/* ── Navigation ── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  transition: background var(--transition-base), backdrop-filter var(--transition-base), box-shadow var(--transition-base);
}

.nav.scrolled {
  background: rgba(17, 17, 17, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: 0 1px 0 var(--color-border);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.nav__logo {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.nav__logo img {
  height: 48px;
  width: auto;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.nav__links a {
  font-size: var(--text-sm);
  font-weight: 500;
  color: rgba(255, 255, 255, 0.8);
  transition: color var(--transition-fast);
  position: relative;
}

.nav__links a::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 0;
  width: 0;
  height: 1.5px;
  background: var(--color-accent);
  transition: width var(--transition-base);
}

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

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

.nav__cta {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

/* Hamburger */
.nav__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-2);
  cursor: pointer;
}

.nav__hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all var(--transition-base);
}

.nav__hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav__hamburger.open span:nth-child(2) {
  opacity: 0;
}
.nav__hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile menu */
.nav__mobile {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  background: rgba(17, 17, 17, 0.97);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  padding: var(--space-8) var(--space-6);
  flex-direction: column;
  gap: var(--space-6);
  border-top: 1px solid var(--color-border);
  z-index: 99;
}

.nav__mobile.open {
  display: flex;
}

.nav__mobile a {
  font-size: var(--text-xl);
  font-weight: 600;
  color: var(--color-text);
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-border);
  transition: color var(--transition-fast);
}

.nav__mobile a:hover {
  color: var(--color-accent);
}

.nav__mobile .btn {
  width: 100%;
  justify-content: center;
  margin-top: var(--space-2);
}

/* ── Footer ── */
.footer {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding: var(--space-16) 0 var(--space-8);
}

.footer__top {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: var(--space-12);
  padding-bottom: var(--space-12);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--space-8);
}

.footer__brand .footer__logo {
  height: 48px;
  margin-bottom: var(--space-4);
}

.footer__tagline {
  font-size: var(--text-sm);
  color: var(--color-muted);
  max-width: 220px;
}

.footer__heading {
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: var(--space-4);
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer__links a {
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.6);
  transition: color var(--transition-fast);
}

.footer__links a:hover {
  color: var(--color-accent);
}

.footer__contact p {
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.6);
  margin-bottom: var(--space-1);
}

.footer__contact a {
  font-size: var(--text-sm);
  color: var(--color-accent);
}

.footer__socials {
  display: flex;
  gap: var(--space-4);
  margin-top: var(--space-5);
}

.footer__socials a {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-muted);
  font-size: var(--text-sm);
  transition: all var(--transition-fast);
}

.footer__socials a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: var(--text-xs);
  color: var(--color-muted);
}

/* ── Nav responsive ── */
@media (max-width: 768px) {
  .nav__links,
  .nav__cta {
    display: none;
  }

  .nav__hamburger {
    display: flex;
  }

  .footer__top {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }

  .footer__bottom {
    flex-direction: column;
    gap: var(--space-2);
    text-align: center;
  }
}

/* ── Back to Top ── */
.back-to-top {
  position: fixed;
  bottom: var(--space-8);
  right: var(--space-8);
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-accent);
  color: #111111;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border: none;
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity 0.3s ease, transform 0.3s ease;
  z-index: 50;
}

.back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--color-accent-dark);
}