/* ═══════════════════════════════════════════════════════
   css/nav.css  —  Navigation styles
═══════════════════════════════════════════════════════ */

.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  padding: 1.5rem 0;
  transition: background 0.4s ease, padding 0.4s ease, backdrop-filter 0.4s ease;
}

.navbar.scrolled {
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  padding: 1rem 0;
  border-bottom: 1px solid var(--border);
}

[data-theme="light"] .navbar.scrolled {
  background: rgba(245, 245, 248, 0.88);
  overflow: hidden;
}

/* Animated red accent lines in light mode header */
[data-theme="light"] .navbar.scrolled::before,
[data-theme="light"] .navbar.scrolled::after {
  content: '';
  position: absolute;
  pointer-events: none;
}

/* Sweeping underline bar */
[data-theme="light"] .navbar.scrolled::before {
  bottom: 0; left: 0;
  height: 2px;
  width: 100%;
  background: linear-gradient(
    90deg,
    transparent 0%,
    var(--accent) 30%,
    var(--accent-cyan) 60%,
    transparent 100%
  );
  background-size: 200% 100%;
  animation: navLineSweep 3s ease-in-out infinite;
}

/* Glowing orb that drifts across */
[data-theme="light"] .navbar.scrolled::after {
  top: 50%;
  left: -80px;
  transform: translateY(-50%);
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(233,69,96,0.18) 0%, transparent 70%);
  animation: navOrbDrift 5s ease-in-out infinite;
}

@keyframes navLineSweep {
  0%   { background-position: 100% 0; opacity: 0.5; }
  50%  { background-position:  0% 0; opacity: 1; }
  100% { background-position: 100% 0; opacity: 0.5; }
}

@keyframes navOrbDrift {
  0%   { left: -80px;  opacity: 0; }
  20%  { opacity: 1; }
  80%  { opacity: 0.8; }
  100% { left: calc(100% + 80px); opacity: 0; }
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(var(--container), calc(100% - 3rem));
  margin-inline: auto;
}

/* Logo */
.nav-logo {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  transition: opacity 0.2s;
}

.nav-logo:hover { opacity: 0.75; }

/* Desktop Links */
.nav-links {
  display: flex;
  gap: 2.5rem;
  align-items: center;
}

.nav-link {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  position: relative;
  padding-bottom: 2px;
  transition: color var(--transition);
}

.nav-link::after {
  content: '';
  position: absolute;
  left: 0; bottom: 0;
  height: 1px;
  width: 0%;
  background: var(--accent);
  transition: width 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

.nav-link:hover { color: var(--text); }
.nav-link:hover::after { width: 100%; }

/* Actions */
.nav-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Theme Toggle */
.theme-toggle {
  width: 36px; height: 36px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-muted);
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.theme-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 28px;
  padding: 4px;
}

.hamburger span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

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

/* Mobile Overlay */
.mobile-menu {
  position: fixed;
  inset: 0;
  background: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.35s ease;
  z-index: 999;
}

.mobile-menu.open {
  opacity: 1;
  pointer-events: all;
}

.mobile-links {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  text-align: center;
}

.mobile-link {
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 6vw, 2.5rem);
  font-weight: 700;
  color: var(--text-muted);
  transition: color var(--transition);
}

.mobile-link:hover { color: var(--accent); }