Menú Desplegable Multinivel

.multi-dropdown-demo {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 380px;
  border-radius: 16px;
  padding: 30px;
  color: white;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.demo-content {
  text-align: center;
  margin-bottom: 30px;
}

.demo-content h2 {
  margin: 0 0 12px 0;
  font-size: 24px;
  font-weight: 700;
}

.demo-content p {
  margin: 0 0 20px 0;
  opacity: 0.9;
  line-height: 1.6;
}

.demo-controls h3 {
  margin: 0 0 12px 0;
  font-size: 16px;
  font-weight: 600;
}

.control-buttons {
  display: flex;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
}

.control-btn {
  padding: 6px 12px;
  background: rgba(255, 255, 255, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 6px;
  color: white;
  font-size: 12px;
  cursor: pointer;
  transition: all 0.3s ease;
}

.control-btn:hover,
.control-btn.active {
  background: rgba(255, 255, 255, 0.3);
  transform: translateY(-1px);
}

.menu-container {
  background: white;
  border-radius: 12px;
  padding: 0;
  margin-bottom: 20px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
  overflow: hidden;
}

.multi-dropdown-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  background: #ffffff;
  border-bottom: 1px solid #e5e7eb;
  position: relative;
  min-height: 60px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 18px;
  color: #1f2937;
}

.brand-icon {
  font-size: 24px;
}

.nav-menu {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 0;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 20px 16px;
  text-decoration: none;
  color: #374151;
  font-weight: 500;
  transition: all 0.3s ease;
  border-bottom: 3px solid transparent;
}

.nav-link:hover,
.nav-link:focus {
  color: #3b82f6;
  background: rgba(59, 130, 246, 0.05);
  border-bottom-color: #3b82f6;
}

.dropdown-icon,
.submenu-icon {
  font-size: 10px;
  transition: transform 0.3s ease;
}

.nav-item.active .dropdown-icon {
  transform: rotate(180deg);
}

.dropdown-menu,
.submenu {
  position: absolute;
  top: 100%;
  left: 0;
  background: white;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
  min-width: 220px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.3s ease;
  z-index: 1000;
  list-style: none;
  margin: 0;
  padding: 8px 0;
}

.submenu {
  top: 0;
  left: 100%;
  margin-left: 8px;
}

.nav-item:hover .dropdown-menu,
.nav-item.active .dropdown-menu,
.dropdown-item:hover .submenu,
.dropdown-item.active .submenu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-item {
  position: relative;
}

.dropdown-link,
.submenu-link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  text-decoration: none;
  color: #374151;
  font-size: 14px;
  transition: all 0.3s ease;
  border-left: 3px solid transparent;
}

.dropdown-link:hover,
.dropdown-link:focus,
.submenu-link:hover,
.submenu-link:focus {
  background: rgba(59, 130, 246, 0.05);
  color: #3b82f6;
  border-left-color: #3b82f6;
}

.item-icon {
  font-size: 16px;
  width: 20px;
  text-align: center;
}

.has-submenu .submenu-icon {
  margin-left: auto;
}

.dropdown-item.active .submenu-icon {
  transform: rotate(90deg);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  cursor: pointer;
  padding: 8px;
  border-radius: 4px;
  transition: background 0.3s ease;
}

.nav-toggle:hover {
  background: rgba(59, 130, 246, 0.1);
}

.hamburger-line {
  width: 20px;
  height: 2px;
  background: #374151;
  transition: all 0.3s ease;
}

.nav-toggle.active .hamburger-line:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active .hamburger-line:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active .hamburger-line:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -6px);
}

.menu-info {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 8px;
  padding: 16px;
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}

.info-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.info-label {
  font-size: 12px;
  opacity: 0.8;
  font-weight: 500;
}

.info-value {
  font-size: 14px;
  font-weight: 600;
}

/* Variaciones de Tema */
.multi-dropdown-nav.dark-theme {
  background: #1f2937;
  border-bottom-color: #374151;
}

.dark-theme .nav-brand,
.dark-theme .nav-link {
  color: #f9fafb;
}

.dark-theme .nav-link:hover,
.dark-theme .nav-link:focus {
  background: rgba(59, 130, 246, 0.2);
}

