/* ---------- Tokens ---------- */
:root {
  --bg: #f5f2eb;
  --paper: #fbf8f1;
  --ink: #0e1410;
  --ink-soft: #2c332e;
  --muted: #7a7e78;
  --rule: rgba(14, 20, 16, 0.18);
  --rule-soft: rgba(14, 20, 16, 0.10);
  --accent: #14b8a6;

  --font-display: "Source Serif 4", "Times New Roman", serif;
  --font-body: "Inter", system-ui, sans-serif;

  --max: 1320px;
  --gutter: clamp(20px, 5vw, 64px);
}

* { box-sizing: border-box; }
html {
  scroll-behavior: smooth;
}
body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

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

/* Top accent stripe — sets the tone immediately */
body::before {
  content: "";
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent) 0%, #2dd4bf 60%, var(--accent) 100%);
  z-index: 100;
}

/* ---------- Nav ---------- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px var(--gutter);
  background: rgba(245, 242, 235, 0.85);
  backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid var(--rule-soft);
}
.nav-mark {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 500;
  letter-spacing: -0.005em;
}
.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
  margin: 0; padding: 0;
  font-size: 14px;
  font-weight: 400;
}
.nav-links a {
  position: relative;
  padding-bottom: 4px;
  transition: color 0.25s;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0; right: 100%;
  bottom: 0;
  height: 1px;
  background: var(--ink);
  transition: right 0.3s ease;
}
.nav-links a:hover::after,
.nav-links a.is-active::after { right: 0; }
@media (max-width: 760px) {
  .nav-links { gap: 18px; font-size: 13px; }
}

/* ---------- Hero (front = about) ---------- */
.hero {
  position: relative;
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(110px, 12vh, 140px) clamp(32px, 8vw, 120px) clamp(48px, 6vw, 80px);
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: clamp(40px, 6vw, 88px);
  align-items: start;
}
@media (max-width: 880px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

.hero-label {
  margin: 0 0 24px;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
}

.hero-name {
  font-family: var(--font-display);
  font-weight: 500;
  font-variation-settings: "opsz" 60;
  font-size: clamp(40px, 5.4vw, 72px);
  line-height: 1;
  letter-spacing: -0.024em;
  margin: 0 0 32px;
  color: var(--ink);
}
.hero-name em {
  font-style: normal;
  font-weight: 500;
  color: var(--ink);
}

.hero-tag {
  margin: 0 0 28px;
  font-family: var(--font-display);
  font-size: clamp(16px, 1.4vw, 19px);
  color: var(--ink-soft);
}
.hero-tag em {
  font-style: italic;
  color: var(--accent);
}

.hero-prose {
  margin-bottom: 8px;
}
.hero-prose p {
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 15px;
  line-height: 1.72;
  color: var(--ink-soft);
  margin: 0 0 18px;
  max-width: none;
}
.hero-prose a {
  color: var(--ink);
  border-bottom: 1px solid rgba(20, 184, 166, 0.45);
  padding-bottom: 1px;
  transition: color 0.25s, border-color 0.25s;
}
.hero-prose a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}
.hero-prose em {
  font-style: italic;
  color: var(--ink);
}

/* ---------- Collaboration (full-bleed teal) ---------- */
.collab {
  position: relative;
  background: var(--accent);
  color: #fff;
  overflow: hidden;
}
.collab::before {
  content: "";
  position: absolute;
  top: -200px; right: -120px;
  width: 520px; height: 520px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.18), transparent 60%);
  pointer-events: none;
}
.collab::after {
  content: "";
  position: absolute;
  bottom: -160px; left: -120px;
  width: 460px; height: 460px;
  background: radial-gradient(circle, rgba(13, 148, 136, 0.55), transparent 65%);
  pointer-events: none;
}
.collab-inner {
  position: relative;
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(40px, 5vw, 64px) var(--gutter);
}
.collab-label {
  margin: 0 0 14px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.85);
}
.collab-headline {
  font-family: var(--font-display);
  font-weight: 400;
  font-variation-settings: "opsz" 60;
  font-size: clamp(28px, 3.6vw, 44px);
  line-height: 1.05;
  letter-spacing: -0.022em;
  margin: 0 0 16px;
  color: #fff;
  max-width: 18ch;
}
.collab-headline em {
  font-style: italic;
  font-weight: 400;
  color: #ccfbf1;
}
.collab-line {
  font-family: var(--font-display);
  font-size: clamp(17px, 1.6vw, 20px);
  line-height: 1.55;
  color: rgba(255, 255, 255, 0.92);
  margin: 0 0 26px;
  max-width: 60ch;
}
.collab-email {
  color: #fff;
  border-bottom: 1px solid rgba(255, 255, 255, 0.5);
  padding-bottom: 1px;
  transition: border-color 0.25s, color 0.25s;
}
.collab-email:hover {
  border-color: #fff;
  color: #ccfbf1;
}

