/* ===================================================================
   TC-WM Project Page — Editorial Academic Theme
   Aesthetic: warm paper, Castoro serif display, restrained accent blue.
   =================================================================== */

:root {
  --bg:           #faf8f3;
  --bg-card:      #ffffff;
  --bg-soft:      #f1ede5;
  --ink:          #1d2733;
  --ink-2:        #4a5568;
  --ink-muted:    #6b7280;
  --accent:       #28679E;
  --accent-deep:  #1a4670;
  --accent-soft:  rgba(40, 103, 158, 0.10);
  --rule:         #e8e2d4;
  --rule-strong:  #d2cab5;
  --pill:         #1d2733;
  --pill-hover:   #2a3949;
  --shadow-card:        0 1px 2px rgba(29, 39, 51, 0.04), 0 4px 16px rgba(29, 39, 51, 0.05);
  --shadow-card-hover:  0 6px 24px rgba(40, 103, 158, 0.10), 0 1px 2px rgba(29, 39, 51, 0.06);
  --font-display: 'Castoro', 'Castoro Slab', Georgia, 'Times New Roman', serif;
  --font-body:    'Noto Sans', 'Inter', system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  --font-tag:     'Google Sans', 'Inter', system-ui, sans-serif;
  --font-mono:    'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 4rem; }

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background-color: var(--bg);
  background-image:
    radial-gradient(rgba(0,0,0,0.014) 1px, transparent 1px),
    radial-gradient(rgba(0,0,0,0.012) 1px, transparent 1px);
  background-size: 5px 5px, 5px 5px;
  background-position: 0 0, 2.5px 2.5px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a, a:visited { color: var(--accent); text-decoration: none; transition: color 0.15s ease; }
a:hover { color: var(--accent-deep); }

::selection { background: var(--accent-soft); color: var(--accent-deep); }

/* ---------- Navbar ---------------------------------------------------- */
.navbar {
  background: rgba(250, 248, 243, 0.86);
  backdrop-filter: saturate(150%) blur(14px);
  -webkit-backdrop-filter: saturate(150%) blur(14px);
  border-bottom: 1px solid var(--rule);
  position: sticky; top: 0; z-index: 100;
  min-height: 3.2rem;
  box-shadow: 0 1px 0 rgba(0,0,0,0.02);
}
.navbar-brand .navbar-item { padding: 0 1rem; }
.navbar-brand .fa-home { color: var(--accent); transition: color 0.15s; }
.navbar-brand .navbar-item:hover { background: transparent; }
.navbar-brand .navbar-item:hover .fa-home { color: var(--accent-deep); }

.nav-center { flex-grow: 1; justify-content: center; }

.navbar-menu .navbar-item {
  font-family: var(--font-tag);
  font-size: 0.85rem;
  letter-spacing: 0.02em;
  color: var(--ink-2);
  position: relative;
  padding: 0.5rem 0.9rem;
}
.navbar-menu .navbar-item:hover {
  background: transparent;
  color: var(--accent);
}
.navbar-menu .navbar-item::after {
  content: "";
  position: absolute;
  left: 50%; right: 50%; bottom: 0.45rem;
  height: 1.5px;
  background: var(--accent);
  border-radius: 2px;
  transition: left 0.18s ease, right 0.18s ease;
}
.navbar-menu .navbar-item:hover::after { left: 0.9rem; right: 0.9rem; }

/* ---------- Hero ------------------------------------------------------ */
.hero { background: transparent; }
.hero-body {
  padding: 5.5rem 1.5rem 3.5rem;
}

.kicker {
  display: inline-flex; align-items: center; gap: 0.85rem;
  font-family: var(--font-tag);
  font-size: 0.7rem;
  letter-spacing: 0.34em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.6rem;
  animation: fadeUp 0.6s ease-out both;
}
.kicker::before, .kicker::after {
  content: "";
  width: 28px; height: 1px;
  background: var(--accent);
  opacity: 0.55;
}

.publication-title {
  font-family: var(--font-display) !important;
  font-weight: 400 !important;
  font-size: clamp(2.1rem, 4.4vw, 3.2rem) !important;
  line-height: 1.14 !important;
  letter-spacing: -0.006em;
  color: var(--ink) !important;
  margin-bottom: 1.5rem !important;
  max-width: 880px;
  animation: fadeUp 0.75s ease-out both;
}
.publication-title .accent { color: var(--accent); font-style: italic; }

.tagline {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1.18rem;
  color: var(--ink-2);
  max-width: 720px;
  margin: 0 auto 2.2rem;
  line-height: 1.55;
  animation: fadeUp 0.85s ease-out 0.1s both;
}

