CSS水平导航栏下划线动画实现方法

.navbar {
  display: flex;
  gap: 30px;
  padding: 20px;
  background-color: #f8f8f8;
}

.nav-link {
  text-decoration: none;
  color: #333;
  position: relative;
  font-size: 16px;
}

.nav-link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -5px;
  width: 0;
  height: 2px;
  background-color: #007bff;
  transition: width 0.3s ease;
}

.nav-link:hover::after {
  width: 100%;
}

.nav-link::after {
  content: '';
  position: absolute;
  left: 50%;
  bottom: -5px;
  width: 0;
  height: 2px;
  background-color: #007bff;
  transition: width 0.3s ease, left 0.3s ease;
}

.nav-link:hover::after {
  width: 100%;
  left: 0;
}

.nav-link::after {
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 0.3s ease;
}
.nav-link:hover::after {
  transform: scaleX(1);
}