You can change the look and feel of the launchpad homepage and launchpad content by choosing a different SAP standard theme or a custom theme created with the UI theme designer.
Administrators can change the SAP default theme for the launchpad in Customizing using the parameter THEME
See Setting Parameters in Customizing.The default theme can be changed:
Using the URL parameter sap-theme
See Setting Parameters in the Launchpad URL.In the personalization settings, provided this option was enabled by an administrator.
See Personalizing the Home Page and Launchpad Configuration Parameters.