/* Bivalent Bio — brochure site
   Clean, scientific, restrained. Navy primary, teal/cyan accent. */

:root {
  --navy:      #0B2447;
  --navy-700:  #143a6b;
  --navy-300:  #6e87a8;
  --teal:      #149a8e;
  --teal-600:  #0f7d73;
  --cyan:      #5fd0c4;
  --ink:       #16243a;
  --muted:     #56697f;
  --bg:        #ffffff;
  --bg-alt:    #f4f7f9;
  --bg-navy:   #0B2447;
  --line:      #e3eaf1;
  --shadow:    0 1px 2px rgba(16,36,58,.04), 0 8px 24px rgba(16,36,58,.06);
  --radius:    14px;
  --maxw:      1120px;
  --ease:      cubic-bezier(.16,.84,.44,1);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  font-weight: 650;
  line-height: 1.15;
  letter-spacing: -.018em;
  color: var(--navy);
  margin: 0 0 .5em;
}
h1 { font-size: clamp(2.1rem, 4.6vw, 3.4rem); font-weight: 700; }
h2 { font-size: clamp(1.55rem, 3vw, 2.2rem); }
h3 { font-size: 1.18rem; }
p  { margin: 0 0 1.1em; }

a { color: var(--teal-600); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

.eyebrow {
  text-transform: uppercase;
  letter-spacing: .14em;
  font-size: .74rem;
  font-weight: 650;
  color: var(--teal-600);
  margin: 0 0 .9em;
}
.lead { font-size: 1.18rem; color: var(--muted); max-width: 62ch; }
.muted { color: var(--muted); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: .5em;
  font-weight: 600;
  font-size: .96rem;
  padding: .72em 1.4em;
  border-radius: 999px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .15s var(--ease), background .15s, border-color .15s, color .15s;
  white-space: nowrap;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary { background: var(--teal); color: #fff; }
.btn-primary:hover { background: var(--teal-600); color: #fff; }
.btn-outline { background: transparent; color: var(--navy); border-color: var(--line); }
.btn-outline:hover { border-color: var(--navy-300); }
.btn-ghost-light { background: rgba(255,255,255,.08); color: #fff; border-color: rgba(255,255,255,.28); }
.btn-ghost-light:hover { background: rgba(255,255,255,.16); color: #fff; }
.btn-light { background: #fff; color: var(--navy); }
.btn-light:hover { background: #eef3f7; color: var(--navy); }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.85);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 70px; }
.brand { display: inline-flex; align-items: center; gap: .6em; color: var(--navy); font-weight: 700; font-size: 1.12rem; letter-spacing: -.02em; }
.brand:hover { text-decoration: none; }
.brand span strong { color: var(--teal-600); font-weight: 700; }
.brand .logo { width: 30px; height: 30px; flex: none; }

.nav { display: flex; align-items: center; gap: 8px; }
.nav-links { list-style: none; display: flex; align-items: center; gap: 4px; margin: 0; padding: 0; }
.nav-links a {
  color: var(--ink);
  font-weight: 500;
  font-size: .95rem;
  padding: .5em .8em;
  border-radius: 8px;
  transition: background .15s, color .15s;
}
.nav-links a:hover { background: var(--bg-alt); text-decoration: none; }
.nav-links a[aria-current="page"] { color: var(--teal-600); }
.nav-links .nav-cta a { color: #fff; padding: .58em 1.15em; margin-left: 8px; }
.nav-links .nav-cta a:hover { background: var(--teal-600); }

.nav-toggle {
  display: none;
  background: none; border: 1px solid var(--line);
  border-radius: 9px; padding: 9px; cursor: pointer;
}
.nav-toggle svg { display: block; }

