  margin-top: clamp(2.5rem, 4.5vw, 3.5rem);
}

/* The first section sits flush with the top of the portrait. */
.section-about {
  margin-top: 0;
}

.section-head {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: 1.15rem 0 0.95rem;
}

.section-num {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
}

.section-title {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(1.4rem, 3vw, 1.62rem);
  font-weight: 500;
  letter-spacing: -0.012em;
}

/* -------------------------------------------------------- publications --- */

.pub-group + .pub-group {
  margin-top: 1.9rem;
}

.pub-group-title {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin: 0;
  padding-top: 1.2rem;
  color: var(--ink);
  font-size: 0.94rem;
  font-weight: 600;
  letter-spacing: -0.005em;
}

.pub-group-title::before {
  content: "";
  flex: none;
  width: 2px;
  height: 1em;
  border-radius: 1px;
  background: var(--accent);
}

.pub-group + .pub-group .pub-group-title {
  border-top: 1px solid var(--line);
}

.pub-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.pub {
  display: grid;
  grid-template-columns: 3.1rem minmax(0, 1fr);
  gap: 1.25rem;
  padding: 1.15rem 0;
  border-bottom: 1px solid var(--line);
}

.pub-year {
  margin: 0.1rem 0 0;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.02em;
}

.pub-title {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.45;
}

.pub-authors {
  margin: 0.4rem 0 0;
  color: var(--body);
  font-size: 0.88rem;
}

.pub-authors strong {
  color: var(--ink);
  font-weight: 600;
}

.pub-venue {
  margin: 0.35rem 0 0;
  color: var(--muted);
  font-size: 0.87rem;
}

.pub-venue-name {
  font-style: italic;
}

.tag {
  display: inline-block;
  margin-left: 0.45rem;
  padding: 0.06rem 0.45rem;
  border: 1px solid transparent;
  border-radius: 999px;
  background: var(--surface);
  color: var(--muted);
  font-size: 0.66rem;
  font-weight: 600;
  font-style: normal;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  vertical-align: 0.08em;
  white-space: nowrap;
}

.tag--ccf-a {
  background: var(--accent-tint);
  color: var(--accent);
}

.tag--oral {
  background: var(--warm-tint);
  color: var(--warm);
}

.tag--preprint {
  background: var(--gold-tint);
  color: var(--gold-ink);
}

.pub-note {
  margin: 0.55rem 0 0;
  padding-left: 0.75rem;
  border-left: 2px solid var(--accent-line);
  color: var(--muted);
  font-size: 0.87rem;
  line-height: 1.62;
}

.pub-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0.6rem 0 0;
}

.pill {
  display: inline-block;
  padding: 0.14rem 0.6rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  color: var(--ink);
  font-size: 0.74rem;
  letter-spacing: 0.01em;
}

.pill:hover {
  border-color: var(--accent-line);
  background: var(--accent-tint);
  color: var(--accent);
}

/* ------------------------------------------------- entries (cv lists) --- */

.entries {
  list-style: none;
  margin: 0;
  padding: 0;
}

.entry {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1.5rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--line);
}

.entry-main {
  min-width: 0;
}

.entry-title {
  margin: 0;
  font-size: 0.98rem;
  font-weight: 600;
  line-height: 1.4;
}

.entry-subtitle {
  margin: 0.2rem 0 0;
  color: var(--muted);
  font-size: 0.89rem;
}

.entry-note {
  margin: 0.5rem 0 0;
  max-width: 34rem;
  color: var(--muted);
  font-size: 0.86rem;
  line-height: 1.62;
}

.entry-period {
  flex: none;
  margin: 0;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.77rem;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

/* ------------------------------------------------------------- service --- */

.service {
  margin: 0;
}

.service-row {
  display: grid;
  grid-template-columns: 7.5rem minmax(0, 1fr);
  gap: 1.5rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--line);
}

.service-label {
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  padding-top: 0.34rem;
}

.service-items {
  margin: 0;
}

.service-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.service-item {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 0.17rem 0;
}

.service-name {
  font-size: 0.89rem;
  line-height: 1.5;
}

.service-years {
  flex: none;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.76rem;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

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

.footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.5rem 1rem;
  margin-top: clamp(2.5rem, 4.5vw, 3.5rem);
  padding-top: 1.2rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.8rem;
}

.footer-note {
  font-family: var(--mono);
  font-size: 0.74rem;
}

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

@media (max-width: 900px) {
  .page {
    grid-template-columns: minmax(0, 1fr);
    gap: 2.5rem;
    padding-top: 2rem;
  }

  .content {
    max-width: none;
  }

  .profile {
    position: static;
    display: grid;
    grid-template-columns: minmax(0, 8rem) minmax(0, 1fr);
    grid-template-areas:
      "avatar eyebrow"
      "avatar name"
      "avatar headline"
      "avatar meta"
      "rule rule"
      "links links";
    column-gap: 1.5rem;
    align-items: start;
  }

  .avatar  { grid-area: avatar; width: 100%; }
  .eyebrow { grid-area: eyebrow; margin-top: 0.1rem; }
  .profile-name     { grid-area: name; }
  .profile-headline { grid-area: headline; }
  .profile-meta     { grid-area: meta; }
  .rule  { grid-area: rule; }
  .links { grid-area: links; }
}

@media (max-width: 620px) {
  :root {
    --topbar-h: 0rem;
  }

  html {
    scroll-padding-top: 1rem;
  }

  body {
    font-size: 1rem;
  }

  /* The header scrolls away on small screens so that it does not eat the
     viewport; the navigation stays available at the top of the page. */
  .topbar {
    position: static;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    background: var(--paper);
  }

  .topbar-inner {
    height: auto;
    flex-wrap: wrap;
    row-gap: 0.45rem;
    padding-top: 0.7rem;
    padding-bottom: 0.65rem;
  }

  .nav {
    width: 100%;
    flex-wrap: wrap;
    justify-content: flex-start;
    column-gap: 1rem;
    row-gap: 0.1rem;
    overflow-x: visible;
  }

  .nav a {
    font-size: 0.81rem;
  }

  .pub {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.4rem;
  }

  .pub-year {
    margin: 0;
  }

  .entry {
    flex-direction: column;
    gap: 0.35rem;
  }

  .entry-period {
    order: -1;
  }

  .service-row {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.5rem;
  }

  .service-item {
    flex-wrap: wrap;
    gap: 0 1rem;
  }
}

/* --------------------------------------------------------------- print --- */

@media print {
  :root {
    --paper: #fff;
    --topbar-h: 0rem;
  }

  body {
    font-size: 10.5pt;
  }

  .topbar,
  .skip-link,
  .pub-links,
  .footer-note {
    display: none;
  }

  .page {
    display: block;
    max-width: none;
    padding: 0;
  }

  .profile {
    position: static;
    display: block;
    margin-bottom: 1.5rem;
  }

  .avatar {
    width: 3.5rem;
    border-radius: 6px;
  }

  .eyebrow,
  .rule,
  .links {
    display: none;
  }

  .content {
    max-width: none;
  }

  .section {
    margin-top: 1.75rem;
  }

  .pub,
  .entry,
  .service-row {
    break-inside: avoid;
    page-break-inside: avoid;
  }

  a {
    color: inherit;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }
}