.dark-theme .dropdown-menu,
.dark-theme .submenu {
  background: #374151;
  border-color: #4b5563;
}

.dark-theme .dropdown-link,
.dark-theme .submenu-link {
  color: #f9fafb;
}

.dark-theme .dropdown-link:hover,
.dark-theme .dropdown-link:focus,
.dark-theme .submenu-link:hover,
.dark-theme .submenu-link:focus {
  background: rgba(59, 130, 246, 0.2);
}

.multi-dropdown-nav.minimal-theme {
  background: #f9fafb;
  border-bottom: none;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.minimal-theme .nav-link {
  border-radius: 6px;
  margin: 0 4px;
}

.minimal-theme .nav-link:hover,
.minimal-theme .nav-link:focus {
  background: #e5e7eb;
  border-bottom-color: transparent;
}

.multi-dropdown-nav.colorful-theme {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-bottom: none;
}

.colorful-theme .nav-brand,
.colorful-theme .nav-link {
  color: white;
}

.colorful-theme .nav-link:hover,
.colorful-theme .nav-link:focus {
  background: rgba(255, 255, 255, 0.2);
  border-bottom-color: white;
}

.colorful-theme .dropdown-menu,
.colorful-theme .submenu {
  background: white;
  border: none;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

/* Responsivo Móvil */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }
  
  .nav-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: white;
    flex-direction: column;
    border-top: 1px solid #e5e7eb;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
    z-index: 999;
  }
  
  .nav-menu.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
  
  .nav-item {
    width: 100%;
  }
  
  .nav-link {
    padding: 16px 20px;
    border-bottom: 1px solid #f3f4f6;
    border-left: none;
  }
  
  .dropdown-menu {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    box-shadow: none;
    border: none;
    border-radius: 0;
    background: #f9fafb;
    display: none;
  }
  
  .nav-item.active .dropdown-menu {
    display: block;
  }
  
  .submenu {
    position: static;
    margin-left: 0;
    background: #f3f4f6;
    display: none;
  }
  
  .dropdown-item.active .submenu {
    display: block;
  }
  
  .dropdown-link,
  .submenu-link {
    padding-left: 40px;
  }
  
  .submenu-link {
    padding-left: 60px;
  }
  
  .menu-info {
    flex-direction: column;
    gap: 12px;
  }
}

/* Estilos de enfoque para accesibilidad */
.nav-link:focus,
.dropdown-link:focus,
.submenu-link:focus,
.nav-toggle:focus {
  outline: 2px solid #3b82f6;
  outline-offset: 2px;
}

/* Animación para elementos del menú */
@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.dropdown-menu .dropdown-item,
.submenu li {
  animation: slideIn 0.3s ease forwards;
}

.dropdown-menu .dropdown-item:nth-child(2) {
  animation-delay: 0.1s;
}

.dropdown-menu .dropdown-item:nth-child(3) {
  animation-delay: 0.2s;
}

.dropdown-menu .dropdown-item:nth-child(4) {
  animation-delay: 0.3s;
}

/* Indicador de hover */
.nav-item::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 3px;
  background: #3b82f6;
  transition: all 0.3s ease;
  transform: translateX(-50%);
}

.nav-item:hover::before {
  width: 80%;
}

/* Estado de carga */
.nav-item.loading {
  opacity: 0.6;
  pointer-events: none;
}

.nav-item.loading::after {
  content: '';
  position: absolute;
  top: 50%;
  right: 8px;
  width: 12px;
  height: 12px;
  border: 1px solid #e5e7eb;
  border-top: 1px solid #3b82f6;
  border-radius: 50%;
  animation: spin 1s linear infinite;
  transform: translateY(-50%);
}

