:root, [data-theme='light'] {
  --color-bg: #f6f7f9;
  --color-surface: #fbfcfd;
  --color-surface-2: #ffffff;
  --color-surface-offset: #eef1f5;
  --color-surface-offset-2: #e5e9ef;
  --color-divider: #dde2e9;
  --color-border: #cfd6df;

  --color-text: #10151c;
  --color-text-muted: #59636f;
  --color-text-faint: #97a1ac;
  --color-text-inverse: #f6f7f9;

  --color-primary: #0d6e78;
  --color-primary-hover: #0a545c;
  --color-primary-active: #073d43;
  --color-primary-highlight: #cfe4e5;
  --color-signal: #17a2b8;

  --color-ink: #0b1622;
  --color-ink-2: #122031;

  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px rgba(16,21,28,0.06);
  --shadow-md: 0 6px 20px rgba(16,21,28,0.08);
  --shadow-lg: 0 18px 46px rgba(16,21,28,0.12);

  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.8125rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.3vw, 0.9375rem);
  --text-base: clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  --text-lg: clamp(1.125rem, 1rem + 0.6vw, 1.375rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.2vw, 2.1rem);
  --text-2xl: clamp(2rem, 1.3rem + 2.4vw, 3.25rem);
  --text-3xl: clamp(2.5rem, 1.2rem + 3.8vw, 4.25rem);

  --space-1: 0.25rem; --space-2: 0.5rem; --space-3: 0.75rem; --space-4: 1rem;
  --space-5: 1.25rem; --space-6: 1.5rem; --space-8: 2rem; --space-10: 2.5rem;
  --space-12: 3rem; --space-16: 4rem; --space-20: 5rem; --space-24: 6rem; --space-32: 8rem;

  --content-narrow: 680px;
  --content-default: 1000px;
  --content-wide: 1200px;

  --font-display: 'Newsreader', Georgia, serif;
  --font-body: 'General Sans', 'Inter', system-ui, sans-serif;
  --font-mono: 'IBM Plex Mono', ui-monospace, monospace;
}

[data-theme='dark'] {
  --color-bg: #0a0f16;
  --color-surface: #0e141d;
  --color-surface-2: #121a24;
  --color-surface-offset: #131c27;
  --color-surface-offset-2: #18222f;
  --color-divider: #1d2836;
  --color-border: #263341;

  --color-text: #dfe6ee;
  --color-text-muted: #8f9caa;
  --color-text-faint: #5c6875;
  --color-text-inverse: #0a0f16;

  --color-primary: #3fb3bd;
  --color-primary-hover: #5ac6cf;
  --color-primary-active: #78d4db;
  --color-primary-highlight: #123037;
  --color-signal: #33c0d4;

  --color-ink: #060b11;
  --color-ink-2: #0b131c;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.4);
  --shadow-md: 0 6px 20px rgba(0,0,0,0.5);
  --shadow-lg: 0 18px 46px rgba(0,0,0,0.6);
}

/* ---------- Layout primitives ---------- */
.wrap { width: 100%; max-width: var(--content-wide); margin-inline: auto; padding-inline: clamp(1.25rem, 4vw, 3rem); }
.narrow { max-width: var(--content-narrow); }
.default { max-width: var(--content-default); }

section { padding-block: clamp(var(--space-16), 9vw, var(--space-32)); }

.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-primary);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}
.eyebrow::before {
  content: "";
  width: 22px; height: 1px;
  background: var(--color-primary);
  display: inline-block;
}

h1, h2, h3 { font-family: var(--font-display); font-weight: 500; letter-spacing: -0.01em; }
.section-title { font-size: var(--text-xl); color: var(--color-text); margin-top: var(--space-4); }
.section-lead { font-size: var(--text-lg); color: var(--color-text-muted); max-width: 62ch; margin-top: var(--space-5); line-height: 1.5; }

/* ---------- Header ---------- */
.header {
  position: sticky; top: 0; z-index: 60;
  background: color-mix(in oklab, var(--color-bg) 88%, transparent);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s, box-shadow 0.3s;
}
.header--scrolled { border-bottom-color: var(--color-divider); box-shadow: var(--shadow-sm); }
.header__inner { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); height: 4.5rem; }
.brand { display: flex; align-items: center; gap: var(--space-3); color: var(--color-text); text-decoration: none; }
.brand__mark { color: var(--color-primary); flex-shrink: 0; }
.brand__name { font-family: var(--font-display); font-size: 1.15rem; font-weight: 600; letter-spacing: -0.01em; line-height: 1; }
.brand__name span { color: var(--color-primary); }
.brand__sub { display:block; font-family: var(--font-mono); font-size: 0.62rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--color-text-faint); margin-top: 3px; }

