#header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-height);
  background: rgba(10, 0, 0, 0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: var(--transition);
  width: 100%;
  overflow-x: hidden;
  overflow-y: visible;
  box-sizing: border-box;
}

#header.scrolled {
  background: rgba(10, 0, 0, 0.98);
  border-bottom-color: rgba(245, 197, 24, 0.25);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
}

.header-container {
  max-width: var(--container-max);
  width: 100%;
  margin: 0 auto;
  padding: 0 var(--container-pad);
  height: 100%;
  display: flex;
  align-items: center;
  gap: 2rem;
  box-sizing: border-box;
  overflow: hidden;
}

.logo-link {
  flex-shrink: 0;
  display: flex;
  align-items: center;
}

.logo-link:hover .logo {
  filter: drop-shadow(0 0 8px rgba(245, 197, 24, 0.6));
}

.logo {
  height: 42px;
  width: auto;
  transition: filter 0.3s ease;
}

#main-nav {
  flex: 1;
  display: flex;
  justify-content: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-link {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.04em;
  color: var(--color-muted);
  padding: 0.5rem 1rem;
  border-radius: var(--border-radius);
  transition: var(--transition);
  position: relative;
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-gold);
  background: rgba(245, 197, 24, 0.08);
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 50%;
  transform: translateX(-50%);
  width: 20px;
  height: 2px;
  background: var(--color-gold);
  border-radius: 1px;
}

.btn-download {
  flex-shrink: 0;
  padding: 0.6rem 1.4rem;
  font-size: 0.9rem;
}

.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  gap: 5px;
  flex-shrink: 0;
  margin-left: auto;
  border-radius: var(--border-radius);
  transition: var(--transition);
}

.hamburger:hover {
  background: rgba(245, 197, 24, 0.1);
}

.hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-gold);
  border-radius: 1px;
  transition: var(--transition);
  transform-origin: center;
}

.hamburger[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.hamburger[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.hamburger[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.mobile-nav-overlay {
  display: none;
  position: fixed;
  inset: var(--header-height) 0 0 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 999;
  backdrop-filter: blur(4px);
  animation: fadeIn 0.2s ease;
}

.mobile-nav-overlay.open {
  display: block;
}

@media (max-width: 1024px) {
  .hamburger {
    display: flex;
  }

  #main-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    width: 100%;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: 1rem var(--container-pad);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.3s ease, opacity 0.3s ease;
    z-index: 999;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
    box-sizing: border-box;
    overflow-x: hidden;
    overflow-y: auto;
    max-height: calc(100vh - var(--header-height));
  }

  #main-nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .nav-list {
    flex-direction: column;
    gap: 0.25rem;
    width: 100%;
  }

  .nav-link {
    width: 100%;
    padding: 0.9rem 1.25rem;
    font-size: 1.05rem;
    border-radius: var(--border-radius);
  }

  .nav-link.active::after {
    display: none;
  }

  .btn-download {
    display: none;
  }
}