This is the official repository for QGIS styles, icons and other resource types that can be shared with the QGIS Resource Sharing Plugin: https://plugins.qgis.org/plugins/qgis_resource_sharing/
If you want to share a resource collection with the QGIS community, or just plan to use the QGIS Resource Sharing Plugin to browse the available collections, please have a look to the online manual: http://www.akbargumbira.com/qgis_resources_sharing/