.nav { display: flex; align-items: center; gap: var(--space-6); }
.nav a { color: var(--color-text-muted); text-decoration: none; font-size: var(--text-sm); font-weight: 500; }
.nav a:hover { color: var(--color-text); }
.header__actions { display: flex; align-items: center; gap: var(--space-3); }

.theme-toggle {
  display: inline-grid; place-items: center; width: 40px; height: 40px;
  border-radius: var(--radius-full); color: var(--color-text-muted);
  border: 1px solid var(--color-border);
}
.theme-toggle:hover { color: var(--color-primary); border-color: var(--color-primary); }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  font-size: var(--text-sm); font-weight: 600; text-decoration: none;
  padding: 0.7rem 1.25rem; border-radius: var(--radius-full);
  border: 1px solid transparent; white-space: nowrap;
}
.btn--primary { background: var(--color-primary); color: #fff; }
[data-theme='dark'] .btn--primary { color: var(--color-ink); }
.btn--primary:hover { background: var(--color-primary-hover); transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn--ghost { border-color: var(--color-border); color: var(--color-text); background: var(--color-surface-2); }
.btn--ghost:hover { border-color: var(--color-primary); color: var(--color-primary); }
.btn--lg { padding: 0.9rem 1.6rem; font-size: var(--text-base); }

.nav-toggle { display: none; }

/* ---------- Hero ---------- */
.hero { position: relative; overflow: hidden; background: var(--color-ink); color: #eaf1f4; padding-block: clamp(5rem, 12vw, 9rem); border-bottom: 1px solid var(--color-border); }
.hero__grid { position: relative; z-index: 2; display: grid; grid-template-columns: 1.1fr 0.9fr; gap: clamp(2rem, 5vw, 4.5rem); align-items: center; }
.hero .eyebrow { color: var(--color-signal); }
.hero .eyebrow::before { background: var(--color-signal); }
.hero h1 { font-size: var(--text-3xl); color: #f4f8fa; line-height: 1.04; margin-top: var(--space-5); }
.hero h1 em { font-style: italic; color: var(--color-signal); }
.hero__lead { font-size: var(--text-lg); color: #aebecb; max-width: 54ch; margin-top: var(--space-6); line-height: 1.55; }
.hero__cta { display: flex; flex-wrap: wrap; gap: var(--space-3); margin-top: var(--space-8); }
.hero__cta .btn--ghost { background: transparent; color: #eaf1f4; border-color: rgba(255,255,255,0.22); }
.hero__cta .btn--ghost:hover { border-color: var(--color-signal); color: var(--color-signal); }
.hero__meta { display: flex; flex-wrap: wrap; gap: var(--space-5) var(--space-8); margin-top: var(--space-10); padding-top: var(--space-6); border-top: 1px solid rgba(255,255,255,0.1); }
.hero__meta div { display: flex; flex-direction: column; }
.hero__meta dt { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.14em; text-transform: uppercase; color: #6f8492; }
.hero__meta dd { font-family: var(--font-display); font-size: 1.35rem; color: #eaf1f4; margin-top: 4px; }
.hero__visual { position: relative; z-index: 2; }
.hero__visual svg { width: 100%; height: auto; filter: drop-shadow(0 8px 40px rgba(23,162,184,0.18)); }
.hero__bg { position: absolute; inset: 0; z-index: 1; opacity: 0.5; }
.hero__bg svg { width: 100%; height: 100%; }

/* connectivity node pulse */
.node { animation: pulse 4s ease-in-out infinite; }
.node:nth-child(2n) { animation-delay: 1.1s; }
.node:nth-child(3n) { animation-delay: 2.2s; }
@keyframes pulse { 0%,100% { opacity: 0.55; } 50% { opacity: 1; } }
.edge { stroke-dasharray: 4 6; animation: dash 6s linear infinite; }
@keyframes dash { to { stroke-dashoffset: -60; } }

