/* ============================================================
   Levitass AI — Layout (Navigation, Footer, Grid)
   ============================================================ */

/* ── Container ── */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.container--sm {
  max-width: var(--container-sm);
}

/* ── Section ── */
.section {
  padding: var(--section-padding) 0;
  position: relative;
  overflow: hidden;
}

.section--alt {
  background-color: var(--color-bg-secondary);
}

/* Mesh gradient backgrounds for sections */
.section--alt::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background:
    radial-gradient(ellipse 80% 50% at 20% 40%, rgba(124, 107, 255, 0.06) 0%, transparent 50%),
    radial-gradient(ellipse 60% 40% at 80% 60%, rgba(6, 182, 212, 0.04) 0%, transparent 50%);
  pointer-events: none;
}

.section__header {
  text-align: center;
  margin-bottom: var(--space-16);
}

.section__title {
  margin-bottom: var(--space-4);
}

.section__subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* ── Navigation ── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: var(--z-nav);
  transition: background-color var(--transition-base), box-shadow var(--transition-base);
}

.nav--scrolled {
  background-color: rgba(5, 5, 16, 0.9);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  box-shadow: 0 1px 0 var(--color-border), var(--shadow-glow);
}

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

.nav__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-family-en);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  text-decoration: none;
  letter-spacing: var(--letter-spacing-tight);
}

.nav__logo-icon {
  width: 36px;
  height: 36px;
  object-fit: contain;
  border-radius: var(--radius-sm);
}

.nav__logo span {
  background: var(--color-accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

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

.nav__link {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
  position: relative;
}

.nav__link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent-gradient);
  transition: width var(--transition-base);
  border-radius: var(--radius-full);
}

.nav__link:hover,
.nav__link--active {
  color: var(--color-text-primary);
}

.nav__link:hover::after,
.nav__link--active::after {
  width: 100%;
}

.nav__cta {
  margin-left: var(--space-4);
}

/* Mobile Menu Toggle */
.nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 28px;
  height: 28px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
  z-index: calc(var(--z-nav) + 1);
}

.nav__toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-text-primary);
  border-radius: var(--radius-full);
  transition: transform var(--transition-base), opacity var(--transition-fast);
}

.nav__toggle--open .nav__toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav__toggle--open .nav__toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav__toggle--open .nav__toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

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

.footer::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--color-accent-gradient);
  opacity: 0.3;
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-10);
  margin-bottom: var(--space-12);
}

.footer__brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.footer__logo {
  font-family: var(--font-family-en);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  text-decoration: none;
}

.footer__logo span {
  background: var(--color-accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer__desc {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: var(--line-height-relaxed);
}

.footer__heading {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  text-transform: uppercase;
  letter-spacing: var(--letter-spacing-wide);
  margin-bottom: var(--space-5);
}

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

.footer__link {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer__link:hover {
  color: var(--color-text-primary);
}

.footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-border);
}

.footer__copy {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

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

.footer__social {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  color: var(--color-text-muted);
  transition: all var(--transition-base);
}

.footer__social:hover {
  background: var(--color-accent-gradient);
  color: white;
  border-color: transparent;
  transform: translateY(-2px);
}

/* ── Grid Utilities ── */
.grid {
  display: grid;
  gap: var(--space-8);
}

.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

/* ── Responsive ── */
@media (max-width: 1024px) {
  .grid--4 { grid-template-columns: repeat(2, 1fr); }  
  .footer__grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .container { padding: 0 var(--space-4); }
  
  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: 1fr; }

  /* Mobile Navigation */
  .nav__links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 320px;
    height: 100vh;
    background-color: var(--color-bg-secondary);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: var(--space-8);
    transition: right var(--transition-slow);
    border-left: 1px solid var(--color-border);
  }

  .nav__links--open {
    right: 0;
  }

  .nav__toggle {
    display: flex;
  }

  .nav__cta {
    margin-left: 0;
  }

  /* Footer Mobile */
  .footer__grid { grid-template-columns: 1fr; }
  .footer__bottom { flex-direction: column; gap: var(--space-4); text-align: center; }
}

/* ── Mobile Overlay ── */
.nav-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  z-index: calc(var(--z-nav) - 1);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-base), visibility var(--transition-base);
}

.nav-overlay--visible {
  opacity: 1;
  visibility: visible;
}

/* ── Page offset for fixed nav ── */
.page-content {
  margin-top: var(--nav-height);
}