CSS导航菜单滑动动画实现教程

@keyframes slideIn {
  from {
    transform: translateX(-100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

.nav-menu {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  gap: 20px;
  animation: slideIn 0.6s ease-out forwards;
}

.nav-menu li {
  opacity: 0;
  animation: slideInItem 0.5s ease-out forwards;
}

.nav-menu li:nth-child(1) { animation-delay: 0.1s; }
.nav-menu li:nth-child(2) { animation-delay: 0.2s; }
.nav-menu li:nth-child(3) { animation-delay: 0.3s; }
.nav-menu li:nth-child(4) { animation-delay: 0.4s; }

@keyframes slideInItem {
  from {
    transform: translateX(-20px);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

.dropdown-menu {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}

.nav-item:hover .dropdown-menu {
  max-height: 200px;
  animation: slideDown 0.4s ease forwards;
}

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}