/* ---------- Section helpers ---------- */
section { padding: 84px 0; }
section.tight { padding: 60px 0; }
.bg-alt { background: var(--bg-alt); }
.bg-navy { background: var(--bg-navy); color: #fff; }
.bg-navy h1, .bg-navy h2, .bg-navy h3 { color: #fff; }
.bg-navy .lead, .bg-navy p { color: rgba(255,255,255,.82); }
.bg-navy .eyebrow { color: var(--cyan); }

.section-head { max-width: 64ch; margin-bottom: 48px; }
.center { text-align: center; margin-left: auto; margin-right: auto; }

/* ---------- Hero ---------- */
.hero { position: relative; overflow: hidden; background: linear-gradient(180deg, #fff 0%, var(--bg-alt) 100%); padding: 96px 0 88px; }
.hero-grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: 56px; align-items: center; }
.hero h1 { margin-bottom: .35em; }
.hero .lead { font-size: 1.28rem; margin-bottom: 1.6em; }
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-visual { display: flex; justify-content: center; }
.hero-visual svg { width: 100%; max-width: 420px; height: auto; }

/* ---------- Cards / grids ---------- */
.grid { display: grid; gap: 24px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.card {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 28px;
  box-shadow: var(--shadow);
  transition: transform .2s var(--ease), box-shadow .2s;
}
.card:hover { transform: translateY(-3px); box-shadow: 0 12px 36px rgba(16,36,58,.10); }
.card .icon { width: 44px; height: 44px; margin-bottom: 18px; color: var(--teal); }
.card h3 { margin-bottom: .35em; }
.card p:last-child { margin-bottom: 0; }

.pillars { counter-reset: pillar; }
.pillar { display: flex; gap: 20px; padding: 26px 0; border-top: 1px solid var(--line); }
.pillar:last-child { border-bottom: 1px solid var(--line); }
.pillar .num { counter-increment: pillar; font-variant-numeric: tabular-nums; font-weight: 700; color: var(--teal); font-size: 1.4rem; min-width: 44px; }
.pillar .num::before { content: "0" counter(pillar); }
.pillar h3 { margin-bottom: .2em; }
.pillar p:last-child { margin-bottom: 0; }

/* ---------- Pipeline ---------- */
.pipeline { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); background: #fff; }
.pl-row {
  display: grid;
  grid-template-columns: 1.1fr .9fr 1.5fr 3.2fr;
  gap: 18px;
  align-items: center;
  padding: 20px 24px;
  border-top: 1px solid var(--line);
}
.pl-row:first-child { border-top: 0; }
.pl-head { background: var(--bg-alt); font-size: .76rem; text-transform: uppercase; letter-spacing: .09em; font-weight: 650; color: var(--muted); }
.pl-prog { font-weight: 650; color: var(--navy); }
.pl-prog small { display: block; font-weight: 500; color: var(--muted); font-size: .82rem; text-transform: none; letter-spacing: 0; margin-top: 2px; }
.pl-cell-label { display: none; }

/* phase track */
.phases-head { display: grid; grid-template-columns: repeat(4,1fr); gap: 6px; }
.phases-head span { text-align: center; font-size: .68rem; }
.track { position: relative; height: 40px; }
.track-grid { position: absolute; inset: 0; display: grid; grid-template-columns: repeat(4,1fr); gap: 6px; }
.track-grid i { background: var(--bg-alt); border-radius: 7px; border: 1px solid var(--line); }
.track-fill {
  position: absolute; top: 0; bottom: 0; left: 0;
  border-radius: 7px;
  background: linear-gradient(90deg, var(--navy-700), var(--teal));
  display: flex; align-items: center; justify-content: flex-end;
  padding-right: 12px;
  color: #fff; font-size: .74rem; font-weight: 600;
  box-shadow: 0 1px 6px rgba(20,154,142,.35);
}
.track-fill[data-stage="1"] { width: calc(25% - 3px); }
.track-fill[data-stage="2"] { width: calc(50% - 3px); }
.track-fill[data-stage="3"] { width: calc(75% - 3px); }
.track-fill[data-stage="4"] { width: 100%; }

