.site-header {
  position: fixed;
  z-index: 1000;
  top: 0;
  left: 0;
  width: 100%;
  padding: 20px 0;
  border-bottom: 0;
  background: transparent;
  transition: background var(--transition), padding var(--transition), box-shadow var(--transition);
}

.nav-inner {
  display: flex;
  min-height: 72px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 0 22px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 999px;
  background: rgba(7, 23, 27, 0.18);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background var(--transition), border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.site-header.scrolled { padding: 12px 0; }

.site-header.scrolled .nav-inner {
  border-color: rgba(255, 255, 255, 0.1);
  background: rgba(7, 23, 27, 0.5);
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.22);
}

.site-brand {
  display: inline-flex;
  flex-shrink: 0;
  align-items: center;
  gap: 14px;
}

.site-brand img {
  display: block;
  width: auto;
  height: 100px;
  object-fit: contain;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 28px;
  margin-left: auto;
}

.site-nav a {
  position: relative;
  color: var(--text-soft);
  font-size: 0.96rem;
  font-weight: 500;
  transition: color var(--transition), opacity var(--transition);
}

.site-nav a:hover { color: var(--text); }

.site-nav a::after {
  content: "";
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 100%;
  height: 2px;
  border-radius: 999px;
  background: var(--primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}

.site-nav a:hover::after { transform: scaleX(1); }

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

@media (max-width: 900px) {
  .site-nav,
  .brand-subtitle { display: none; }
}

@media (max-width: 640px) {
  .container { padding-inline: 12px; }
  .site-header { padding: 10px 0; }
  .nav-inner {
    min-height: 60px;
    justify-content: space-between;
    gap: 10px;
    padding-inline: 12px;
  }
  .site-brand img { height: 38px; }
}

@media (max-width: 600px) {
  .site-brand img {
    width: 150px;
    max-width: 46vw;
  }

  .nav-actions .btn-primary {
    padding-inline: 16px;
    font-size: 0.8rem;
    box-shadow: 0 6px 18px rgba(16, 183, 201, 0.25), inset 0 2px 1px rgba(255, 255, 255, 0.35);
  }
}