/* ============================================================
   quGradient · components
   Same class vocabulary as quMatrix (drop-in markup), reskinned
   for a light-first, gradient brand. Nav · footer · buttons ·
   labels · stat callouts · cards · product cards · badges.
   ============================================================ */

/* --- section label (eyebrow) ------------------------------- */
.label {
  display: inline-flex; align-items: center; gap: var(--s-2);
  font-family: var(--font-mono);
  font-size: var(--fs-label); font-weight: 500;
  letter-spacing: var(--tracking-label); text-transform: uppercase;
  color: var(--brand-ink);
  margin: 0 0 var(--s-4);
}
.label::before {
  content: ""; width: 2rem; height: 2px; border-radius: 2px;
  background: var(--grad);
}
.label--plain::before { background: currentColor; opacity: 0.6; }
.on-dark .label { color: var(--brand-2); }
.center .label { justify-content: center; }

/* --- buttons ----------------------------------------------- */
.btn {
  --btn-bg: var(--ink);
  --btn-ink: var(--white);
  display: inline-flex; align-items: center; gap: var(--s-2);
  padding: 0.85em 1.5em;
  font-family: var(--font-sans); font-size: var(--fs-sm);
  font-weight: 600; letter-spacing: 0.01em; line-height: 1;
  color: var(--btn-ink); background: var(--btn-bg);
  border: 1px solid transparent;
  border-radius: var(--r-pill); cursor: pointer;
  transition: transform var(--dur) var(--ease-out),
              box-shadow var(--dur) var(--ease),
              filter var(--dur) var(--ease),
              background var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}
.btn:hover { transform: translateY(-1px); box-shadow: var(--shadow-md); text-decoration: none; }
.btn:active { transform: translateY(0); }
.btn .arrow { transition: transform var(--dur) var(--ease-out); }
.btn:hover .arrow { transform: translateX(3px); }

.btn--primary {                 /* Quantum Cyan gradient — primary CTA */
  --btn-ink: var(--navy);
  background: var(--grad);
  background-size: 140% 140%;
  box-shadow: var(--shadow-brand);
}
.btn--primary:hover { color: var(--navy); filter: saturate(1.06) brightness(1.03); box-shadow: 0 14px 40px rgba(0,217,255,0.38); }

.btn--secondary {               /* outline on light */
  --btn-bg: transparent; --btn-ink: var(--ink);
  border-color: var(--border);
}
.btn--secondary:hover { border-color: var(--brand); color: var(--brand-ink); }

.btn--ghost-dark {              /* outline on dark bands */
  --btn-bg: transparent; --btn-ink: var(--white);
  border-color: var(--white-14);
}
.btn--ghost-dark:hover { border-color: var(--brand-2); color: var(--brand-2); }

.btn--lg { padding: 1.05em 1.8em; font-size: var(--fs-body); }

.on-dark .btn { color: var(--btn-ink); }
.on-dark .btn--ghost-dark:hover { color: var(--brand-2); }

/* text link with arrow */
.link-arrow {
  display: inline-flex; align-items: center; gap: 0.4em;
  font-weight: 600; font-size: var(--fs-sm); color: var(--brand-ink);
}
.link-arrow .arrow { transition: transform var(--dur) var(--ease-out); }
.link-arrow:hover { text-decoration: none; color: var(--brand); }
.link-arrow:hover .arrow { transform: translateX(3px); }

/* --- stat callout ------------------------------------------ */
.stat { display: flex; flex-direction: column; gap: var(--s-1); }
.stat__num {
  font-family: var(--font-display); font-size: var(--fs-stat);
  font-weight: 700; line-height: 1; letter-spacing: -0.03em;
  color: var(--ink);
}
.stat__num.grad-text { font-weight: 700; }
.on-dark .stat__num { color: var(--white); }
.stat__num .unit { background: var(--grad); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.stat__label { font-size: var(--fs-sm); color: var(--muted); max-width: 24ch; }
.on-dark .stat__label { color: var(--on-dark-muted); }
.stat-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: var(--s-6) var(--s-5); }

