/* ═══════════════════════════════════════════════════════════
   COLAB — nav.css
   Sticky nav · Desktop links · Mobile overlay
   ═══════════════════════════════════════════════════════════ */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: 64px;
  background: rgba(10, 7, 5, 0.80);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(249,115,22,0.08);
  transition: background var(--t-base) var(--ease-out), border-color var(--t-base) var(--ease-out);
}

.nav.scrolled {
  background: rgba(10, 7, 5, 0.96);
  border-bottom-color: rgba(249,115,22,0.16);
}

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

.nav__logo {
  font-family: 'Syne', sans-serif;
  font-weight: 800;
  font-size: 1.2rem;
  color: var(--white);
  letter-spacing: -0.02em;
  flex-shrink: 0;
  transition: opacity var(--t-fast);
  display: flex;
  align-items: center;
}

.nav__logo:hover {
  opacity: 0.80;
}

.nav__logo-text .accent, .nav__logo .accent {
  color: var(--orange);
  text-shadow: var(--glow-text);
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  flex: 1;
  justify-content: center;
}

.nav__link {
  font-family: 'DM Mono', monospace;
  font-size: 0.78rem;
  font-weight: 400;
  letter-spacing: 0.05em;
  color: var(--muted);
  transition: color var(--t-fast);
  position: relative;
  padding-bottom: 2px;
}

.nav__link::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--orange);
  box-shadow: 0 0 8px rgba(249,115,22,0.55);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--t-base) var(--ease-out);
}

.nav__link:hover {
  color: var(--white);
}

.nav__link:hover::after, .nav__link.active::after {
  transform: scaleX(1);
}

.nav__link.active {
  color: var(--white);
}

.nav__cta {
  flex-shrink: 0;
  display: inline-flex !important;
  font-size: 0.78rem;
  padding: 0.55rem 1.2rem;
}

.nav__hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 8px;
  border-radius: var(--radius-sm);
  transition: background var(--t-fast);
  flex-shrink: 0;
}

.nav__hamburger:hover {
  background: rgba(249,115,22,0.10);
}

.nav__hamburger span {
  display: block;
  width: 20px;
  height: 1.5px;
  background: var(--muted);
  border-radius: 2px;
  transition: all var(--t-base) var(--ease-out);
  transform-origin: center;
}

.nav__hamburger[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(6.5px) rotate(45deg);
  background: var(--orange);
}

.nav__hamburger[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.nav__hamburger[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-6.5px) rotate(-45deg);
  background: var(--orange);
}

.nav__overlay {
  position: fixed;
  inset: 0;
  z-index: 1001;
  background: rgba(10, 7, 5, 0.98);
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-start;
  padding: var(--space-lg) var(--space-md);
  opacity: 0;
  pointer-events: none;
  transform: translateX(-100%);
  transition: opacity var(--t-slow) var(--ease-out), transform var(--t-slow) var(--ease-out);
}

.nav__overlay.open {
  opacity: 1;
  pointer-events: all;
  transform: translateX(0);
}

.overlay-close {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  font-size: 1.4rem;
  color: var(--muted);
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  transition: color var(--t-fast), text-shadow var(--t-fast), background var(--t-fast);
}

.overlay-close:hover {
  color: var(--orange);
  text-shadow: var(--glow-text);
  background: rgba(249,115,22,0.08);
}

.overlay__links {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  width: 100%;
}

.overlay__link {
  font-family: 'Syne', sans-serif;
  font-size: clamp(1.6rem, 6vw, 2.8rem);
  font-weight: 700;
  color: var(--muted);
  transition: color var(--t-base) var(--ease-out), transform var(--t-base) var(--ease-out);
  display: inline-block;
  padding: 0.2rem 0;
}

.overlay__link:hover {
  color: var(--white);
  transform: translateX(8px);
}

.overlay__link--cta {
  color: var(--orange);
  text-shadow: var(--glow-text);
  margin-top: var(--space-sm);
}

.overlay__link--cta:hover {
  color: #fb923c;
  transform: translateX(8px);
}

@media (max-width: 1024px) {
  .nav__links { display: none; }
  .nav__cta { display: none !important; }
  .nav__hamburger { display: flex; }
}

@media (max-width: 480px) {
  .nav__inner { padding: 0 var(--space-sm); }
}