@keyframes spin {
  0% { transform: translateY(-50%) rotate(0deg); }
  100% { transform: translateY(-50%) rotate(360deg); }
}

document.addEventListener('DOMContentLoaded', function() {
  const nav = document.querySelector('.multi-dropdown-nav');
  const navToggle = document.querySelector('.nav-toggle');
  const navMenu = document.querySelector('.nav-menu');
  const navItems = document.querySelectorAll('.nav-item');
  const dropdownItems = document.querySelectorAll('.dropdown-item');
  const controlButtons = document.querySelectorAll('.control-btn');
  const currentTheme = document.getElementById('currentTheme');
  const activeMenu = document.getElementById('activeMenu');
  const menuDepth = document.getElementById('menuDepth');
  
  let currentDepth = 0;
  let activeMenuPath = [];
  
  // Inicializar funcionalidad de dropdown multinivel
  function initMultiDropdown() {
    // Manejar elementos de navegación principal
    navItems.forEach((item, index) => {
      const link = item.querySelector('.nav-link');
      const dropdown = item.querySelector('.dropdown-menu');
      
      if (dropdown) {
        // Eventos de mouse
        item.addEventListener('mouseenter', () => {
          openDropdown(item, 1);
        });
        
        item.addEventListener('mouseleave', () => {
          closeDropdown(item);
        });
        
        // Eventos de clic para móvil
        link.addEventListener('click', (e) => {
          if (window.innerWidth <= 768) {
            e.preventDefault();
            toggleDropdown(item);
          }
        });
        
        // Navegación por teclado
        link.addEventListener('keydown', (e) => {
          handleKeyNavigation(e, item, 'nav');
        });
      }
      
      // Manejar enlaces de navegación regulares
      link.addEventListener('click', (e) => {
        if (!item.classList.contains('has-dropdown')) {
          handleNavClick(link.textContent.trim());
        }
      });
    });
    
    // Manejar elementos del dropdown
    dropdownItems.forEach(item => {
      const link = item.querySelector('.dropdown-link');
      const submenu = item.querySelector('.submenu');
      
      if (submenu) {
        // Eventos de mouse
        item.addEventListener('mouseenter', () => {
          openSubmenu(item, 2);
        });
        
        item.addEventListener('mouseleave', () => {
          closeSubmenu(item);
        });
        
        // Eventos de clic para móvil
        link.addEventListener('click', (e) => {
          if (window.innerWidth <= 768) {
            e.preventDefault();
            toggleSubmenu(item);
          }
        });
        
        // Navegación por teclado
        link.addEventListener('keydown', (e) => {
          handleKeyNavigation(e, item, 'dropdown');
        });
      }
      
      // Manejar clics en enlaces del dropdown
      link.addEventListener('click', (e) => {
        if (!item.classList.contains('has-submenu')) {
          handleMenuClick(link.textContent.trim());
        }
      });
    });
    
    // Manejar enlaces del submenú
    const submenuLinks = document.querySelectorAll('.submenu-link');
    submenuLinks.forEach(link => {
      link.addEventListener('click', (e) => {
        handleMenuClick(link.textContent.trim());
      });
      
      link.addEventListener('keydown', (e) => {
        handleKeyNavigation(e, link.closest('li'), 'submenu');
      });
    });
  }
  
  // Abrir menú desplegable
  function openDropdown(item, depth) {
    closeAllDropdowns();
    item.classList.add('active');
    item.querySelector('.nav-link').setAttribute('aria-expanded', 'true');
    updateMenuInfo(item.querySelector('.nav-link').textContent.trim(), depth);
  }
  
  // Cerrar menú desplegable
  function closeDropdown(item) {
    item.classList.remove('active');
    item.querySelector('.nav-link').setAttribute('aria-expanded', 'false');
    closeAllSubmenus(item);
    updateMenuInfo('Ninguno', 0);
  }
  
  // Alternar dropdown para móvil
  function toggleDropdown(item) {
    const isActive = item.classList.contains('active');
    closeAllDropdowns();
    
    if (!isActive) {
      item.classList.add('active');
      item.querySelector('.nav-link').setAttribute('aria-expanded', 'true');
      updateMenuInfo(item.querySelector('.nav-link').textContent.trim(), 1);
    } else {
      updateMenuInfo('Ninguno', 0);
    }
  }
  
  // Abrir submenú
  function openSubmenu(item, depth) {
    closeAllSubmenus();
    item.classList.add('active');
    item.querySelector('.dropdown-link').setAttribute('aria-expanded', 'true');
    updateMenuInfo(item.querySelector('.dropdown-link').textContent.trim(), depth);
  }
  