/* --- card -------------------------------------------------- */
.card {
  position: relative; background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--r-lg); padding: var(--s-6);
  box-shadow: var(--shadow-sm);
  transition: transform var(--dur) var(--ease-out),
              box-shadow var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}
.card::before {
  content: ""; position: absolute; inset: 0 0 auto 0; height: 3px;
  background: var(--grad); opacity: 0;
  border-radius: var(--r-lg) var(--r-lg) 0 0;
  transition: opacity var(--dur) var(--ease);
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--brand-20); }
.card:hover::before { opacity: 1; }
.card--flat:hover { transform: none; box-shadow: var(--shadow-sm); }

.card__icon {
  width: 46px; height: 46px; padding: 11px;
  border-radius: 13px; background: var(--grad-soft); color: var(--brand);
  margin-bottom: var(--s-4);
  transition: transform var(--dur) var(--ease-out);
}
.card:hover .card__icon { transform: translateY(-1px) scale(1.05); }
.card__title { margin-bottom: var(--s-2); }
.card__title.h4 { font-family: var(--font-display); font-size: var(--fs-h4); color: var(--ink); }
.card__body { font-size: var(--fs-sm); color: var(--muted); margin-bottom: var(--s-4); }
.card__body:last-child { margin-bottom: 0; }

/* generic responsive grids */
.grid { display: grid; gap: var(--s-5); }
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); }
.grid--4 { grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); }

/* --- maturity badge (editorial guardrail §11.4) ------------ */
.badge {
  display: inline-flex; align-items: center; gap: 0.45em;
  padding: 0.3em 0.75em;
  font-family: var(--font-mono); font-size: var(--fs-xs);
  font-weight: 500; letter-spacing: 0.04em; text-transform: uppercase;
  border-radius: var(--r-pill); border: 1px solid var(--border);
  color: var(--muted); background: var(--soft);
}
.badge::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: currentColor; }
.badge--beta     { color: #b26a00; background: #fff6e6; border-color: #f3d9a6; }
.badge--preview  { color: var(--brand-ink); background: var(--brand-12); border-color: transparent; }
.badge--research { color: #0e8a9c; background: var(--cyan-12); border-color: transparent; }
.badge--ga       { color: #0e8a9c; }
.badge--prelim   { color: var(--muted); }
.badge--on-dark  { background: var(--white-08); border-color: var(--white-14); color: var(--on-dark-ink); }

/* --- product card ------------------------------------------ */
.pcard {
  position: relative; display: flex; flex-direction: column;
  background: var(--white); border: 1px solid var(--border);
  border-radius: var(--r-lg); padding: var(--s-6);
  box-shadow: var(--shadow-sm);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease);
}
.pcard:hover { border-color: var(--brand-20); transform: translateY(-4px); box-shadow: var(--shadow-md); }
.pcard--lead {
  border-color: transparent;
  background:
    linear-gradient(var(--white), var(--white)) padding-box,
    var(--grad) border-box;
  border: 1.5px solid transparent;
  box-shadow: var(--shadow-md);
}
.pcard__name { font-family: var(--font-display); font-size: var(--fs-h4); color: var(--ink); margin: 0 0 var(--s-2); }
.pcard__name .iq { background: var(--grad); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.pcard__desc { font-size: var(--fs-sm); color: var(--muted); margin: 0 0 var(--s-4); flex: 1; }
.pcard__foot { display: flex; flex-wrap: wrap; gap: var(--s-2); align-items: center; }

/* --- brand wordmark (no logo asset yet) -------------------- */
.brand__mark {
  font-family: var(--font-display); font-weight: 700;
  font-size: 1.3rem; letter-spacing: -0.03em; color: var(--ink);
  display: inline-flex; align-items: center;
}
.brand__mark .g { background: var(--grad); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.brand__dot { width: 8px; height: 8px; border-radius: 50%; background: var(--grad); margin-right: 0.55em; box-shadow: var(--shadow-brand); }
.brand__nabla { display: inline-block; width: 0.72em; height: 0.70em; margin: 0 0.02em; background: var(--grad); clip-path: polygon(0 0, 100% 0, 50% 100%); vertical-align: baseline; }
.on-dark .brand__mark, .site-header .brand__mark, .site-footer .brand__mark { color: var(--white); }

