/* ==========================================================================
   HELIX — the research-first laboratory desktop.
   White ground, ink-navy type, a single blue→teal gradient used sparingly,
   programme cards and a publication list. The site as an open lab notebook.
   ========================================================================== */

.theme-helix {
  --paper:        #ffffff;
  --paper-2:      #f4f7fb;
  --paper-3:      #e8eef6;
  --dark:         #10141d;
  --dark-2:       #171d29;
  --dark-3:       #1f2735;
  --ink:          #1f2430;
  --ink-2:        #444b5a;
  --muted:        #7a8494;
  --muted-dark:   #9aa3b2;
  --clay:         #0b57d0;
  --clay-deep:    #0842a0;
  --clay-soft:    #d3e3fd;
  --sky:          #00a3bf;
  --sage:         #00a3bf;
  --line:         rgba(31, 36, 48, 0.12);
  --line-strong:  rgba(31, 36, 48, 0.24);
  --line-dark:    rgba(255, 255, 255, 0.14);
  --r-xs: 6px;
  --r-sm: 8px;
  --r:    12px;
  --r-lg: 14px;
  --r-xl: 18px;
  --r-pill: 999px;
  --serif: "Space Grotesk", "Inter", sans-serif;
  --sans:  "Inter", sans-serif;
}

.theme-helix ::selection { background: var(--clay-soft); }
.theme-helix :focus-visible { outline: 2px solid var(--clay); outline-offset: 3px; }

/* ---- chrome ---------------------------------------------------------- */

.theme-helix .site-header { background: rgba(255, 255, 255, 0.88); }
.theme-helix .promo { background: linear-gradient(100deg, #0842a0, #00796b); }
.theme-helix .brand-mark { color: var(--clay); }
.theme-helix .nav-link:hover, .theme-helix .nav-trigger:hover { background: var(--paper-2); color: var(--clay-deep); }
.theme-helix .mega__link:hover { background: var(--paper-2); color: var(--clay-deep); }
.theme-helix .drawer { background: #fff; }

/* ---- links & buttons -------------------------------------------------- */

.theme-helix .btn--primary { background: var(--clay); }
.theme-helix .btn--primary:hover { background: var(--clay-deep); }
.theme-helix .btn--clay { background: linear-gradient(110deg, #0b57d0, #00a3bf); }
.theme-helix .btn--clay:hover { background: linear-gradient(110deg, #0842a0, #007f9e); }
.theme-helix .arrow-link { color: var(--clay); }
.theme-helix .hub-link:hover, .theme-helix .lang-toggle:hover {
  background: var(--clay); border-color: var(--clay); color: #fff;
}

/* ---- type ------------------------------------------------------------- */

.theme-helix .hero h1,
.theme-helix .page-hero h1,
.theme-helix .section-head h2,
.theme-helix .callout__copy h2,
.theme-helix .card h3,
.theme-helix .tile__title,
.theme-helix .release__title,
.theme-helix .timeline__item h3 {
  font-family: var(--serif);
  font-weight: 600;
  letter-spacing: -0.025em;
}
.theme-helix .hero h1 a { color: var(--clay); text-decoration-color: rgba(11, 87, 208, 0.4); }
.theme-helix .eyebrow { color: var(--clay); }
.theme-helix .mission em {
  font-style: normal;
  background: linear-gradient(110deg, #0b57d0, #00a3bf);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.theme-helix .prose blockquote { border-left-color: var(--clay); }
.theme-helix .prose ul li::before { background: var(--clay); }
.theme-helix .chip--clay { color: var(--clay); border-color: rgba(11, 87, 208, 0.35); }

/* ---- surfaces --------------------------------------------------------- */

.theme-helix .hero__glow {
  background:
    radial-gradient(closest-side, rgba(11, 87, 208, 0.14), transparent 72%),
    radial-gradient(closest-side at 62% 58%, rgba(0, 163, 191, 0.12), transparent 70%);
}
.theme-helix .card:hover { border-color: rgba(11, 87, 208, 0.4); }
.theme-helix .tile:hover { background: var(--paper-2); }
.theme-helix .tile__arrow { color: var(--clay); }
.theme-helix .callout__viz {
  background:
    radial-gradient(120% 90% at 80% 15%, rgba(11, 87, 208, 0.5), transparent 60%),
    radial-gradient(90% 80% at 12% 90%, rgba(0, 163, 191, 0.35), transparent 62%),
    var(--dark-3);
}
.theme-helix .table thead th { background: var(--paper-2); color: var(--clay-deep); }
.theme-helix .tier { background: linear-gradient(110deg, #0b57d0, #00a3bf); }
.theme-helix .stat dd { color: var(--clay-deep); }
.theme-helix .section--paper2 { background: var(--paper-2); }
.theme-helix .timeline__year { color: var(--clay); }
.theme-helix .job:hover { color: var(--clay-deep); }
.theme-helix .person__photo { background: linear-gradient(160deg, var(--paper-3), var(--paper-2)); }
.theme-helix .filter.is-active { background: var(--clay); border-color: var(--clay); }
.theme-helix .footer__brand .brand-mark { color: #8ab4f8; }