  // Cerrar submenú
  function closeSubmenu(item) {
    item.classList.remove('active');
    item.querySelector('.dropdown-link').setAttribute('aria-expanded', 'false');
    
    // Actualizar a información del menú padre
    const parentNav = item.closest('.nav-item');
    if (parentNav) {
      updateMenuInfo(parentNav.querySelector('.nav-link').textContent.trim(), 1);
    }
  }
  
  // Alternar submenú para móvil
  function toggleSubmenu(item) {
    const isActive = item.classList.contains('active');
    closeAllSubmenus();
    
    if (!isActive) {
      item.classList.add('active');
      item.querySelector('.dropdown-link').setAttribute('aria-expanded', 'true');
      updateMenuInfo(item.querySelector('.dropdown-link').textContent.trim(), 2);
    } else {
      const parentNav = item.closest('.nav-item');
      if (parentNav) {
        updateMenuInfo(parentNav.querySelector('.nav-link').textContent.trim(), 1);
      }
    }
  }
  
  // Cerrar todos los dropdowns
  function closeAllDropdowns() {
    navItems.forEach(item => {
      item.classList.remove('active');
      const link = item.querySelector('.nav-link');
      if (link.hasAttribute('aria-expanded')) {
        link.setAttribute('aria-expanded', 'false');
      }
    });
    closeAllSubmenus();
  }
  
  // Cerrar todos los submenús
  function closeAllSubmenus(parent = null) {
    const items = parent ? parent.querySelectorAll('.dropdown-item') : dropdownItems;
    items.forEach(item => {
      item.classList.remove('active');
      const link = item.querySelector('.dropdown-link');
      if (link && link.hasAttribute('aria-expanded')) {
        link.setAttribute('aria-expanded', 'false');
      }
    });
  }
  
  // Manejar navegación por teclado
  function handleKeyNavigation(e, item, type) {
    const items = getNavigationItems(type);
    const currentIndex = Array.from(items).indexOf(item);
    
    switch(e.key) {
      case 'ArrowDown':
        e.preventDefault();
        const nextItem = items[currentIndex + 1] || items[0];
        focusItem(nextItem, type);
        break;
      case 'ArrowUp':
        e.preventDefault();
        const prevItem = items[currentIndex - 1] || items[items.length - 1];
        focusItem(prevItem, type);
        break;
      case 'ArrowRight':
        e.preventDefault();
        if (type === 'nav' && item.classList.contains('has-dropdown')) {
          openDropdown(item, 1);
          const firstDropdownItem = item.querySelector('.dropdown-item');
          if (firstDropdownItem) {
            focusItem(firstDropdownItem, 'dropdown');
          }
        } else if (type === 'dropdown' && item.classList.contains('has-submenu')) {
          openSubmenu(item, 2);
          const firstSubmenuItem = item.querySelector('.submenu li');
          if (firstSubmenuItem) {
            focusItem(firstSubmenuItem, 'submenu');
          }
        }
        break;
      case 'ArrowLeft':
        e.preventDefault();
        if (type === 'dropdown') {
          const parentNav = item.closest('.nav-item');
          if (parentNav) {
            closeDropdown(parentNav);
            focusItem(parentNav, 'nav');
          }
        } else if (type === 'submenu') {
          const parentDropdown = item.closest('.dropdown-item');
          if (parentDropdown) {
            closeSubmenu(parentDropdown);
            focusItem(parentDropdown, 'dropdown');
          }
        }
        break;
      case 'Escape':
        e.preventDefault();
        closeAllDropdowns();
        updateMenuInfo('Ninguno', 0);
        break;
      case 'Enter':
      case ' ':
        e.preventDefault();
        const link = item.querySelector('a');
        if (link) {
          link.click();
        }
        break;
    }
  }
  
  // Obtener elementos de navegación por tipo
  function getNavigationItems(type) {
    switch(type) {
      case 'nav':
        return navItems;
      case 'dropdown':
        return document.querySelectorAll('.dropdown-item');
      case 'submenu':
        return document.querySelectorAll('.submenu li');
      default:
        return [];
    }
  }
  
