/* Navigation Styles */
.nav {
  background: white;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: 80px;
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
}

.logo {
  font-size: 1.5rem;
  font-weight: bold;
  color: #667eea;
  text-decoration: none;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  letter-spacing: .3px;
  text-decoration: none;
  color: #1c1e22;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-link {
  color: #4a5568;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
}

.nav-link:hover {
  color: #667eea;
}

.cta-button {
  background: #667eea;
  color: white;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  transition: background 0.2s;
}

.cta-button:hover {
  background: #5a67d8;
}

/* Dropdown Navigation */
.nav-dropdown {
  position: relative;
}

.nav-dropdown-toggle {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: #4a5568;
  font-weight: 500;
  cursor: pointer;
  transition: color 0.2s;
}

.nav-dropdown-toggle:hover {
  color: #667eea;
}

.dropdown-arrow {
  font-size: 0.8rem;
  transition: transform 0.2s;
}

.nav-dropdown:hover .dropdown-arrow {
  transform: rotate(180deg);
}

.nav-dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background: white;
  border-radius: 8px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
  padding: 0.5rem 0;
  min-width: 200px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.2s;
  z-index: 1001;
}

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

.nav-dropdown-link {
  display: block;
  padding: 0.75rem 1rem;
  color: #4a5568;
  text-decoration: none;
  font-weight: 500;
  transition: all 0.2s;
}

.nav-dropdown-link:hover {
  background: #f8fafc;
  color: #667eea;
}

.nav-dropdown-link.current {
  color: #667eea;
  background: #eef2ff;
}

/* Mobile Navigation */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  cursor: pointer;
  padding: 0.5rem;
}

.mobile-menu-toggle span {
  width: 25px;
  height: 3px;
  background: #4a5568;
  margin: 3px 0;
  transition: 0.3s;
  border-radius: 2px;
}

.mobile-menu-toggle.active span:nth-child(1) {
  transform: rotate(-45deg) translate(-5px, 6px);
}

.mobile-menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
  transform: rotate(45deg) translate(-5px, -6px);
}

.mobile-nav-menu {
  display: none;
  position: fixed;
  top: 80px;
  left: 0;
  right: 0;
  background: white;
  border-top: 1px solid #e2e8f0;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
  z-index: 999;
  padding: 1rem 0;
  max-height: calc(100vh - 80px);
  overflow-y: auto;
}

.mobile-nav-menu.active {
  display: block;
}

.mobile-nav-link {
  display: block;
  padding: 1rem 2rem;
  color: #4a5568;
  text-decoration: none;
  font-weight: 500;
  border-bottom: 1px solid #f0f0f0;
  transition: background 0.2s;
}

.mobile-nav-link:hover {
  background: #f8fafc;
  color: #667eea;
}

.mobile-research-submenu {
  background: #f8fafc;
  padding-left: 2rem;
}

.mobile-research-submenu .mobile-nav-link {
  padding: 0.75rem 2rem;
  font-size: 0.9rem;
  border-bottom: 1px solid #e2e8f0;
}

.mobile-cta-button {
  display: block;
  margin: 1rem 2rem;
  padding: 0.75rem 1.5rem;
  background: #667eea;
  color: white;
  text-align: center;
  text-decoration: none;
  border-radius: 6px;
  font-weight: 600;
  transition: background 0.2s;
}

.mobile-cta-button:hover {
  background: #5a67d8;
}

/* Responsive Design */
@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }
  
  .mobile-menu-toggle {
    display: flex;
  }
}