.app-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header, 50);
  background: var(--color-header-bg, rgba(255, 255, 255, 0.9));
  backdrop-filter: var(--blur-header, blur(12px));
  border-bottom: 1px solid var(--color-border-soft, #cbd5e1);
}

.app-header a {
  color: var(--color-text-main, #0f172a);
  text-decoration: none;
  font-size: var(--fs-small, 0.9rem);
  font-weight: var(--fw-semibold, 600);
  padding: 10px 12px;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: background 160ms ease, transform 160ms ease;
}

.app-header a.nav-app {
  background: var(--cta-primary-bg, #005ac1);
  color: var(--cta-primary-text, #ffffff);
  padding: 10px 18px;
}

.app-header a.nav-app:hover {
  background: var(--cta-primary-bg-hover, #0047a0);
}

.app-header a:hover {
  background: var(--color-hover-soft, rgba(15, 23, 42, 0.05));
}

.app-header a:active {
  transform: translateY(1px);
}

.app-header a:focus-visible {
  outline: 2px solid var(--color-focus-ring, rgba(0, 90, 193, 0.35));
  outline-offset: 2px;
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  gap: var(--space-sm, 8px);
  font-weight: var(--fw-semibold, 600);
}

.brand-icon {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-full, 9999px);
  background: var(--color-accent, #005ac1);
  color: var(--color-on-accent, #ffffff);
  display: flex;
  align-items: center;
  justify-content: center;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: var(--space-md, 16px);
}

.nav-overflow {
  position: relative;
  display: none;
}

.nav-toggle {
  background: none;
  border: 1px solid var(--color-border-soft, #cbd5e1);
  border-radius: var(--radius-full, 9999px);
  padding: 8px 14px;
  font-size: var(--fs-small, 0.9rem);
  font-weight: var(--fw-semibold, 600);
  cursor: pointer;
}

.nav-menu {
  position: absolute;
  top: 110%;
  right: 0;
  background: var(--color-bg-surface, #ffffff);
  border: 1px solid var(--color-border-soft, #cbd5e1);
  border-radius: var(--radius-md, 16px);
  box-shadow: var(--shadow-card, 0 12px 32px -16px rgba(0, 0, 0, 0.24));
  min-width: 160px;
  display: none;
  flex-direction: column;
  z-index: var(--z-header, 50);
}

.nav-menu a {
  padding: 10px 14px;
  white-space: nowrap;
}

@media (max-width: 520px) {
  .header-nav > a {
    display: none;
  }
  .nav-overflow {
    display: block;
  }
}

@media (max-width: 768px) {
  .header-container {
    justify-content: space-between;
  }

  .header-nav {
    gap: var(--space-sm, 8px);
  }

  .header-nav a {
    font-size: 0.85rem;
    padding: 8px 10px;
  }

  .header-nav a.nav-app {
    padding: 8px 14px;
  }
}