/* lead programme highlight */
.lead-prog { display: grid; grid-template-columns: .9fr 1.1fr; gap: 40px; align-items: center; }
.lead-prog .badge { display: inline-block; background: rgba(20,154,142,.12); color: var(--teal-600); font-weight: 650; font-size: .76rem; letter-spacing: .06em; text-transform: uppercase; padding: .35em .8em; border-radius: 999px; margin-bottom: 16px; }

/* ---------- Team ---------- */
.people { display: grid; grid-template-columns: repeat(4,1fr); gap: 24px; }
.person { text-align: left; }
.person .portrait {
  width: 100%; aspect-ratio: 1/1; border-radius: var(--radius);
  background: var(--bg-alt); border: 1px solid var(--line);
  display: flex; align-items: flex-end; justify-content: center; overflow: hidden; margin-bottom: 16px;
}
.person .portrait svg { width: 72%; height: auto; color: var(--navy-300); }
.person h3 { font-size: 1.05rem; margin-bottom: .15em; }
.person .role { color: var(--teal-600); font-weight: 600; font-size: .9rem; margin-bottom: .4em; }
.person p { font-size: .92rem; color: var(--muted); margin: 0; }

.advisors { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2,1fr); gap: 18px; }
.advisors li { padding: 18px 22px; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
.advisors strong { color: var(--navy); display: block; }
.advisors span { color: var(--muted); font-size: .92rem; }

/* ---------- News ---------- */
.news-list { list-style: none; padding: 0; margin: 0; }
.news-item { display: grid; grid-template-columns: 150px 1fr; gap: 28px; padding: 28px 0; border-top: 1px solid var(--line); }
.news-item:first-child { border-top: 0; }
.news-item time { color: var(--muted); font-weight: 600; font-size: .9rem; }
.news-item h3 { margin-bottom: .3em; }
.news-item p { margin-bottom: .5em; color: var(--muted); }
.read-more { font-weight: 600; font-size: .92rem; }

.news-cards { display: grid; grid-template-columns: repeat(3,1fr); gap: 24px; }
.news-card time { color: var(--teal-600); font-weight: 600; font-size: .82rem; }
.news-card h3 { font-size: 1.05rem; margin: .4em 0; }
.news-card p { font-size: .92rem; color: var(--muted); }

/* ---------- Careers ---------- */
.roles { list-style: none; padding: 0; margin: 0; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.roles li { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 22px 26px; border-top: 1px solid var(--line); background: #fff; }
.roles li:first-child { border-top: 0; }
.roles .role-title { font-weight: 650; color: var(--navy); }
.roles .role-loc { color: var(--muted); font-size: .92rem; }

/* ---------- Contact ---------- */
.contact-cards { display: grid; grid-template-columns: repeat(3,1fr); gap: 24px; margin-bottom: 56px; }
.contact-card h3 { font-size: 1rem; }
.contact-card a { font-weight: 600; }

.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.field { display: flex; flex-direction: column; gap: 7px; }
.field.full { grid-column: 1 / -1; }
.field label { font-weight: 600; font-size: .9rem; color: var(--navy); }
.field input, .field select, .field textarea {
  font: inherit; font-size: .98rem;
  padding: .72em .9em;
  border: 1px solid var(--line); border-radius: 10px;
  background: #fff; color: var(--ink);
  transition: border-color .15s, box-shadow .15s;
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none; border-color: var(--teal);
  box-shadow: 0 0 0 3px rgba(20,154,142,.15);
}
.field textarea { resize: vertical; min-height: 130px; }
.form-note { font-size: .85rem; color: var(--muted); margin-top: 14px; }
.form-success {
  display: none;
  background: rgba(20,154,142,.08);
  border: 1px solid rgba(20,154,142,.3);
  color: var(--teal-600);
  padding: 16px 18px; border-radius: 10px; font-weight: 500;
}
.form-success.show { display: block; }

