/* =========================================================
   Dr Rini Chatterjee — Biological Coherence in Architecture
   Design system: architectural, elemental, spacious, rigorous.
   ========================================================= */

:root {
  --cream:      #FBF3E2;
  --stone:      #F1E7CC;
  --charcoal:   #2A2016;
  --charcoal-70: rgba(42, 32, 22, 0.72);
  --charcoal-45: rgba(42, 32, 22, 0.48);
  --clay:       #A6543E;
  --clay-dark:  #863F2E;
  --gold:       #BD9645;
  --gold-dark:  #96742F;
  --sage:       #8FA07A;
  --sage-dark:  #62704F;
  --olive:      #55552C;
  --olive-dark: #3F3F20;
  --moss:       var(--olive);
  --moss-dark:  var(--olive-dark);
  --navy:       #1B2142;
  --navy-dark:  #10142B;
  --line:       rgba(42, 32, 22, 0.14);
  --line-strong: rgba(42, 32, 22, 0.26);

  --font-display: "Fraunces", "Iowan Old Style", "Palatino Linotype", serif;
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;

  --container: 1180px;
  --gutter: clamp(24px, 5vw, 72px);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--cream);
  color: var(--charcoal);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }

a { color: inherit; }

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.12;
  letter-spacing: -0.01em;
  margin: 0 0 0.5em;
}

h1 { font-size: clamp(2.6rem, 5vw, 4.4rem); font-weight: 480; }
h2 { font-size: clamp(1.9rem, 3.2vw, 2.75rem); }
h3 { font-size: clamp(1.3rem, 2vw, 1.6rem); }

p { margin: 0 0 1.2em; }

.eyebrow {
  display: inline-block;
  font-family: var(--font-body);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--clay-dark);
  margin-bottom: 1.1em;
}

.lede {
  font-size: clamp(1.05rem, 1.6vw, 1.35rem);
  color: var(--charcoal-70);
  max-width: 640px;
}

.wrap {
  max-width: var(--container);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

section { padding: clamp(56px, 9vw, 120px) 0; }
.section-tight { padding: clamp(40px, 6vw, 72px) 0; }

.rule {
  border: none;
  border-top: 1px solid var(--line);
  margin: 0;
}

/* ---------- Nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(247, 238, 217, 0.92);
  backdrop-filter: blur(8px);
  border-top: 3px solid var(--olive);
  border-bottom: 1px solid var(--line);
}

.site-header .wrap { max-width: 1560px; }

.nav {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 34px;
  padding-bottom: 34px;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand {
  font-family: var(--font-display);
  font-size: 1.15rem;
  letter-spacing: 0.01em;
  text-decoration: none;
  color: var(--charcoal);
  white-space: nowrap;
}
.brand strong { font-weight: 600; }

.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(20px, 2.8vw, 44px);
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.nav-links li:last-child { margin-left: clamp(14px, 2.4vw, 34px); }

.nav-links li { white-space: nowrap; }

.nav-links a {
  text-decoration: none;
  color: var(--charcoal-70);
  transition: color 0.15s ease;
}
.nav-links a:hover,
.nav-links a[aria-current="page"] { color: var(--olive); }

.nav-cta {
  border: 1px solid var(--line-strong);
  padding: 8px 16px;
  border-radius: 2px;
  color: var(--charcoal) !important;
  font-weight: 600;
}
.nav-cta:hover { background: var(--charcoal); border-color: var(--charcoal); color: var(--cream) !important; }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--charcoal);
  margin: 5px 0;
}

@media (max-width: 780px) {
  .nav-toggle { display: block; }
  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--cream);
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    align-items: center;
    gap: 0;
    padding: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }
  .nav-links.open { max-height: 480px; padding: 28px var(--gutter) 36px; }
  .nav-links li { width: 100%; text-align: center; padding: 14px 0; }
  .nav-links a { font-size: 0.95rem; }
  .nav-cta { display: inline-block; margin-top: 10px; }
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  padding: 14px 26px;
  border-radius: 2px;
  border: 1px solid var(--charcoal);
  color: var(--charcoal);
  transition: all 0.18s ease;
}
.btn:hover { background: var(--charcoal); color: var(--cream); }

.btn-solid {
  background: var(--charcoal);
  color: var(--cream);
}
.btn-solid:hover { background: var(--clay-dark); border-color: var(--clay-dark); color: var(--cream); }

/* ---------- Hero ---------- */
.hero {
  padding-top: clamp(64px, 10vw, 120px);
  padding-bottom: clamp(56px, 8vw, 100px);
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: clamp(32px, 5vw, 64px);
  align-items: center;
}
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-grid .hero-media { order: -1; }
}
.hero-media img,
.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 2px;
}
.hero-media {
  aspect-ratio: 4 / 5;
  overflow: hidden;
  border-radius: 2px;
  background: var(--stone);
}

