ref="#tab_collapse"  role="tab" data-toggle="pill">折叠</a>
                            <a class="nav-link" href="#tab_dropdowns"  role="tab" data-toggle="pill">下拉菜单</a>
                            <a class="nav-link" href="#tab_forms"  role="tab" data-toggle="pill">表单</a>
                            <a class="nav-link" href="#tab_input_group"  role="tab" data-toggle="pill">输入框组</a>
                            <a class="nav-link" href="#tab_jumbotron"  role="tab" data-toggle="pill">霸