How to change the colour or pattern of the background
Set the background colour
Changes to the background apply to the entire theme. You can not set the background of an individual page.
To set the background colour, click the background icon (1) and set the type menu to colour (2). Click on the colour chip (3) select a colour
If you select a colour from the colour picker (1) the colour will stay fixed. If you select a colour from the theme swatches (2) the colour will change whenever you change the colour swatch (3)
A color swatch is a sampling of colors. You can use the colour swatches panel to set the colours for a theme. To learn more about Colour Swatches click on the link.
Set a background pattern
To set the background texture, click the background icon (1) and set the type menu to image (2).
You can create a repeat pattern easily using a tool like http://bgpatterns.com/
Drag a pattern from the images tab (1) to the image target (2). If you want the image to repeat, tick the boxes for horizontal or vertical repeat (3).
HINT: It's best to avoid using large images in the background - they can make your site very slow to load.
You can download different kind of patterns from here: http://patterns.ava7.com/
To set a gradient, set the type menu to Linear Gradient (1) and then select two different colour from the colour chips (2)