.cta-row { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 8px; }

/* ---------- Domain diagram ---------- */
.domain-diagram {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin: 48px 0;
}
@media (max-width: 780px) { .domain-diagram { grid-template-columns: 1fr; } }

.domain-card {
  border-top: 2px solid var(--gold-dark);
  padding: 34px 4px 4px;
}
.domain-card:nth-child(1) { border-top-color: var(--gold-dark); }
.domain-card:nth-child(2) { border-top-color: var(--clay-dark); }
.domain-card:nth-child(3) { border-top-color: var(--sage-dark); }
.domain-card:nth-child(1) .num { color: var(--gold-dark); }
.domain-card:nth-child(2) .num { color: var(--clay-dark); }
.domain-card:nth-child(3) .num { color: var(--sage-dark); }
.domain-card .num {
  font-family: var(--font-display);
  color: var(--clay-dark);
  font-size: 0.85rem;
  letter-spacing: 0.1em;
  display: block;
  margin-bottom: 14px;
}
.domain-card h3 { margin-bottom: 0.4em; }
.domain-card p { color: var(--charcoal-70); font-size: 0.98rem; margin-bottom: 0; }

.convergence {
  text-align: center;
  padding: 40px var(--gutter);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  margin: 8px 0 48px;
}
.convergence .domains-label {
  display: block;
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--charcoal-70);
}
.convergence .arrow {
  display: block;
  font-family: var(--font-display);
  color: var(--clay-dark);
  font-size: 1.1rem;
  margin: 14px 0;
}
.convergence strong {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  font-weight: 500;
  color: var(--charcoal);
}
.convergence .sub {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(1.15rem, 2vw, 1.4rem);
  font-weight: 500;
  color: var(--charcoal);
  margin-top: 6px;
}

/* ---------- Grid / cards ---------- */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(28px, 4vw, 60px); }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: clamp(24px, 3vw, 40px); }
@media (max-width: 860px) { .grid-2, .grid-3 { grid-template-columns: 1fr; } }

.card {
  background: rgba(255,255,255,0.4);
  padding: 36px 32px;
  border-radius: 2px;
}

.bg-stone { background: var(--stone); }
.bg-charcoal { background: var(--olive-dark); color: var(--cream); }
.bg-charcoal .charcoal-70 { color: rgba(242,236,222,0.72); }
.bg-charcoal .eyebrow { color: var(--gold); }
.bg-charcoal a.btn { border-color: var(--cream); color: var(--cream); }
.bg-charcoal a.btn:hover { background: var(--cream); color: var(--olive-dark); }

blockquote.pullquote {
  font-family: var(--font-display);
  font-size: clamp(1.3rem, 2.4vw, 1.85rem);
  font-weight: 480;
  line-height: 1.4;
  margin: 0;
  padding-left: clamp(20px, 3vw, 34px);
  border-left: 2px solid var(--clay);
}

.tag-list { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 10px; }
.tag-list li {
  font-size: 0.85rem;
  border: 1px solid var(--line-strong);
  padding: 6px 14px;
  border-radius: 20px;
  color: var(--charcoal-70);
}

.media-frame { border-radius: 2px; overflow: hidden; }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 48px 0 32px;
  margin-top: 40px;
}
.footer-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 28px;
  font-size: 0.9rem;
  color: var(--charcoal-70);
}
.footer-links { display: flex; gap: 22px; list-style: none; padding: 0; margin: 0; }
.footer-links a { text-decoration: none; color: var(--charcoal-70); }
.footer-links a:hover { color: var(--clay-dark); }
.footer-legal { margin-top: 28px; font-size: 0.8rem; color: var(--charcoal-45); line-height: 1.7; }

/* ---------- Forms ---------- */
form { max-width: 640px; }
.field { margin-bottom: 22px; }
label { display: block; font-size: 0.88rem; font-weight: 500; margin-bottom: 8px; }
input, select, textarea {
  width: 100%;
  font-family: var(--font-body);
  font-size: 1rem;
  padding: 13px 14px;
  border: 1px solid var(--line-strong);
  background: rgba(255,255,255,0.5);
  border-radius: 2px;
  color: var(--charcoal);
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--clay-dark);
}
textarea { resize: vertical; min-height: 140px; }

/* ---------- Utility ---------- */
.mt-0 { margin-top: 0; }
.center { text-align: center; }
.max-720 { max-width: 720px; }
.max-560 { max-width: 560px; }