.publication-links {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 0.6rem;
  margin: 0 auto;
  animation: fadeUp 0.95s ease-out 0.2s both;
}

.publication-links a.btn {
  display: inline-flex; align-items: center; gap: 0.55rem;
  padding: 0.6rem 1.45rem;
  font-family: var(--font-tag);
  font-size: 0.92rem; font-weight: 500;
  letter-spacing: 0.015em;
  border-radius: 999px;
  background: var(--pill); color: #fff !important;
  border: 1px solid transparent;
  transition: background-color 0.18s ease, transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
  cursor: pointer;
}
.publication-links a.btn:hover {
  background: var(--pill-hover);
  color: #fff !important;
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(29, 39, 51, 0.18);
}
.publication-links a.btn .icon { font-size: 0.92em; }
.publication-links a.btn.is-accent { background: var(--accent); }
.publication-links a.btn.is-accent:hover {
  background: var(--accent-deep);
  box-shadow: 0 6px 18px rgba(40, 103, 158, 0.30);
}
.publication-links a.btn.is-disabled,
.publication-links a.btn.is-disabled-link {
  background: transparent !important;
  color: var(--ink-muted) !important;
  border-color: var(--rule-strong);
  cursor: not-allowed;
  pointer-events: none;
  box-shadow: none;
}
.publication-links a.btn.is-disabled:hover { transform: none; }

/* ---------- Section layout & editorial headings ----------------------- */
.section {
  padding: 4.5rem 1.5rem;
  position: relative;
}
.container.is-max-desktop { max-width: 960px; }

/* soft hairline between sections */
.section + .section::before {
  content: "";
  position: absolute;
  top: 0; left: 50%;
  transform: translateX(-50%);
  width: 92%; max-width: 720px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--rule-strong), transparent);
}

/* editorial section heading: small accent tick + serif title */
.section > .container > h2.title.is-3,
.section > .container > .abstract-block > h2.title.is-3 {
  font-family: var(--font-display) !important;
  font-weight: 400 !important;
  font-size: 2rem !important;
  font-style: normal;
  color: var(--ink) !important;
  text-align: center;
  position: relative;
  margin: 0 auto 2rem !important;
  padding-top: 0.4rem;
  letter-spacing: -0.003em;
}
.section > .container > h2.title.is-3::before,
.section > .container > .abstract-block > h2.title.is-3::before {
  content: "";
  display: block;
  width: 34px; height: 2px;
  background: var(--accent);
  margin: 0 auto 1rem;
  border-radius: 2px;
}

/* ---------- Prose / content ------------------------------------------ */
.content p, .abstract-text {
  font-size: 1rem;
  line-height: 1.74;
  color: var(--ink-2);
}
.content strong, .abstract-text strong { color: var(--ink); font-weight: 600; }
.content em, .abstract-text em {
  font-family: var(--font-display);
  font-style: italic;
  color: var(--ink);
}
.content ul {
  margin-top: 0.6rem; margin-bottom: 1.2rem;
  padding-left: 1.4rem;
}
.content ul li {
  margin-bottom: 0.5rem;
  line-height: 1.65;
}
.content ul li::marker { color: var(--accent); }

/* inline code chip */
.content code,
p code,
.abstract-text code,
.figure-caption code {
  font-family: var(--font-mono);
  font-size: 0.86em;
  padding: 0.08em 0.42em;
  border-radius: 4px;
  background: var(--bg-soft);
  color: var(--accent-deep);
  border: 1px solid var(--rule);
  white-space: nowrap;
}

/* ---------- Abstract ------------------------------------------------- */
.abstract-block { max-width: 760px; margin: 0 auto; }
.abstract-text {
  font-size: 1.04rem;
  line-height: 1.78;
  color: var(--ink-2);
  text-align: justify;
  hyphens: auto;
  text-justify: inter-word;
}

/* ---------- Figures -------------------------------------------------- */
.figure-img {
  width: 100%;
  height: auto;
  display: block;
  background: var(--bg-card);
  border: 1px solid var(--rule);
  border-radius: 10px;
  box-shadow: var(--shadow-card);
  margin: 1.6rem 0 0.7rem;
  padding: 0.4rem;
}
.figure-img.figure-main {
  max-height: 700px;
  object-fit: contain;
  padding: 1.2rem;
}

.figure-caption {
  font-family: var(--font-body);
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--ink-muted);
  text-align: left;
  max-width: 820px;
  margin: 0.7rem auto 1.8rem;
  padding-left: 1rem;
  border-left: 2px solid var(--accent);
}
.figure-caption strong { color: var(--ink); font-weight: 600; }

