/* ============================================
   NAV.CSS — Sticky Navigation Bar
   ============================================ */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--nav-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  transition: transform var(--transition-base);
}

.nav--hidden {
  transform: translateY(-100%);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.nav__logo {
  font-size: var(--text-xl);
  font-weight: var(--font-bold);
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.nav__logo span {
  color: var(--accent);
}

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

.nav__link {
  position: relative;
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  padding: var(--space-xs) 0;
  transition: color var(--transition-fast);
}

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

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

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

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

/* --- Controls (theme + language toggles) --- */
.nav__controls {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.nav__toggle-btn {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  transition: all var(--transition-fast);
  font-size: var(--text-lg);
}

.nav__toggle-btn:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-soft);
}

.nav__lang-btn {
  font-size: var(--text-xs);
  font-weight: var(--font-bold);
  letter-spacing: 0.5px;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  transition: all var(--transition-fast);
}

.nav__lang-btn:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-soft);
}

/* --- Mobile Hamburger --- */
.nav__hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  cursor: pointer;
  z-index: 1001;
}

.nav__hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: var(--radius-full);
  transition: all var(--transition-base);
  margin: 0 auto;
}

.nav__hamburger--active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav__hamburger--active span:nth-child(2) {
  opacity: 0;
}

.nav__hamburger--active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* --- Mobile Menu --- */
@media (max-width: 768px) {
  .nav__hamburger {
    display: flex;
  }

  .nav__links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 75%;
    max-width: 320px;
    height: 100vh;
    background: var(--bg-secondary);
    flex-direction: column;
    justify-content: center;
    gap: var(--space-xl);
    padding: var(--space-2xl);
    transition: right var(--transition-base);
    box-shadow: var(--shadow-xl);
  }

  .nav__links--open {
    right: 0;
  }

  .nav__link {
    font-size: var(--text-lg);
  }

  .nav__controls {
    position: absolute;
    bottom: var(--space-2xl);
    left: 50%;
    transform: translateX(-50%);
  }

  .nav__overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
  }

  .nav__overlay--visible {
    display: block;
  }
}