/* ============================================================
   LAYOUT.CSS — Nav, Container, Sections, Footer
   ============================================================ */

/* ── Navigation ── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: var(--z-nav);
  display: flex;
  align-items: center;
  transition: background var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
  border-bottom: 1px solid transparent;
}

.nav.scrolled {
  background: rgba(10, 13, 20, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom-color: var(--clr-border);
  box-shadow: 0 4px 24px rgba(0,0,0,0.4);
}

.nav__inner {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--sp-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-8);
}

.nav__logo {
  font-size: var(--fs-xl);
  font-weight: var(--fw-extrabold);
  letter-spacing: var(--ls-tight);
  background: linear-gradient(135deg, var(--clr-blue), var(--clr-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  flex-shrink: 0;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
}

.nav__link {
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  color: var(--clr-text-secondary);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--radius-md);
  transition: color var(--transition-fast), background var(--transition-fast);
  position: relative;
}

.nav__link::after {
  content: '';
  position: absolute;
  bottom: 4px;
  left: 50%;
  transform: translateX(-50%) scaleX(0);
  width: 16px;
  height: 2px;
  background: var(--clr-blue);
  border-radius: var(--radius-full);
  transition: transform var(--transition-base);
}

.nav__link:hover,
.nav__link.active {
  color: var(--clr-text-primary);
  background: rgba(59,130,246,0.08);
}

.nav__link.active::after {
  transform: translateX(-50%) scaleX(1);
}

.nav__cta {
  font-size: var(--fs-sm);
  font-weight: var(--fw-semibold);
  color: var(--clr-blue);
  padding: var(--sp-2) var(--sp-4);
  border: 1px solid var(--clr-blue);
  border-radius: var(--radius-md);
  transition: background var(--transition-fast), color var(--transition-fast), box-shadow var(--transition-fast);
  flex-shrink: 0;
}

.nav__cta:hover {
  background: var(--clr-blue);
  color: #fff;
  box-shadow: var(--shadow-glow-blue);
}

.nav__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--sp-2);
  border-radius: var(--radius-md);
  transition: background var(--transition-fast);
}

.nav__hamburger:hover {
  background: rgba(255,255,255,0.05);
}

.nav__hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--clr-text-primary);
  border-radius: var(--radius-full);
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.nav__hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav__hamburger.open span:nth-child(2) {
  opacity: 0;
  transform: scaleX(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(10,13,20,0.97);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--clr-border);
  padding: var(--sp-4) var(--sp-6) var(--sp-6);
  z-index: calc(var(--z-nav) - 1);
  flex-direction: column;
  gap: var(--sp-1);
  transform: translateY(-8px);
  opacity: 0;
  pointer-events: none;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.nav__mobile.open {
  display: flex;
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.nav__mobile .nav__link {
  padding: var(--sp-3) var(--sp-4);
  font-size: var(--fs-base);
}

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

/* ── Section base ── */
section {
  padding: var(--section-py) 0;
  position: relative;
}

section:nth-child(even) {
  background: var(--clr-bg-secondary);
}

/* ── Footer ── */
.footer {
  background: var(--clr-bg-secondary);
  border-top: 1px solid var(--clr-border);
  padding: var(--sp-12) 0 var(--sp-8);
}

.footer__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-6);
  text-align: center;
}

.footer__logo {
  font-size: var(--fs-2xl);
  font-weight: var(--fw-extrabold);
  background: linear-gradient(135deg, var(--clr-blue), var(--clr-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer__tagline {
  font-size: var(--fs-sm);
  color: var(--clr-text-muted);
}

.footer__links {
  display: flex;
  gap: var(--sp-6);
  flex-wrap: wrap;
  justify-content: center;
}

.footer__links a {
  font-size: var(--fs-sm);
  color: var(--clr-text-secondary);
  transition: color var(--transition-fast);
}

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

.footer__divider {
  width: 100%;
  height: 1px;
  background: var(--clr-border);
}

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