/* ---------- Offers ---------- */
.offers__head { max-width: 60ch; }
.offer-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-6); margin-top: var(--space-12); }
.offer {
  background: var(--color-surface-2); border: 1px solid var(--color-border);
  border-radius: var(--radius-lg); padding: var(--space-8);
  display: flex; flex-direction: column; position: relative; overflow: hidden;
}
.offer::before { content: ""; position: absolute; top: 0; left: 0; right: 0; height: 3px; background: linear-gradient(90deg, var(--color-primary), var(--color-signal)); transform: scaleX(0); transform-origin: left; transition: transform 0.4s cubic-bezier(0.16,1,0.3,1); }
.offer:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: var(--color-primary); }
.offer:hover::before { transform: scaleX(1); }
.offer__num { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.14em; color: var(--color-primary); }
.offer__icon { width: 44px; height: 44px; color: var(--color-primary); margin-top: var(--space-4); }
.offer h3 { font-size: var(--text-lg); color: var(--color-text); margin-top: var(--space-5); line-height: 1.2; }
.offer p { color: var(--color-text-muted); font-size: var(--text-sm); margin-top: var(--space-4); line-height: 1.6; }
.offer__list { list-style: none; margin-top: var(--space-5); display: flex; flex-direction: column; gap: var(--space-3); }
.offer__list li { display: flex; gap: var(--space-3); font-size: var(--text-sm); color: var(--color-text); line-height: 1.45; }
.offer__list svg { color: var(--color-primary); flex-shrink: 0; margin-top: 3px; }
.offer__for { margin-top: auto; padding-top: var(--space-6); font-size: var(--text-xs); color: var(--color-text-faint); font-family: var(--font-mono); letter-spacing: 0.04em; }
.offer__for strong { color: var(--color-text-muted); font-weight: 500; }

/* ---------- Bio ---------- */
.bio { background: var(--color-surface-offset); border-block: 1px solid var(--color-divider); }
.bio__grid { display: grid; grid-template-columns: 0.85fr 1.15fr; gap: clamp(2rem, 5vw, 4.5rem); align-items: start; }
.bio__card { background: var(--color-ink); border-radius: var(--radius-lg); padding: var(--space-8); color: #eaf1f4; position: sticky; top: 6rem; }
.bio__portrait { width: 100%; aspect-ratio: 1; border-radius: var(--radius-md); background: linear-gradient(150deg, var(--color-ink-2), #0d2830); border: 1px solid rgba(255,255,255,0.08); display: grid; place-items: center; overflow: hidden; }
.bio__portrait svg { width: 68%; height: auto; color: var(--color-signal); }
.bio__name { font-family: var(--font-display); font-size: 1.5rem; margin-top: var(--space-6); color: #f4f8fa; }
.bio__role { font-size: var(--text-sm); color: #9db0bd; margin-top: var(--space-2); line-height: 1.5; }
.bio__creds { list-style: none; margin-top: var(--space-6); display: flex; flex-direction: column; gap: var(--space-3); }
.bio__creds li { font-size: var(--text-sm); color: #cdd9e1; display: flex; gap: var(--space-3); line-height: 1.4; }
.bio__creds svg { color: var(--color-signal); flex-shrink: 0; margin-top: 2px; }
.bio__body h2 { font-size: var(--text-xl); color: var(--color-text); }
.bio__body p { color: var(--color-text); font-size: var(--text-base); margin-top: var(--space-5); line-height: 1.7; max-width: 62ch; }
.bio__body p.muted { color: var(--color-text-muted); }
.pubs { margin-top: var(--space-8); display: flex; flex-direction: column; gap: var(--space-4); }
.pub { border-left: 2px solid var(--color-primary); padding: var(--space-1) 0 var(--space-1) var(--space-5); }
.pub__title { font-size: var(--text-sm); color: var(--color-text); font-weight: 600; line-height: 1.4; }
.pub__meta { font-size: var(--text-xs); color: var(--color-text-muted); margin-top: var(--space-2); font-family: var(--font-mono); }

/* ---------- Proof / connectivity figure ---------- */
.proof { background: var(--color-ink); color: #eaf1f4; border-block: 1px solid var(--color-divider); overflow: hidden; }
.proof__grid { display: grid; grid-template-columns: 0.85fr 1.15fr; gap: clamp(var(--space-8), 5vw, var(--space-16)); align-items: center; }
.proof .eyebrow { color: var(--color-signal); }
.proof .eyebrow::before { background: var(--color-signal); }
.proof__title { font-size: var(--text-xl); color: #f4f9fb; margin-top: var(--space-4); }
.proof__text p { color: rgba(234,241,244,0.72); margin-top: var(--space-5); font-size: var(--text-sm); line-height: 1.7; }
.proof__discipline { color: rgba(234,241,244,0.9) !important; border-left: 2px solid var(--color-signal); padding-left: var(--space-5); }
.proof__discipline strong { color: var(--color-signal); font-weight: 600; }
.proof__figure { margin: 0; }
.proof__figure img { width: 100%; height: auto; display: block; border-radius: var(--radius-md); }
.proof__figure figcaption { margin-top: var(--space-4); font-family: var(--font-mono); font-size: var(--text-xs); line-height: 1.6; color: rgba(234,241,244,0.5); letter-spacing: 0.01em; }

