/* ═══════════════════════════════════════
   STICKY HEADER / NAVIGATION
   ═══════════════════════════════════════ */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: all var(--transition-base);
  background: transparent;
}

.site-header.scrolled {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: var(--shadow-sm);
  padding: 12px 0;
}

.header-inner {
  max-width: var(--container-wide);
  margin: 0 auto;
  padding: 0 var(--space-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* ── Logo ── */
.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.logo__icon {
  width: 38px;
  height: 38px;
}

.logo__text {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 3px;
  color: var(--color-slate-200);
  transition: color var(--transition-base);
}

.site-header.scrolled .logo__text {
  color: var(--color-navy-800);
}

/* ── Nav ── */
.nav {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
}

.nav__links {
  display: flex;
  gap: var(--space-lg);
  list-style: none;
}

.nav__link {
  font-size: 0.9rem;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.8);
  transition: color var(--transition-fast);
  position: relative;
}

.nav__link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-accent);
  transition: width var(--transition-base);
}

.nav__link:hover,
.nav__link[aria-current="page"] {
  color: var(--color-white);
}

.nav__link:hover::after,
.nav__link[aria-current="page"]::after {
  width: 100%;
}

.site-header.scrolled .nav__link {
  color: var(--color-slate-600);
}

.site-header.scrolled .nav__link:hover,
.site-header.scrolled .nav__link[aria-current="page"] {
  color: var(--color-brand-blue);
}

.nav__cta {
  display: flex;
  gap: var(--space-md);
  align-items: center;
}

/* ── Mobile Hamburger ── */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.hamburger__line {
  width: 24px;
  height: 2px;
  background: var(--color-white);
  border-radius: 2px;
  transition: all var(--transition-base);
}

.site-header.scrolled .hamburger__line {
  background: var(--color-navy-800);
}

.hamburger.open .hamburger__line:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.open .hamburger__line:nth-child(2) {
  opacity: 0;
}

.hamburger.open .hamburger__line:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ── Mobile Nav Overlay ── */
.mobile-nav {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-navy-900);
  z-index: 999;
  padding: 100px var(--space-xl) var(--space-xl);
  flex-direction: column;
  gap: var(--space-lg);
}

.mobile-nav.open {
  display: flex;
}

.mobile-nav__link {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--color-white);
  padding: var(--space-md) 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.mobile-nav__cta {
  margin-top: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}