Background position

Default values

Classname key	CSS value
t	`top`
b	`bottom`
c	`center`
l	`left`
r	`right`
bl	`bottom left`
br	`bottom right`
tl	`top left`
tr	`top right`
lb	`left bottom`
lt	`left top`
rb	`right bottom`
rt	`right top`