/* ---------- Socials (used in collab section) ---------- */
.socials {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 14px;
}
.socials a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: 999px;
  color: #fff;
  background: transparent;
  transition: color 0.25s, border-color 0.25s, transform 0.25s, background 0.25s, box-shadow 0.25s;
}
.socials a svg {
  width: 18px;
  height: 18px;
}
.socials a:hover {
  color: var(--accent);
  border-color: #fff;
  background: #fff;
  transform: translateY(-3px);
  box-shadow: 0 14px 30px -10px rgba(0, 0, 0, 0.25);
}
.socials-large a {
  width: 42px;
  height: 42px;
}
.socials-large a svg {
  width: 16px;
  height: 16px;
}

/* ---------- Hero photo (single, auto-cycling) ---------- */
.hero-photo {
  position: relative;
  margin: 0 0 0 auto;
  aspect-ratio: 4 / 5;
  width: auto;
  max-width: 100%;
  background: var(--paper);
  overflow: hidden;
  border-radius: 2px;
}
@media (max-width: 880px) {
  .hero-photo { width: 100%; margin: 0; }
}
.hp-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0;
  transition: opacity 1.1s cubic-bezier(.22,.6,.36,1);
  filter: saturate(0.94) contrast(1.02);
  will-change: opacity;
}
.hp-img.is-active { opacity: 1; }

/* ---------- Divider ---------- */
.divider {
  border: 0;
  border-top: 1px solid var(--rule);
  max-width: var(--max);
  margin: 0 auto;
  width: calc(100% - 2 * var(--gutter));
}

/* ---------- Section base ---------- */
.section {
  position: relative;
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(64px, 8vw, 112px) var(--gutter);
}
.section-grid {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: clamp(32px, 6vw, 96px);
  align-items: start;
}
@media (max-width: 880px) {
  .section-grid { grid-template-columns: 1fr; gap: 32px; }
}

.section-aside {
  position: sticky;
  top: 120px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
@media (max-width: 880px) {
  .section-aside { position: static; flex-direction: row; gap: 14px; }
}
.section-num {
  font-family: var(--font-display);
  font-style: italic;
  font-size: clamp(38px, 4.4vw, 56px);
  font-weight: 400;
  line-height: 0.9;
  margin: 0;
  color: var(--accent);
  letter-spacing: -0.018em;
}
.section-label {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
  margin: 8px 0 0;
}
@media (max-width: 880px) {
  .section-num { font-size: 32px; }
  .section-label { margin-top: 0; }
}

.section-headline {
  font-family: var(--font-display);
  font-weight: 400;
  font-variation-settings: "opsz" 60;
  font-size: clamp(28px, 3.6vw, 52px);
  line-height: 1.05;
  letter-spacing: -0.02em;
  margin: 0 0 20px;
  color: var(--ink);
  max-width: 20ch;
}
.section-headline em {
  font-style: italic;
  font-weight: 400;
  color: var(--accent);
}
.section-sub {
  margin: 0 0 16px;
  color: var(--ink-soft);
  max-width: 60ch;
  font-size: 15px;
  line-height: 1.6;
}

.papers-note {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  margin: 0 0 36px;
  padding: 10px 16px 11px;
  background: rgba(20, 184, 166, 0.09);
  border-left: 2px solid var(--accent);
  border-radius: 0 4px 4px 0;
  font-size: 13px;
  color: var(--ink-soft);
  line-height: 1.5;
}
.papers-note-mark {
  font-family: var(--font-display);
  font-style: italic;
  color: var(--accent);
  font-weight: 600;
  font-size: 20px;
  line-height: 1;
  position: relative;
  top: 2px;
}

/* ---------- Prose ---------- */
.prose {
  max-width: 60ch;
}
.prose p {
  font-size: 17px;
  line-height: 1.72;
  margin: 0 0 24px;
  color: var(--ink-soft);
}
.prose .lead {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(20px, 2vw, 24px);
  line-height: 1.45;
  color: var(--ink);
  margin-bottom: 32px;
  max-width: 30ch;
}
.prose strong { color: var(--ink); font-weight: 600; }

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 24px;
  font-size: 16px;
  font-weight: 500;
  color: var(--ink);
  border-bottom: 1px solid var(--ink);
  padding-bottom: 4px;
  transition: color 0.25s, border-color 0.25s, transform 0.25s;
}
.link-arrow:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* ---------- Research ---------- */
.papers {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--rule);
}
.paper {
  position: relative;
  display: grid;
  grid-template-columns: 1fr minmax(160px, 220px);
  gap: 28px;
  align-items: center;
  padding: 32px 28px 36px;
  border-bottom: 1px solid var(--rule);
  transition: background 0.4s ease;
}
.paper:hover {
  background: linear-gradient(90deg, rgba(20, 184, 166, 0.08) 0%, transparent 60%);
}
.paper-aside {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px 14px;
  background: var(--paper);
  border: 1px solid var(--rule);
  border-radius: 6px;
  text-align: center;
  min-height: 78px;
  color: var(--ink);
  font-size: 13px;
  line-height: 1.4;
  overflow: hidden;
}
.paper-aside .katex {
  font-size: 0.9em;
  white-space: normal;
}
.paper-aside--image {
  padding: 8px;
  min-height: 0;
}
.paper-aside--image img {
  width: 100%;
  height: auto;
  max-height: 200px;
  object-fit: contain;
  display: block;
  border-radius: 3px;
}

