  when the cursor pass in this button, it displays the submenus-->
                            <button class="dropbtn">Data management</button>
                            <div class="dropdown-content">
                                <!--The Submenus with their url-->
                                 <a href="/geojson/uplift">GeoJSON Uplift</a>
                                  <a href="/geojson/downlift">GeoJSON Downlift</a>
                                <a href="/data/ShpUplift">Shapefile importer</a>