/* ==========================================================================
   HELIX home — research-first architecture.
   ========================================================================== */

.hl-hero {
  max-width: 1160px;
  margin-inline: auto;
  padding: clamp(48px, 8vw, 104px) var(--gutter) clamp(28px, 4vw, 48px);
}
.hl-eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--clay);
  margin: 0;
}
.hl-hero h1 {
  margin: 22px 0 0;
  max-width: 22ch;
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(38px, 6.4vw, 76px);
  line-height: 1.04;
  letter-spacing: -0.03em;
}
.hl-hero h1 em {
  font-style: normal;
  background: linear-gradient(105deg, #0b57d0 15%, #00a3bf 85%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hl-lede { margin: 22px 0 0; max-width: 60ch; font-size: clamp(16px, 1.8vw, 19px); line-height: 1.65; color: var(--ink-2); }
.hl-actions { margin-top: 30px; display: flex; flex-wrap: wrap; gap: 12px; }

/* programme grid */
.hl-section { max-width: 1160px; margin-inline: auto; padding: clamp(40px, 6vw, 72px) var(--gutter); }
.hl-label {
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 22px;
}
.hl-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.hl-prog {
  display: grid;
  grid-template-columns: 52px 1fr;
  gap: 16px;
  padding: 22px 24px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  transition: border-color 0.25s var(--ease), background 0.25s var(--ease);
}
.hl-prog:hover { border-color: rgba(11, 87, 208, 0.45); background: var(--paper-2); }
.hl-prog-no {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--clay);
  padding-top: 3px;
}
.hl-prog h3 { font-family: var(--serif); font-weight: 600; font-size: 19px; letter-spacing: -0.015em; }
.hl-prog p { margin: 7px 0 0; font-size: 14px; line-height: 1.6; color: var(--muted); }
@media (max-width: 800px) { .hl-grid { grid-template-columns: 1fr; } }

/* publication list */
.hl-pubs { border-top: 1px solid var(--line-strong); }
.hl-pub {
  display: grid;
  grid-template-columns: 120px 1fr auto;
  gap: 22px;
  align-items: baseline;
  padding: 20px 4px;
  border-bottom: 1px solid var(--line);
  transition: background 0.2s var(--ease);
}
.hl-pub:hover { background: var(--paper-2); }
.hl-pub-date { font-family: var(--mono); font-size: 12.5px; color: var(--muted); }
.hl-pub h3 { font-family: var(--serif); font-weight: 600; font-size: 18px; letter-spacing: -0.01em; }
.hl-pub p { margin: 6px 0 0; font-size: 14px; line-height: 1.6; color: var(--ink-2); max-width: 68ch; }
.hl-pub-tag {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--clay);
  white-space: nowrap;
}
@media (max-width: 700px) { .hl-pub { grid-template-columns: 1fr; gap: 6px; } }

/* stat band */
.hl-band {
  margin: clamp(24px, 4vw, 48px) var(--gutter) 0;
  border-radius: var(--r-xl);
  background: linear-gradient(115deg, #10141d 0%, #0d2b52 55%, #06404a 100%);
  color: #fff;
  padding: clamp(36px, 6vw, 64px) clamp(24px, 5vw, 64px);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 28px;
}
.hl-band-figure { font-family: var(--serif); font-weight: 600; font-size: clamp(30px, 4vw, 46px); letter-spacing: -0.02em; }
.hl-band-figure span { color: #8ab4f8; }
.hl-band-label { margin-top: 8px; font-size: 13.5px; color: rgba(255, 255, 255, 0.66); }
@media (max-width: 800px) { .hl-band { grid-template-columns: repeat(2, 1fr); } }

/* responsibility strip */
.hl-resp {
  max-width: 1160px;
  margin-inline: auto;
  padding: clamp(36px, 5vw, 56px) var(--gutter);
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: clamp(24px, 4vw, 56px);
  align-items: center;
}
.hl-resp h2 { margin: 0; font-family: var(--serif); font-weight: 600; font-size: clamp(24px, 3.2vw, 36px); letter-spacing: -0.02em; }
.hl-resp p { margin: 14px 0 0; color: var(--ink-2); font-size: 15.5px; line-height: 1.7; }
@media (max-width: 800px) { .hl-resp { grid-template-columns: 1fr; } }

/* CJK tuning */
html[lang^="zh"] .theme-helix .hero h1,
html[lang^="zh"] .hl-hero h1 { line-height: 1.16; }

/* colophon footer (shared markup, self-styled here) */
.theme-helix .at-colophon {
  max-width: 1160px;
  margin-inline: auto;
  padding: 18px var(--gutter) 40px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}
.theme-helix .at-colophon a { color: var(--clay); font-weight: 500; }