.header { background-color: #ffffff; padding: 12px 0; position: sticky; top: 0; z-index: 100; transition: box-shadow 0.3s ease; border-bottom: 1px solid rgba(0, 0, 0, 0.08); }
.header.scrolled { box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08); }
.header .header-inner { display: flex; align-items: center; justify-content: space-between; }
.header .header-logo { display: flex; align-items: center; }
.header .header-logo .header-logo-img { height: 36px; width: auto; display: block; }
.header .nav { display: none; }
.header .nav.active { display: block; position: absolute; top: 100%; left: 0; right: 0; background-color: #ffffff; padding: 16px 20px; border-top: 1px solid rgba(0, 0, 0, 0.08); box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06); }
.header .nav-list { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 0; }
.header .nav-item { position: relative; }
.header .nav-link { display: block; padding: 10px 0; color: #555555; font-size: 14px; font-weight: 500; transition: color 0.2s ease; }
.header .nav-link:hover { color: #2563eb; }
.header .nav-dropdown { position: relative; }
.header .nav-dropdown .nav-link { display: flex; align-items: center; gap: 6px; }
.header .dropdown-menu { display: none; list-style: none; padding: 0; margin: 0; padding-left: 16px; }
.header .nav-dropdown.open .dropdown-menu { display: block; }
.header .dropdown-menu .dropdown-link { display: block; padding: 8px 0; color: #777777; font-size: 13px; transition: color 0.2s ease; }
.header .dropdown-menu .dropdown-link:hover { color: #2563eb; }
.header .hamburger { display: flex; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 8px; }
.header .hamburger .hamburger-line { width: 24px; height: 2px; background-color: #333333; transition: all 0.3s ease; border-radius: 2px; }
.header .hamburger.active .hamburger-line:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.header .hamburger.active .hamburger-line:nth-child(2) { opacity: 0; }
.header .hamburger.active .hamburger-line:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }
@media (min-width: 768px) {
  .header .header-logo .header-logo-img { height: 42px; }
}
@media (min-width: 1024px) {
  .header .nav { display: block; }
  .header .nav-list { flex-direction: row; align-items: center; gap: 4px; }
  .header .nav-link { padding: 8px 12px; font-size: 13px; }
  .header .hamburger { display: none; }
  .header .nav-dropdown .dropdown-menu { display: none; position: absolute; top: 100%; left: 0; background-color: #ffffff; border: 1px solid rgba(0, 0, 0, 0.10); border-radius: 6px; padding: 8px 0; min-width: 180px; box-shadow: 0 8px 24px rgba(0, 0, 0, 0.10); }
  .header .nav-dropdown.open .dropdown-menu { display: block; }
  .header .dropdown-menu .dropdown-link { padding: 8px 16px; }
  .header .dropdown-menu { padding-left: 0; }
}