 Some " floating " mosques were located above shops . For the first time , the façade of the mosque was aligned with the street and was elaborately decorated . The decorations were in wood , stucco and stone , including marble , with geometrical and floral patterns and arabesques with Samarran and Byzantine origins . The decorations were more complex than the earlier Islamic forms and more carefully adapted to structural constraints . The imposing architecture and decoration of Fatimid buildings such as the al @-@ Hakim mosque provided a backdrop that supported the dual role of the Fatimid caliph as both religious and political leader . 
