How to apply colour to the spine of your photobook
Place the desired colour background for the spine across the whole double page. This completely colours the spine too.
Add your own photos on the left and right as backgrounds. If you add the photos first as backgrounds and then add the colour background, the background photos will be deleted and replaced by the new background, as there can only be one background. This also happens if at a later stage you want to add a different background in another colour to the spine. Then you will have to add your background photos to the book cover again.
Now you can continue to customise the cover of your photobook. The background of the text box on the spine should remain transparent so that the background colour of the spine shows through.
Please note that if you try to colour the spine of a photobook using only the background colour of the text box, there will be uncoloured areas above and below the text box (see right), which is not desirable. This is because the text box is smaller than the spine and therefore does not colour it completely. Therefore it is better to use the method described above with a coloured background.