The default homepage and 4 subpages in the Fixter template demo were created using the SP Page Builder Pro component. Fixter Quickstart comes with a set of predefined page designs that you can use in your projects or build new ones. 

Within this page, you are provided with easy customization functionalities with SP Page Builder. Page layouts are created with pre-built SP Page Builder addon and row/column options. Every addon holds information for particular sections in the layout. You need to customize these addons with your desired contents like images, texts, and designs. You can edit Pages (with Rows, Columns, and addons inside) from the back-end or the front-end.