/* ---------- CTA strip ---------- */
.cta-strip { background: var(--bg-navy); border-radius: var(--radius); padding: 56px; display: flex; align-items: center; justify-content: space-between; gap: 32px; flex-wrap: wrap; position: relative; overflow: hidden; }
.cta-strip h2 { color: #fff; margin: 0 0 .2em; }
.cta-strip p { color: rgba(255,255,255,.8); margin: 0; max-width: 52ch; }
.cta-strip .cta-strip-text { position: relative; z-index: 1; }
.cta-strip .btn { position: relative; z-index: 1; }
.cta-deco { position: absolute; right: -40px; top: 50%; transform: translateY(-50%); opacity: .14; width: 320px; height: auto; color: var(--cyan); }

/* ---------- Footer ---------- */
.site-footer { background: var(--bg-navy); color: rgba(255,255,255,.7); padding: 64px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr; gap: 40px; padding-bottom: 40px; border-bottom: 1px solid rgba(255,255,255,.12); }
.footer-grid .brand { color: #fff; margin-bottom: 14px; }
.footer-grid .brand span strong { color: var(--cyan); }
.site-footer h4 { color: #fff; font-size: .85rem; text-transform: uppercase; letter-spacing: .1em; margin-bottom: 16px; }
.site-footer p { color: rgba(255,255,255,.6); font-size: .92rem; }
.footer-links { list-style: none; padding: 0; margin: 0; }
.footer-links li { margin-bottom: 10px; }
.footer-links a { color: rgba(255,255,255,.72); font-size: .92rem; }
.footer-links a:hover { color: #fff; }
.footer-bottom { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; padding-top: 24px; font-size: .84rem; color: rgba(255,255,255,.5); }
.footer-bottom .legal { display: flex; gap: 20px; }
.footer-bottom a { color: rgba(255,255,255,.55); }

/* ---------- Page hero (interior) ---------- */
.page-hero { background: linear-gradient(180deg,#fff,var(--bg-alt)); padding: 70px 0 56px; border-bottom: 1px solid var(--line); }
.page-hero .lead { margin-bottom: 0; }

/* ---------- Reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s var(--ease), transform .6s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------- Responsive ---------- */
@media (max-width: 940px) {
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .hero-visual { order: -1; max-width: 320px; margin: 0 auto; }
  .grid-3, .news-cards, .contact-cards { grid-template-columns: 1fr 1fr; }
  .people { grid-template-columns: 1fr 1fr; }
  .lead-prog { grid-template-columns: 1fr; gap: 28px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 760px) {
  .nav-toggle { display: inline-flex; }
  .nav-links {
    position: absolute; top: 70px; left: 0; right: 0;
    flex-direction: column; align-items: stretch;
    background: #fff; border-bottom: 1px solid var(--line);
    padding: 12px 16px 18px; gap: 4px;
    box-shadow: var(--shadow);
    display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: .8em 1em; }
  .nav-links .nav-cta a { margin-left: 0; text-align: center; justify-content: center; }

  section { padding: 56px 0; }
  .grid-3, .grid-2, .news-cards, .contact-cards, .people, .advisors, .form-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .news-item { grid-template-columns: 1fr; gap: 6px; }
  .cta-strip { padding: 36px 28px; }
  .roles li { flex-direction: column; align-items: flex-start; gap: 10px; }

  /* pipeline -> stacked cards */
  .pipeline { border: 0; box-shadow: none; background: transparent; }
  .pl-head { display: none; }
  .pl-row {
    grid-template-columns: 1fr;
    gap: 12px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    margin-bottom: 16px;
    background: #fff;
    box-shadow: var(--shadow);
  }
  .pl-cell-label { display: block; font-size: .7rem; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); font-weight: 650; margin-bottom: 2px; }
  .phases-head { display: none; }
}