/* --- site header / nav (light, glass) ---------------------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(10, 31, 68, 0.82);
  backdrop-filter: saturate(140%) blur(12px);
  border-bottom: 1px solid var(--white-08);
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.site-header.is-scrolled {
  background: rgba(7, 18, 40, 0.94);
  box-shadow: 0 10px 34px rgba(4, 11, 26, 0.45);
  border-bottom-color: rgba(0, 217, 255, 0.12);
}
.nav { display: flex; align-items: center; gap: var(--s-6); height: 66px; }
.nav__brand { display: flex; align-items: center; }
.nav__links {
  display: flex; align-items: center;
  gap: clamp(1rem, 0.3rem + 1.5vw, 2.1rem);
  list-style: none; margin: 0 0 0 var(--s-6); padding: 0;
}
.nav__links a {
  font-size: var(--fs-sm); font-weight: 500; color: rgba(255,255,255,0.76);
  padding-block: 0.55em; position: relative;
  transition: color var(--dur) var(--ease);
}
.nav__links a:hover, .nav__links a[aria-current="page"] { color: #fff; text-decoration: none; }
.nav__links a::after {
  content: ""; position: absolute; left: 0; right: 100%; bottom: -1px;
  height: 2px; border-radius: 2px; background: var(--grad);
  transition: right var(--dur) var(--ease-out);
}
.nav__links a:hover::after, .nav__links a[aria-current="page"]::after { right: 0; }
.nav__cta { display: flex; align-items: center; gap: var(--s-4); margin-left: auto; }
.nav__toggle { display: none; }

@media (max-width: 900px) {
  .nav__links, .nav__cta .btn { display: none; }
  .nav__toggle {
    display: inline-flex; background: none; border: 0; cursor: pointer;
    color: var(--white); padding: var(--s-2);
  }
}

/* --- mobile nav drawer ------------------------------------- */
.nav-drawer { display: none; }
.nav-drawer[data-open="true"] {
  display: block; position: fixed; inset: 67px 0 0; z-index: 49;
  background: var(--navy-950); padding: var(--s-6) var(--gutter);
  border-top: 1px solid var(--white-08);
}
.nav-drawer ul { list-style: none; margin: 0 0 var(--s-6); padding: 0; display: grid; gap: var(--s-2); }
.nav-drawer a { display: block; padding: var(--s-3) 0; color: var(--white); font-size: var(--fs-h4); font-family: var(--font-display); border-bottom: 1px solid var(--white-08); }

/* --- footer (dark gradient) -------------------------------- */
.site-footer {
  position: relative;
  background: radial-gradient(80% 130% at 88% -20%, rgba(110,86,248,0.22), transparent 55%),
              linear-gradient(180deg, var(--dark-2) 0%, var(--dark) 100%);
  color: var(--on-dark-muted);
  padding-block: var(--s-9) var(--s-6);
  border-top: 1px solid var(--white-08);
}
.site-footer::before {
  content: ""; position: absolute; top: -1px; left: 0; right: 0; height: 2px;
  background: var(--grad);
}
.footer-grid { display: grid; gap: var(--s-6); grid-template-columns: 1.5fr repeat(4, 1fr); }
@media (max-width: 900px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
.footer-col h5 {
  font-family: var(--font-sans); font-size: var(--fs-xs); font-weight: 600;
  letter-spacing: var(--tracking-label); text-transform: uppercase;
  color: var(--on-dark-ink); margin: 0 0 var(--s-4);
}
.footer-col ul { list-style: none; margin: 0; padding: 0; display: grid; gap: var(--s-3); }
.footer-col a { font-size: var(--fs-sm); color: var(--on-dark-muted); }
.footer-col a:hover { color: var(--brand-2); text-decoration: none; }
.footer-brand p { font-size: var(--fs-sm); color: var(--on-dark-muted); max-width: 36ch; margin-top: var(--s-4); }
.footer-bottom {
  display: flex; flex-wrap: wrap; gap: var(--s-4); justify-content: space-between;
  margin-top: var(--s-7); padding-top: var(--s-5);
  border-top: 1px solid var(--white-08);
  font-size: var(--fs-xs); color: var(--on-dark-muted);
}