/* ==========================================================================
   Navigation
   ========================================================================== */
#main-nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background-color: transparent;
  transition: background-color var(--duration-normal) var(--ease-out),
              box-shadow var(--duration-normal) var(--ease-out);
}

#main-nav.nav-solid {
  background-color: var(--color-nav-solid);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-lg);
  height: var(--nav-height);
}

.nav-logo {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-white);
  text-decoration: none;
  letter-spacing: 0.05em;
  display: flex;
  align-items: center;
}

.nav-logo-img {
  height: 40px;
  width: 40px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid rgba(255, 255, 255, 0.5);
}

.nav-logo:hover {
  color: var(--color-white);
  opacity: 0.85;
}

.nav-links {
  display: flex;
  gap: var(--space-md);
  align-items: center;
}

.nav-links a {
  color: var(--color-white);
  text-decoration: none;
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  padding: var(--space-xs) 0;
  position: relative;
  transition: opacity var(--duration-fast) var(--ease-out);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-white);
  transition: width var(--duration-normal) var(--ease-out);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-links a.active {
  opacity: 1;
}

/* Hamburger toggle — hidden on desktop */
.hamburger-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  padding: 6px;
}

.hamburger-bar {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-white);
  border-radius: 2px;
  transition: transform var(--duration-fast) var(--ease-out),
              opacity var(--duration-fast) var(--ease-out);
}

/* Hamburger → X Animation */
#main-nav.menu-open .hamburger-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

#main-nav.menu-open .hamburger-bar:nth-child(2) {
  opacity: 0;
}

#main-nav.menu-open .hamburger-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

#main-nav.menu-open {
  background-color: var(--color-nav-solid);
}