/* ── header ───────────────────────────────────────────────────────── */
header {
  position: relative; z-index: 100;
  padding: 1.5rem 5%;
  background: linear-gradient(180deg, rgba(10, 10, 15, 0.95) 0%, rgba(10, 10, 15, 0.7) 100%);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
  border-image: linear-gradient(90deg, transparent, var(--accent-red), var(--accent-gold), transparent) 1;
}
.logo {
  font-family: 'Orbitron', monospace;
  font-size: 3rem; font-weight: 900;
  background: linear-gradient(120deg, var(--accent-red) 0%, var(--accent-gold) 50%, var(--accent-silver) 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
  letter-spacing: 0.15em;
  filter: drop-shadow(0 0 30px rgba(230, 57, 70, 0.6));
  text-align: center;
}
.tagline {
  font-size: 0.8rem; color: var(--accent-silver);
  letter-spacing: 0.4em; margin-top: 0.3rem;
  text-transform: uppercase; opacity: 0.8; text-align: center;
}