Dynamically setting alignment of header and cells(column) in aw grid

How to set the alignment of the header row and the whole column of cells using javascript?
There is a static code for setting the alignment using the <style> tag. which is

#myGrid .aw-column-1 {text-align:right;}

But I want to set the alignment of header as center dynamically using javascript and also to set the cell alignment(column) to right.