/* ---------- Use cases ---------- */
.cases__grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-6); margin-top: var(--space-12); }
.case {
  background: var(--color-surface-2); border: 1px solid var(--color-border);
  border-radius: var(--radius-lg); padding: var(--space-8); display: flex; flex-direction: column; gap: var(--space-4);
}
.case:hover { border-color: var(--color-primary); box-shadow: var(--shadow-md); }
.case__tag { align-self: flex-start; font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.1em; text-transform: uppercase; color: var(--color-primary); background: var(--color-primary-highlight); padding: 0.3rem 0.7rem; border-radius: var(--radius-full); }
.case h3 { font-family: var(--font-body); font-weight: 600; font-size: var(--text-base); color: var(--color-text); line-height: 1.35; }
.case__scenario { font-size: var(--text-sm); color: var(--color-text-muted); line-height: 1.6; }
.case__outcome { font-size: var(--text-sm); color: var(--color-text); line-height: 1.6; padding-top: var(--space-4); border-top: 1px dashed var(--color-divider); }
.case__outcome strong { color: var(--color-primary); font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.08em; text-transform: uppercase; display: block; margin-bottom: var(--space-2); }

/* ---------- Methods / governed workflows ---------- */
.methods { background: var(--color-ink); color: #eaf1f4; border-block: 1px solid var(--color-divider); }
.methods__grid { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: clamp(var(--space-8), 5vw, var(--space-16)); align-items: center; }
.methods .eyebrow { color: var(--color-signal); }
.methods .eyebrow::before { background: var(--color-signal); }
.methods__text .section-title { color: #f4f9fb; }
.methods__text p { color: rgba(234,241,244,0.74); font-size: var(--text-base); margin-top: var(--space-5); line-height: 1.7; max-width: 60ch; }
.methods__note { color: rgba(234,241,244,0.9) !important; border-left: 2px solid var(--color-signal); padding-left: var(--space-5); font-size: var(--text-sm) !important; }
.methods__text .btn--ghost { margin-top: var(--space-7); color: #eaf1f4; border-color: rgba(255,255,255,0.24); background: transparent; }
.methods__text .btn--ghost:hover { border-color: var(--color-signal); color: var(--color-signal); }
.methods__list { list-style: none; display: flex; flex-direction: column; gap: var(--space-4); }
.methods__list li { border: 1px solid rgba(255,255,255,0.1); border-radius: var(--radius-md); padding: var(--space-5) var(--space-6); background: rgba(255,255,255,0.02); }
.methods__k { display: block; font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.1em; text-transform: uppercase; color: var(--color-signal); }
.methods__v { display: block; margin-top: var(--space-2); font-size: var(--text-sm); color: rgba(234,241,244,0.7); line-height: 1.55; }

/* ---------- How it works ---------- */
.how { background: var(--color-surface-offset); border-block: 1px solid var(--color-divider); }
.how__grid { display: grid; grid-template-columns: repeat(3,1fr); gap: var(--space-8); margin-top: var(--space-12); counter-reset: step; }
.how__step { position: relative; padding-top: var(--space-6); border-top: 2px solid var(--color-primary); }
.how__step::before { counter-increment: step; content: counter(step,decimal-leading-zero); font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-primary); letter-spacing: 0.1em; }
.how__step h3 { font-family: var(--font-body); font-weight: 600; font-size: var(--text-base); color: var(--color-text); margin-top: var(--space-2); }
.how__step p { font-size: var(--text-sm); color: var(--color-text-muted); margin-top: var(--space-3); line-height: 1.6; }

/* ---------- Contact ---------- */
.contact { background: var(--color-ink); color: #eaf1f4; }
.contact__grid { display: grid; grid-template-columns: 0.95fr 1.05fr; gap: clamp(2rem,5vw,4.5rem); align-items: start; }
.contact .eyebrow { color: var(--color-signal); }
.contact .eyebrow::before { background: var(--color-signal); }
.contact h2 { font-size: var(--text-2xl); color: #f4f8fa; margin-top: var(--space-4); line-height: 1.08; }
.contact__lead { color: #aebecb; font-size: var(--text-base); margin-top: var(--space-5); line-height: 1.65; max-width: 46ch; }
.contact__points { list-style: none; margin-top: var(--space-8); display: flex; flex-direction: column; gap: var(--space-4); }
.contact__points li { display: flex; gap: var(--space-3); font-size: var(--text-sm); color: #cdd9e1; }
.contact__points svg { color: var(--color-signal); flex-shrink: 0; margin-top: 2px; }

