/* Severus Technology — design system
   Light corporate theme, teal accent. Semantic tokens only; no raw hex in components. */

:root {
  --bg: #f6f8fa;
  --surface: #ffffff;
  --surface-2: #edf1f5;
  --border: #dce3eb;
  --border-strong: #c2cdda;
  --text: #16232f;
  --text-muted: #4c5f72;
  --text-faint: #5f7183;
  --accent: #0f766e;
  --accent-strong: #0d9488;
  --accent-dim: rgba(15, 118, 110, 0.07);
  --accent-border: rgba(15, 118, 110, 0.35);
  --font-sans: ui-sans-serif, system-ui, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "Cascadia Code", "Segoe UI Mono", Consolas, Menlo, monospace;
  --radius: 10px;
  --container: 72rem;
  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.5rem;
  --space-4: 2rem;
  --space-5: 3rem;
  --space-6: 5rem;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

main { flex: 1; }

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

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-strong); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--accent);
  color: var(--bg);
  padding: 0.6rem 1rem;
  z-index: 200;
  font-weight: 600;
}
.skip-link:focus { left: 1rem; top: 1rem; color: var(--bg); }

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--space-3);
}

/* ---------- Header / nav ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 4.25rem;
  gap: var(--space-2);
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  color: var(--text);
  font-weight: 700;
  letter-spacing: 0.12em;
  font-size: 1.05rem;
}
.brand:hover { color: var(--text); }
.brand .dot { color: var(--accent); }
.brand small {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 400;
  letter-spacing: 0.28em;
  color: var(--text-faint);
  text-transform: uppercase;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
}

.nav-links a {
  display: inline-block;
  padding: 0.55rem 0.9rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: 8px;
  transition: color 150ms ease, background-color 150ms ease;
}
.nav-links a:hover { color: var(--text); background: var(--surface-2); }
.nav-links a[aria-current="page"] { color: var(--accent); }

.nav-cta {
  border: 1px solid var(--accent-border);
  color: var(--accent);
}
.nav-links a.nav-cta:hover { background: var(--accent-dim); color: var(--accent-strong); }

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  width: 44px;
  height: 44px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
}
.nav-toggle svg { width: 22px; height: 22px; }
.nav-toggle .icon-close { display: none; }
.nav-toggle[aria-expanded="true"] .icon-open { display: none; }
.nav-toggle[aria-expanded="true"] .icon-close { display: block; }

/* ---------- Hero ---------- */

.hero {
  position: relative;
  padding-block: var(--space-6) var(--space-6);
  overflow: hidden;
  background:
    radial-gradient(55rem 30rem at 80% 0%, rgba(13, 148, 136, 0.09), transparent 62%),
    radial-gradient(40rem 24rem at 0% 100%, rgba(13, 148, 136, 0.05), transparent 60%);
  border-bottom: 1px solid var(--border);
}

.hero-inner { max-width: 50rem; }

.hero-split {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: var(--space-5);
  align-items: center;
}

.hero-art { width: 100%; height: auto; }
.hero-art-sm { max-width: 26rem; justify-self: end; }

@media (max-width: 900px) {
  .hero-split { grid-template-columns: 1fr; }
  .hero-art { max-width: 26rem; justify-self: start; }
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--space-2);
}

h1 {
  font-size: clamp(2.2rem, 5.5vw, 3.6rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  font-weight: 750;
  margin-bottom: var(--space-3);
}

.hero p.lede {
  font-size: 1.15rem;
  color: var(--text-muted);
  max-width: 40rem;
  margin-bottom: var(--space-4);
}

.btn-row { display: flex; flex-wrap: wrap; gap: var(--space-2); }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.8rem 1.5rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 1rem;
  min-height: 44px;
  cursor: pointer;
  transition: background-color 150ms ease, color 150ms ease, border-color 150ms ease, transform 150ms ease;
  border: 1px solid transparent;
}
.btn:active { transform: scale(0.98); }

.btn-primary { background: var(--accent); color: #ffffff; }
.btn-primary:hover { background: var(--accent-strong); color: #ffffff; }

.btn-ghost { border-color: var(--border-strong); color: var(--text); }
.btn-ghost:hover { border-color: var(--accent-border); color: var(--accent); }

/* ---------- Sections ---------- */

.section { padding-block: var(--space-6); }
.section + .section { border-top: 1px solid var(--border); }
.section-alt { background: var(--surface); }

.section-head { max-width: 44rem; margin-bottom: var(--space-5); }

h2 {
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
  letter-spacing: -0.015em;
  line-height: 1.2;
  margin-bottom: var(--space-2);
}

.section-head p { color: var(--text-muted); font-size: 1.05rem; }

h3 { font-size: 1.15rem; letter-spacing: -0.01em; }

/* ---------- Cards & grids ---------- */

.grid {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: repeat(auto-fill, minmax(17rem, 1fr));
}

.grid-4 { grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr)); }
.grid-2 { grid-template-columns: repeat(auto-fill, minmax(24rem, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fill, minmax(19rem, 1fr)); }

.badge {
  display: inline-block;
  vertical-align: middle;
  margin-left: 0.4rem;
  font-family: var(--font-mono);
  font-size: 0.66rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  border-radius: 999px;
  padding: 0.18rem 0.6rem;
  white-space: nowrap;
}

.product-note {
  margin-top: var(--space-4);
  color: var(--text-muted);
  max-width: 44rem;
}

