.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 0 24px;
  transition: background var(--t-lg) var(--ease), border-color var(--t-lg) var(--ease);
  border-bottom: 1px solid transparent;
}

.header.scrolled {
  background: rgba(10, 10, 12, 0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom-color: var(--border);
}

.nav {
  max-width: 1200px;
  margin: 0 auto;
  height: 64px;
  display: flex;
  align-items: center;
  gap: 40px;
}

.nav-logo {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-1);
  display: flex;
  align-items: center;
  gap: 2px;
  flex-shrink: 0;
}

.logo-icon {
  color: var(--accent);
  font-weight: 400;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 8px;
  margin-left: auto;
}

.nav-links a {
  font-size: 0.9rem;
  color: var(--text-2);
  padding: 6px 14px;
  border-radius: var(--r-sm);
  transition: color var(--t) var(--ease), background var(--t) var(--ease);
}

.nav-links a:hover {
  color: var(--text-1);
  background: var(--bg-elevated);
}

.nav-github {
  display: flex;
  align-items: center;
  gap: 6px;
}

.btn-download-sm {
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 500;
  background: var(--accent);
  color: #fff;
  padding: 8px 20px;
  border-radius: var(--r-sm);
  transition: background var(--t) var(--ease), box-shadow var(--t) var(--ease);
  flex-shrink: 0;
}

.btn-download-sm:hover {
  background: #ea6a0d;
  box-shadow: 0 0 20px var(--accent-glow);
}

.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  margin-left: auto;
}

.nav-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-2);
  border-radius: 1px;
  transition: transform var(--t) var(--ease), opacity var(--t) var(--ease);
}

@media (max-width: 768px) {
  .nav-links, .btn-download-sm { display: none; }
  .nav-hamburger { display: flex; }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(10, 10, 12, 0.96);
    backdrop-filter: blur(20px);
    padding: 16px;
    border-bottom: 1px solid var(--border);
    gap: 4px;
  }

  .nav-links.open a {
    padding: 12px 16px;
    font-size: 1rem;
  }
}