/* ---------- Environments grid (3x3) ---------------------------------- */
.env-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(140px, 180px));
  justify-content: center;
  gap: 0.9rem;
  margin: 1.5rem auto 0;
  max-width: 620px;
}
.env-card {
  background: var(--bg-card);
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 0.5rem 0.5rem 0.45rem;
  text-align: center;
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}
.env-card:hover {
  transform: translateY(-2px);
  border-color: rgba(40, 103, 158, 0.35);
  box-shadow: var(--shadow-card-hover);
}
.env-card img {
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: 6px;
  display: block;
  background: var(--bg-soft);
  border: 1px solid var(--rule);
}
.env-tag {
  display: inline-block;
  margin-top: 0.45rem;
  font-family: var(--font-tag);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.025em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.14rem 0.65rem;
  border-radius: 999px;
  border: none;
}

/* hide the old .dataset-row stacking layout — replaced by .env-grid */
.dataset-row { display: none; }

/* ---------- World Model Rollouts (3x2 grid of 3-cell rows) ----------- */
.rollout-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.1rem;
  margin-top: 1.4rem;
}
.rollout-card {
  background: var(--bg-card);
  border: 1px solid var(--rule);
  border-radius: 10px;
  padding: 0.75rem 0.75rem 0.7rem;
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}
.rollout-card:hover {
  transform: translateY(-2px);
  border-color: rgba(40, 103, 158, 0.35);
  box-shadow: var(--shadow-card-hover);
}
.rollout-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.35rem;
}
.rollout-cell {
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: 0;
}
.rollout-cell img {
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: 5px;
  display: block;
  background: var(--bg-soft);
  border: 1px solid var(--rule);
}
.rollout-label {
  display: block;
  margin-top: 0.4rem;
  font-family: var(--font-tag);
  font-size: 0.62rem;
  color: var(--ink-muted);
  text-align: center;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  font-weight: 500;
}
.rollout-task {
  margin: 0.75rem 0 0.05rem;
  text-align: center;
}
.rollout-task code {
  display: inline-block;
  font-family: var(--font-tag);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.2rem 0.78rem;
  border-radius: 999px;
  border: none;
  white-space: nowrap;
}

/* ---------- Footer --------------------------------------------------- */
footer.footer {
  background: transparent;
  border-top: 1px solid var(--rule);
  padding: 2rem 1.5rem 2.5rem;
  margin-top: 2rem;
}
footer.footer .content p {
  font-family: var(--font-tag);
  font-size: 0.78rem;
  color: var(--ink-muted);
  letter-spacing: 0.04em;
  text-align: center;
}

/* ---------- Motion --------------------------------------------------- */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ---------- Responsive ----------------------------------------------- */
@media (max-width: 1024px) {
  .env-grid { grid-template-columns: repeat(3, minmax(110px, 1fr)); max-width: 540px; }
  .rollout-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .env-grid { grid-template-columns: repeat(2, 1fr); max-width: 360px; }
}

@media (max-width: 720px) {
  .hero-body { padding: 4rem 1rem 2.5rem; }
  .section { padding: 3.5rem 1rem; }
  .section > .container > h2.title.is-3,
  .section > .container > .abstract-block > h2.title.is-3 {
    font-size: 1.65rem !important;
  }
  .publication-title { font-size: 1.85rem !important; }
  .tagline { font-size: 1rem; }
  .abstract-text { text-align: left; }
  .figure-caption { font-size: 0.84rem; }
}

@media (max-width: 480px) {
  .env-grid, .rollout-grid { grid-template-columns: 1fr; }
  .rollout-cell img { aspect-ratio: auto; }
}

/* ---------- Legacy / unused fallbacks (kept for safety) -------------- */
.dataset-cell, .demo-card, .dataset-gif, .demo-caption, .demo-label,
.bibtex-section, .bibtex-block,
.conference-tag, .figure-caption-old,
.publication-authors, .author-block, .link-block, .is-disabled-link {
  /* no-op fallback; not used in current HTML */
}

.rollout-row.is-4 {
  grid-template-columns: repeat(4, 1fr);
}
.rollout-row.is-4 .rollout-cell .rollout-label-strong {
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.perturb-divider {
  display: grid;
  grid-template-columns: 2fr 2fr;
  font-family: var(--font-tag);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-muted);
  text-align: center;
  margin-top: 0.5rem;
}
.perturb-divider span:nth-child(1) { color: var(--ink-2); }
.perturb-divider span:nth-child(2) { color: var(--accent); }