/* Table-style aside — for papers with a comparison snapshot */
.paper-aside--table {
  flex-direction: column;
  align-items: stretch;
  justify-content: center;
  padding: 14px 16px;
  min-height: 0;
  text-align: left;
  overflow: hidden;
}
.paper-aside--table .aside-caption {
  margin: 0 0 8px;
}
.aside-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 11px;
  line-height: 1.5;
}
.aside-table th {
  text-align: left;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 9.5px;
  color: var(--muted);
  padding: 6px 10px 6px 0;
  border-bottom: 1px solid var(--rule);
  white-space: nowrap;
}
.aside-table th:last-child { padding-right: 0; }
.aside-table td {
  padding: 8px 10px 8px 0;
  border-bottom: 1px solid var(--rule);
  vertical-align: middle;
  color: var(--ink-soft);
  line-height: 1.35;
}
.aside-table th:first-child,
.aside-table td:first-child {
  width: 58%;
  word-break: break-word;
}
.aside-table td:last-child { padding-right: 0; }
.aside-table tbody tr:last-child td { border-bottom: 0; }
.aside-table tr.this-paper td {
  background: rgba(20, 184, 166, 0.1);
  color: var(--ink);
}
.aside-table tr.this-paper td:first-child {
  font-weight: 600;
  border-left: 2px solid var(--accent);
  padding-left: 8px;
}
.aside-table .katex {
  font-size: 0.82em;
  white-space: nowrap;
}

/* Larger right column + image — for papers with a figure snapshot */
.paper.paper--with-image {
  grid-template-columns: minmax(260px, 1fr) minmax(320px, 380px);
  align-items: center;
}
.paper.paper--with-image .paper-aside--image {
  padding: 10px;
}
.paper.paper--with-image .paper-aside--image img {
  max-height: 320px;
}
@media (max-width: 880px) {
  .paper.paper--with-image { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .paper { grid-template-columns: 1fr; gap: 16px; }
  .paper-aside { padding: 12px; min-height: 0; }
}

/* Wider equation panel on the right — for papers with a full multi-line formula */
.paper.paper--full-eq {
  grid-template-columns: minmax(260px, 1fr) minmax(380px, 1.4fr);
  align-items: start;
}
.paper.paper--full-eq .paper-aside {
  align-items: flex-start;
  flex-direction: column;
  padding: 18px 20px 20px;
  min-height: 0;
  text-align: left;
  overflow: hidden;
}
.paper.paper--full-eq .paper-aside .katex-display {
  margin: 0;
  text-align: left;
}
.paper.paper--full-eq .paper-aside .katex-display > .katex {
  text-align: left;
  font-size: 0.78em;
}
.aside-caption {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 10px;
  white-space: nowrap;
}
.caption-keep-case {
  text-transform: none;
}
@media (max-width: 880px) {
  .paper.paper--full-eq { grid-template-columns: 1fr; }
}
.paper-line {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 16px;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.paper-year {
  color: var(--muted);
  font-weight: 600;
}
.paper-venue {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--ink);
}
.paper-award {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 4px 11px;
  margin: -3px 0;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  letter-spacing: 0.1em;
  font-size: 11.5px;
  box-shadow: 0 4px 14px -6px rgba(20, 184, 166, 0.6);
}
.paper-title a {
  background-image: linear-gradient(transparent 60%, rgba(20, 184, 166, 0.18) 60%);
  background-size: 100% 100%;
  background-repeat: no-repeat;
}
.paper-title a:hover {
  background-image: linear-gradient(transparent 60%, rgba(20, 184, 166, 0.32) 60%);
}
.paper-title {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(22px, 2.4vw, 32px);
  line-height: 1.2;
  letter-spacing: -0.018em;
  margin: 0 0 14px;
  max-width: 28ch;
}
.paper-title a {
  position: relative;
  transition: color 0.25s;
}
.paper-title a:hover { color: var(--accent); }
.paper-authors {
  font-size: 14px;
  color: var(--ink-soft);
  margin: 0 0 16px;
  line-height: 1.55;
  max-width: 60ch;
}
.paper-authors strong { color: var(--ink); font-weight: 600; }
.paper-actions {
  display: flex;
  gap: 22px;
  font-size: 13px;
  font-weight: 500;
}
.paper-actions a {
  color: var(--ink);
  border-bottom: 1px solid transparent;
  padding-bottom: 2px;
  transition: color 0.25s, border-color 0.25s;
}
.paper-actions a:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* ---------- Footer ---------- */
.footer {
  border-top: 1px solid var(--rule);
  padding: 28px var(--gutter);
  max-width: var(--max);
  margin: 0 auto;
}
.footer-row {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: var(--ink-soft);
}
.footer p { margin: 0; }

/* ---------- Reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.9s ease, transform 0.9s ease;
}
.reveal.in {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  .reveal { opacity: 1; transform: none; }
  .hp { opacity: 1; transform: none; animation: none; }
}