.form { background: var(--color-surface-2); border: 1px solid var(--color-border); border-radius: var(--radius-lg); padding: clamp(1.5rem, 3vw, 2.5rem); }
.form__row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }
.field { margin-bottom: var(--space-5); }
.field label { display: block; font-size: var(--text-sm); font-weight: 600; color: var(--color-text); margin-bottom: var(--space-2); }
.field label span { color: var(--color-primary); }
.field input, .field select, .field textarea {
  width: 100%; padding: 0.75rem 0.9rem; border: 1px solid var(--color-border);
  border-radius: var(--radius-md); background: var(--color-surface); color: var(--color-text); font-size: var(--text-sm);
}
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--color-primary); outline: none; box-shadow: 0 0 0 3px var(--color-primary-highlight); }
.field textarea { resize: vertical; min-height: 120px; }
.form__note { font-size: var(--text-xs); color: var(--color-text-muted); margin-top: var(--space-4); line-height: 1.5; }
.form button[type=submit] { width: 100%; margin-top: var(--space-2); }
.form__success { display: none; text-align: center; padding: var(--space-8) var(--space-4); }
.form__success svg { color: var(--color-primary); margin: 0 auto var(--space-4); }
.form__success h3 { font-family: var(--font-body); font-weight: 600; font-size: var(--text-lg); color: var(--color-text); }
.form__success p { font-size: var(--text-sm); color: var(--color-text-muted); margin-top: var(--space-3); }
.form.sent .form__body { display: none; }
.form.sent .form__success { display: block; }

/* ---------- Footer ---------- */
.footer { background: var(--color-surface); border-top: 1px solid var(--color-divider); padding-block: var(--space-12); }
.footer__inner { display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--space-8); align-items: flex-start; }
.footer__brand { max-width: 34ch; }
.footer__brand p { font-size: var(--text-sm); color: var(--color-text-muted); margin-top: var(--space-4); line-height: 1.6; }
.footer__wrapper { display: flex; align-items: center; gap: var(--space-3); margin-top: var(--space-5); }
.footer__wrapper-logo { width: 40px; height: 40px; border-radius: var(--radius-sm); flex-shrink: 0; opacity: 0.9; }
.footer__wrapper-note { font-family: var(--font-mono); font-size: var(--text-xs); color: var(--color-text-faint); letter-spacing: 0.02em; line-height: 1.5; }
.footer__links { display: flex; gap: var(--space-16); flex-wrap: wrap; }
.footer__col h4 { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.14em; text-transform: uppercase; color: var(--color-text-faint); }
.footer__col ul { list-style: none; margin-top: var(--space-4); display: flex; flex-direction: column; gap: var(--space-3); }
.footer__col a { color: var(--color-text-muted); text-decoration: none; font-size: var(--text-sm); }
.footer__col a:hover { color: var(--color-primary); }
.footer__legal { width: 100%; margin-top: var(--space-10); padding-top: var(--space-6); border-top: 1px solid var(--color-divider); font-size: var(--text-xs); color: var(--color-text-faint); display: flex; flex-wrap: wrap; gap: var(--space-4); justify-content: space-between; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .hero__grid, .bio__grid, .contact__grid, .proof__grid { grid-template-columns: 1fr; }
  .hero__visual { order: -1; max-width: 420px; margin-inline: auto; }
  .proof__figure { order: -1; }
  .methods__grid { grid-template-columns: 1fr; }
  .bio__card { position: static; }
  .offer-grid, .how__grid { grid-template-columns: 1fr; }
  .cases__grid { grid-template-columns: 1fr; }
  .nav { display: none; }
  .nav-toggle { display: inline-grid; place-items: center; width: 40px; height: 40px; border-radius: var(--radius-full); border: 1px solid var(--color-border); color: var(--color-text); }
  .nav--open { display: flex; position: absolute; top: 4.5rem; left: 0; right: 0; flex-direction: column; align-items: stretch; gap: 0; background: var(--color-surface-2); border-bottom: 1px solid var(--color-divider); padding: var(--space-4); box-shadow: var(--shadow-md); }
  .nav--open a { padding: var(--space-3) var(--space-2); }
}
@media (max-width: 560px) {
  .form__row { grid-template-columns: 1fr; }
  .hero__cta { flex-direction: column; align-items: stretch; }
  .hero__cta .btn { width: 100%; }
  .header__inner { gap: var(--space-2); }
  .brand__name { font-size: 1rem; white-space: nowrap; }
  .brand__sub { display: none; }
  .header__actions .btn--primary { display: none; }
  .theme-toggle { width: 38px; height: 38px; }
}