The background reflects the basemap you have chosen, which, by default, is Topographic. The Topographic basemap shows physical land features with some built environment features. If you’d prefer another basemap, click the Basemaps icon in the Tool Kit in the lower left side of the map (looks like a stack of papers). Additional basemaps include Street, Terrain, Nat Geo, Canvas, and Imagery. To clearly see your basemap you may need to turn off other layers, particularly Main Maps. To turn off other layers, select No Main Map Selected in Main Maps or uncheck the box next to any layer name in Boundaries & Optional Layers or Population/MAP for MAT Indicators.