#main-nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: var(--color-bg);
  z-index: 100;
  padding-top: var(--space-2);
  padding-bottom: var(--space-2);
}

#main-nav.nav-scrolled {
  border-bottom: 1px solid var(--color-border);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 100%;
  padding: 0 var(--nav-pad-x);
  max-width: 100%;
}

.nav-logo {
  font-size: var(--text-4xl);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: var(--nav-gap);
  align-items: center;
}

.nav-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  width: 46px;
  text-decoration: none;
  color: var(--color-text-muted);
  transition: var(--transition);
}

.nav-icon {
  width: var(--nav-icon-size);
  height: var(--nav-icon-size);
  display: flex;
  align-items: center;
  justify-content: center;
}

.nav-icon svg {
  width: var(--nav-icon-size);
  height: var(--nav-icon-size);
  display: block;
}

.nav-label {
  font-size: var(--text-xs);
  font-weight: var(--font-weight-medium);
}

.nav-btn:hover,
.nav-btn:focus-visible {
  color: var(--color-accent);
}

/* Scroll-spy sets .active; stroke uses currentColor on inner svg. */
#main-nav .nav-links > .nav-btn.active,
#main-nav .nav-links > .nav-btn.active .nav-label {
  color: var(--color-accent);
}

#main-nav .nav-links > .nav-btn.active .nav-icon svg,
#main-nav .nav-links > .nav-btn.active .nav-icon svg path,
#main-nav .nav-links > .nav-btn.active .nav-icon svg circle {
  color: var(--color-accent);
  stroke: var(--color-accent);
}

.nav-hamburger {
  display: none;
  align-items: center;
  justify-content: center;
  padding: var(--space-2);
  background: transparent;
  border: none;
  cursor: pointer;
  color: var(--color-text-primary);
}

.nav-hamburger svg {
  width: var(--nav-icon-size);
  height: var(--nav-icon-size);
  display: block;
}