.card ul {
  list-style: none;
  display: grid;
  gap: 0.55rem;
  color: var(--text-muted);
  font-size: 0.96rem;
}
.card ul li { position: relative; padding-left: 1.3rem; }
.card ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.7;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  box-shadow: 0 1px 3px rgba(16, 35, 47, 0.06);
  transition: border-color 150ms ease, transform 150ms ease;
}
.section-alt .card { background: var(--surface-2); }
.card:hover { border-color: var(--accent-border); }

.card .card-icon {
  width: 44px;
  height: 44px;
  border-radius: 8px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
}
.card .card-icon svg { width: 22px; height: 22px; }

.card p { color: var(--text-muted); font-size: 0.96rem; }

.tag-row { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-top: auto; padding-top: var(--space-1); }

.tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.03em;
  color: var(--text-muted);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.2rem 0.65rem;
  white-space: nowrap;
}

/* ---------- Client cards ---------- */

.client-card .client-top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.client-sector {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
}

.client-period {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-faint);
}

.client-featured { border-color: var(--accent-border); background: linear-gradient(180deg, var(--accent-dim), transparent 40%), var(--surface); }

/* ---------- Logo strip ---------- */

.logo-strip {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  align-items: center;
}

.logo-strip span {
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.06em;
  color: var(--text-faint);
  text-transform: uppercase;
  transition: color 150ms ease;
}
.logo-strip span:hover { color: var(--text-muted); }

/* ---------- Stats ---------- */

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr));
  gap: var(--space-3);
}

.stat {
  border-left: 2px solid var(--accent);
  padding-left: var(--space-2);
}
.stat .num {
  display: block;
  font-size: 2rem;
  font-weight: 750;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}
.stat .label { color: var(--text-muted); font-size: 0.92rem; }

/* ---------- Prose / about ---------- */

.split-2 {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: var(--space-5);
  align-items: center;
}
@media (max-width: 900px) {
  .split-2 { grid-template-columns: 1fr; }
}

.prose { max-width: 44rem; }
.prose p { color: var(--text-muted); margin-bottom: var(--space-2); }
.prose p strong { color: var(--text); }

/* ---------- Steps (how we work) ---------- */

.steps { counter-reset: step; display: grid; gap: var(--space-3); grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr)); }

.step { counter-increment: step; }
.step::before {
  content: "0" counter(step);
  font-family: var(--font-mono);
  color: var(--accent);
  font-size: 0.9rem;
  letter-spacing: 0.1em;
  display: block;
  margin-bottom: var(--space-1);
}
.step h3 { margin-bottom: 0.35rem; }
.step p { color: var(--text-muted); font-size: 0.96rem; }

/* ---------- Contact ---------- */

.contact-list { list-style: none; display: grid; gap: var(--space-2); max-width: 34rem; }

.contact-list a.contact-item { color: var(--text); }

.contact-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: var(--space-2) var(--space-3);
  transition: border-color 150ms ease;
}
a.contact-item:hover { border-color: var(--accent-border); }
.contact-item svg { width: 22px; height: 22px; color: var(--accent); flex-shrink: 0; }
.contact-item .sub { color: var(--text-faint); font-size: 0.88rem; display: block; }

/* ---------- CTA band ---------- */

.cta-band {
  text-align: center;
  padding-block: var(--space-6);
  background:
    radial-gradient(40rem 18rem at 50% 120%, rgba(13, 148, 136, 0.09), transparent 70%),
    var(--surface);
  border-top: 1px solid var(--border);
}
.cta-band h2 { margin-bottom: var(--space-2); }
.cta-band p { color: var(--text-muted); margin-bottom: var(--space-4); }
.cta-band .btn-row { justify-content: center; }

/* ---------- Footer ---------- */

.site-footer {
  border-top: 1px solid var(--border);
  padding-block: var(--space-4);
  font-size: 0.9rem;
  color: var(--text-faint);
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  align-items: center;
  justify-content: space-between;
}
.footer-links { display: flex; flex-wrap: wrap; gap: var(--space-2); list-style: none; }
.footer-links a { color: var(--text-muted); }
.footer-links a:hover { color: var(--accent); }

/* ---------- Page hero (inner pages) ---------- */

.page-hero {
  padding-block: var(--space-5);
  border-bottom: 1px solid var(--border);
  background: radial-gradient(50rem 20rem at 80% -30%, rgba(13, 148, 136, 0.06), transparent 60%);
}
.page-hero h1 { font-size: clamp(1.9rem, 4.5vw, 2.8rem); margin-bottom: var(--space-2); }
.page-hero p { color: var(--text-muted); max-width: 44rem; font-size: 1.08rem; }

/* ---------- Reveal animation ---------- */

@media (prefers-reduced-motion: no-preference) {
  .reveal {
    opacity: 0;
    transform: translateY(14px);
    transition: opacity 400ms ease-out, transform 400ms ease-out;
  }
  .reveal.is-visible { opacity: 1; transform: none; }
}

/* ---------- Mobile ---------- */

@media (max-width: 768px) {
  .nav-toggle { display: flex; }

  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: var(--space-2) var(--space-3) var(--space-3);
    gap: 0.25rem;
  }
  .nav-links.is-open { display: flex; }
  .nav-links a { padding: 0.85rem 1rem; font-size: 1.05rem; }

  .hero { padding-block: var(--space-5); }
  .section { padding-block: var(--space-5); }

}