.navbar-nav .nav-link {
         position: relative;
         transition: color 0.3s ease-in-out;
         }
         .navbar-nav .nav-link::after {
         content: "";
         position: absolute;
         left: 0;
         bottom: -2px;
         width: 100%;
         height: 2px;
         background-color: #007bff;
         transform: scaleX(0);
         transition: transform 0.3s ease-in-out;
         }
         .navbar-nav .nav-link:hover::after {
         transform: scaleX(1);
         }
         .navbar-nav .nav-link:hover {
         color: #007bff;
         }
         header {
         position: fixed;
         top: 0;
         width: 100%;
         background-color: #15523E;
         color: white;
         z-index: 1000;
         transition: top 0.3s;
         }