/* Header – Produkt-Telefon */

.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-height);
  z-index: var(--z-header);
  background-color: rgba(255,255,255,0.9);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}
.header.is-scrolled { border-bottom-color: var(--color-border); box-shadow: var(--shadow-sm); }

.header__inner {
  display: flex;
  align-items: center;
  height: 100%;
  gap: var(--space-8);
}

.header__logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  flex-shrink: 0;
}

.header__nav { flex: 1; }

.nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-6);
}

.nav__link {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
}
.nav__link:hover, .nav__link.is-active { color: var(--color-text); }

.header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-left: auto;
}

.mobile-menu-btn { display: none; padding: var(--space-2); }
.hamburger { display: flex; flex-direction: column; gap: 5px; width: 22px; }
.hamburger span { display: block; height: 2px; border-radius: 2px; background-color: var(--color-text); transition: transform var(--transition-base), opacity var(--transition-base); }
.mobile-menu-btn[aria-expanded="true"] .hamburger span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.mobile-menu-btn[aria-expanded="true"] .hamburger span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.mobile-menu-btn[aria-expanded="true"] .hamburger span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-menu {
  background: #fff;
  padding: 0 var(--container-padding);
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow), padding var(--transition-slow);
  border-bottom: 1px solid var(--color-border);
}
.mobile-menu[aria-hidden="false"] { max-height: 400px; padding-bottom: var(--space-6); }

.mobile-menu__list { display: flex; flex-direction: column; gap: var(--space-1); padding-top: var(--space-4); }
.mobile-menu__link {
  display: block; padding: var(--space-3) 0;
  font-size: var(--font-size-base); font-weight: var(--font-weight-medium);
  color: var(--color-text-muted); border-bottom: 1px solid var(--color-border);
  transition: color var(--transition-fast);
}
.mobile-menu__link:hover { color: var(--color-text); }

@media (max-width: 768px) {
  .header__nav { display: none; }
  .header__actions .btn { display: none; }
  .mobile-menu-btn { display: flex; }
}