OpenMapTiles comes with a variety of different styles optimized for the OpenMapTiles vector tile schema. The styles and schema are free and open-source and you can adapt the design and code for your project or commercial product however you like, if you keep the copyright attributtion. You can either use the styles directly as basemap or as starting point for your own map style.
The same style can be used in client based maps with Mapbox GL JS or OpenLayers, on native Android/iOS mobile apps as well as in raster maps for print and older clients like Leaflet thanks to Tileserver GL.
Klokantech Basic is basemap which tries to stay in the background and only give the most relevant information.
OSM Bright is a general purpose base map showcasing the great detail of OpenStreetMap data. It is a good starting point for your own complex base maps.
Positron is beautiful light base map which is ideal for a non obtrusive basemap for your data visualizations. The cartography by Stamen Design is licensed under CC0.
Dark Matter is a dark base map and a good starting point for other darker designs. The cartography by Stamen Design is licensed under CC0.
A Map showcasing 3D buildings.
A basic map style showing the contour lines and hillshading from OpenMapTiles.com.
A blue basemap for visualizations.
Port of the Stamen Maps Toner style.
A free Mapbox GL basemap style for everyone with complete liberty to use and self host. OSM Liberty is a fork of OSM Bright based on free data sources with a mission for a clear good looking design for the everyday user.
OpenMapTiles vector tiles can be styled also with CartoCSS and rendered with Mapnik. You can edit these styles in Mapbox Studio Classic desktop application and use TileServer-Mapnik to generate raster tiles from vector tiles and the TM2 style.