/* ============================================================
   NAVIGATION
   ============================================================ */

nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: var(--nav-h);
  padding: 0 4rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(3, 3, 8, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  transition: background .4s var(--ease);
}

nav.scrolled {
  background: rgba(3, 3, 8, 0.95);
}

/* Active section “station” */
.nav-links a.active {
  color: var(--cyan);
}

.nav-links a.active::after {
  width: 100%;
}


/* Logo */
.nav-logo {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.1rem;
  letter-spacing: .15em;
  color: var(--cyan);
  text-decoration: none;
}
.nav-logo span { color: var(--white); }

/* Links */
.nav-links {
  display: flex;
  gap: 2.5rem;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: var(--grey);
  font-size: .85rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  transition: color .3s;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px; left: 0;
  width: 0; height: 1px;
  background: var(--cyan);
  transition: width .3s;
}

.nav-links a:hover            { color: var(--cyan); }
.nav-links a:hover::after     { width: 100%; }

/* CTA button */
.nav-cta {
  padding: .5rem 1.5rem !important;
  border: 1px solid var(--cyan) !important;
  color: var(--cyan) !important;
  border-radius: 2px;
}
.nav-cta::after { display: none !important; }
.nav-cta:hover {
  background: var(--cyan) !important;
  color: var(--black) !important;
}

/* Mobile hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: none;
  padding: .5rem;
}
.nav-toggle span {
  display: block;
  width: 24px; height: 1px;
  background: var(--white);
  transition: all .3s;
}

/* Responsive */
@media (max-width: 1024px) {
  nav { padding: 0 2rem; }

  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-h); left: 0; right: 0;
    flex-direction: column;
    gap: 0;
    background: rgba(3, 3, 8, 0.97);
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
    max-height: calc(100vh - var(--nav-h));
    overflow-y: auto;
    z-index: 99;
  }
  .nav-links.open  { display: flex; }
  .nav-links li    { width: 100%; }
  .nav-links a     { display: block; padding: 1rem 2rem; }

  .nav-toggle { display: flex; cursor: pointer; }

  .nav-links a { font-size: .95rem; }
  .nav-links a { padding: 1rem 1.25rem; }
}

@media (max-width: 640px) {
  nav { padding: 0 0.85rem; }
  .nav-links a { padding: .8rem 0.95rem; font-size: .88rem; }
  .nav-toggle { gap: 4px; }
  .nav-toggle span { width: 18px; }
}