<nav class="navbar navbar-custom navbar-dark navbar-expand-sm">
            <a class="navbar-brand" href="#">OnlineStore</a>
            <button class="navbar-toggler" data-toggle="collapse" data-target="#navbarMenu">
                <span class="navbar-toggler-icon"></span>
            </button>
            <form class="form-inline mx-auto">
                <div class="input-group">
                    <input class="input-custom form-control" type="search" placeholder="Search" />
                    <div class="input-group-append">
                        <button class="btn btn-custom" type="submit"><i class="fa fa-search"></i></button>
                    </div>
                </div>
            </form>
            <div class="collapse navbar-collapse" id="navbarMenu">
                <ul class="navbar-nav">
                    <li class="nav-item">
                        <a class="nav-link" href="#">My Account</a>
                    </li>
                    <li class="nav-item">
                        <a class="nav-link" href="#">Favorites</a>
                    </li>
                    <li class="nav-item">
                        <a class="nav-link" href="#">My Shopping Card</a>
                    </li>
                </ul>
            </div>
        </nav>