.sb-header{position:sticky;top:0;z-index:40;background:rgba(248,250,252,0.96);backdrop-filter:blur(16px);border-bottom:1px solid var(--color-border)}.sb-header__inner{display:flex;align-items:center;justify-content:space-between;padding-top:0.75rem;padding-bottom:0.75rem;gap:1rem}.sb-header__brand{display:inline-flex;align-items:center;gap:0.7rem;color:var(--color-text)}.sb-header__brand:hover{color:var(--color-text)}.sb-header__logo-mark{position:relative;width:40px;height:40px;border-radius:999px;background:radial-gradient(circle at 30% 20%,#e0f2fe 0,#38bdf8 40%,#1d4ed8 100%);box-shadow:0 8px 18px rgba(15,23,42,0.22);display:flex;align-items:center;justify-content:center;overflow:hidden}.sb-header__logo-bubble{position:absolute;border-radius:999px;opacity:0.96}.sb-header__logo-bubble--blue{width:18px;height:18px;top:6px;left:6px;background:radial-gradient(circle at 20% 15%,#f9fafb 0,#0ea5e9 40%,#0369a1 100%)}.sb-header__logo-bubble--purple{width:14px;height:14px;bottom:6px;right:6px;background:radial-gradient(circle at 20% 15%,#fdf2ff 0,#8b5cf6 40%,#4c1d95 100%)}.sb-header__brand-text{display:flex;flex-direction:column;line-height:1.1}.sb-header__site-name{font-family:var(--font-display);font-size:1.25rem;letter-spacing:-0.03em}.sb-header__site-tagline{font-family:var(--font-sans);font-size:0.75rem;color:var(--color-text-muted)}.sb-header__nav{display:flex;align-items:center}.sb-header__nav-list{display:flex;align-items:center;gap:0.5rem}.sb-header__nav-link{display:inline-flex;align-items:center;padding:0.45rem 0.9rem;border-radius:999px;font-family:var(--font-sans);font-size:0.85rem;font-weight:500;color:var(--color-text-muted)}.sb-header__nav-link:hover,.sb-header__nav-link:focus-visible{color:var(--color-text);background:rgba(148,163,184,0.12)}.sb-header__nav-item--cta .sb-header__nav-link--cta{background:linear-gradient(135deg,var(--color-primary),var(--color-accent));color:#f9fafb;box-shadow:0 10px 24px rgba(37,99,235,0.28)}.sb-header__nav-item--cta .sb-header__nav-link--cta:hover,.sb-header__nav-item--cta .sb-header__nav-link--cta:focus-visible{color:#f9fafb;transform:translateY(-1px);box-shadow:0 14px 32px rgba(37,99,235,0.38)}.sb-header__nav-toggle{display:none;flex-direction:column;align-items:center;justify-content:center;width:44px;height:44px;flex-shrink:0;border-radius:999px;border:1px solid var(--color-border);background:#ffffff;color:var(--color-text);padding:0;gap:5px}.sb-header__nav-toggle-bar{display:block;width:18px;height:2px;margin:0;border-radius:999px;background:var(--color-text);transition:transform var(--transition-fast),opacity var(--transition-fast),background-color var(--transition-fast)}.sb-header__nav-toggle:focus-visible{outline:2px solid var(--color-accent);outline-offset:3px}.sb-header__nav-toggle[aria-expanded="true"] .sb-header__nav-toggle-bar:nth-child(1){transform:translateY(7px) rotate(45deg)}.sb-header__nav-toggle[aria-expanded="true"] .sb-header__nav-toggle-bar:nth-child(2){opacity:0}.sb-header__nav-toggle[aria-expanded="true"] .sb-header__nav-toggle-bar:nth-child(3){transform:translateY(-7px) rotate(-45deg)}@media (max-width:768px){.sb-header__nav-toggle{display:inline-flex}.sb-header__nav{position:absolute;inset-inline:0;top:100%;background:rgba(248,250,252,0.98);border-bottom:1px solid var(--color-border);box-shadow:0 20px 40px rgba(15,23,42,0.12);transform-origin:top center;transform:scaleY(0.9);opacity:0;visibility:hidden;pointer-events:none;transition:opacity var(--transition-base),transform var(--transition-base),visibility var(--transition-base)}.sb-header__nav-list{flex-direction:column;align-items:flex-start;padding:0.75rem 1.25rem 1rem;gap:0.25rem}.sb-header__nav-link{width:100%;justify-content:flex-start}.sb-header__nav--open{opacity:1;visibility:visible;pointer-events:auto;transform:scaleY(1)}}@media (prefers-reduced-motion:reduce){.sb-header__nav,.sb-header__nav-toggle-bar{transition:none}