y-content-between px-lg-3" id="navbarCollapse">
                <div class="navbar-nav mx-auto py-0">
                    <a href="index.html" class="nav-item nav-link">Home</a>
                    <a href="about.html" class="nav-item nav-link">About</a>
                    <a href="course.html" class="nav-item nav-link">Courses</a>
                    <div class="nav-item dropdown">
                        <a href="#" class="nav-link dropdown-toggle active" data-toggle="dropdown">Pages</a>
         