  // Enfocar en elemento específico
  function focusItem(item, type) {
    const link = item.querySelector('a');
    if (link) {
      link.focus();
    }
  }
  
  // Manejar clics en enlaces de navegación
  function handleNavClick(linkText) {
    showFeedback(`Navegado a: ${linkText}`);
    closeAllDropdowns();
    updateMenuInfo('Ninguno', 0);
  }
  
  // Manejar clics en elementos del menú
  function handleMenuClick(linkText) {
    const cleanText = linkText.replace(/[^\w\s]/g, '').trim();
    showFeedback(`Seleccionado: ${cleanText}`);
    closeAllDropdowns();
    updateMenuInfo('Ninguno', 0);
  }
  
  // Actualizar visualización de información del menú
  function updateMenuInfo(menuName, depth) {
    activeMenu.textContent = menuName;
    menuDepth.textContent = depth;
    currentDepth = depth;
  }
  
  // Alternar menú móvil
  navToggle.addEventListener('click', () => {
    navToggle.classList.toggle('active');
    navMenu.classList.toggle('active');
    
    const isOpen = navMenu.classList.contains('active');
    navToggle.setAttribute('aria-expanded', isOpen);
    
    if (isOpen) {
      showFeedback('Menú móvil abierto');
    } else {
      showFeedback('Menú móvil cerrado');
      closeAllDropdowns();
    }
  });
  
  // Manejadores de control de tema
  controlButtons.forEach(button => {
    button.addEventListener('click', function() {
      const theme = this.getAttribute('data-theme');
      
      // Actualizar botón activo
      controlButtons.forEach(btn => btn.classList.remove('active'));
      this.classList.add('active');
      
      // Actualizar tema de navegación
      nav.className = `multi-dropdown-nav ${theme}-theme`;
      
      // Actualizar información del tema
      const themeNames = {
        default: 'Predeterminado',
        dark: 'Oscuro',
        minimal: 'Minimalista',
        colorful: 'Colorido'
      };
      currentTheme.textContent = themeNames[theme];
      
      showFeedback(`Cambiado a tema ${themeNames[theme]}`);
    });
  });
  
  // Cerrar dropdowns al hacer clic fuera
  document.addEventListener('click', (e) => {
    if (!nav.contains(e.target)) {
      closeAllDropdowns();
      updateMenuInfo('Ninguno', 0);
    }
  });
  
  // Manejar redimensionamiento de ventana
  window.addEventListener('resize', () => {
    if (window.innerWidth > 768) {
      navMenu.classList.remove('active');
      navToggle.classList.remove('active');
      closeAllDropdowns();
    }
  });
  
  // Función de retroalimentación
  function showFeedback(message) {
    const existing = document.querySelector('.demo-feedback');
    if (existing) existing.remove();
    
    const feedback = document.createElement('div');
    feedback.className = 'demo-feedback';
    feedback.textContent = message;
    feedback.style.cssText = `
      position: fixed;
      top: 20px;
      left: 50%;
      transform: translateX(-50%);
      background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
      color: white;
      padding: 12px 20px;
      border-radius: 8px;
      font-size: 14px;
      font-weight: 500;
      z-index: 10001;
      box-shadow: 0 4px 15px rgba(72, 187, 120, 0.3);
      opacity: 0;
      transition: opacity 0.3s ease;
    `;
    
    document.body.appendChild(feedback);
    
    requestAnimationFrame(() => {
      feedback.style.opacity = '1';
    });
    
    setTimeout(() => {
      feedback.style.opacity = '0';
      setTimeout(() => feedback.remove(), 300);
    }, 2500);
  }
  
  // Inicializar
  initMultiDropdown();
  
  // Retroalimentación inicial
  setTimeout(() => {
    showFeedback('¡Prueba pasar el cursor sobre los elementos del menú y usa las teclas de flecha para navegar!');
  }, 1000);
  
  // Exponer API para uso externo
  window.multiDropdownAPI = {
    closeAllDropdowns,
    showFeedback,
    updateMenuInfo
  };
});