.nav-link {
  position: relative;
  display: inline-block;
}

/* Create the underline */
.nav-link::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 15px;
  width: 0;
  height: 2px;
  background-color: currentColor;
  transition: all 0.3s ease;
  transform: translateX(-50%);
}

/* Hover effect */
.nav-link:hover::after {
  width: 75%;
}

/* Active link (always underlined) */
.nav-link.active::after {
  width: 75%;
}