.header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid var(--border);
  background: rgba(9, 9, 11, 0.85);
  backdrop-filter: blur(12px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
}

.logo {
  font-family: var(--display);
  font-size: 1.2rem;
  font-weight: 600;
  text-decoration: none;
  color: var(--text);
  letter-spacing: -0.02em;
}

.logo::after {
  content: ".";
  color: var(--blue);
}

.nav {
  display: flex;
  gap: 2rem;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 200ms;
  position: relative;
}

.nav a::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1.5px;
  background: var(--blue);
  transition: width 250ms;
}

.nav a:hover {
  color: var(--text);
}

.nav a:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  width: 2.5rem;
  height: 2.5rem;
  cursor: pointer;
  color: var(--text);
  padding: 0.5rem;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 4px;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 1.5px;
  background: currentColor;
  border-radius: 1px;
}