The pagination button will be disabled if there is nothing to show in next page. For example assume you configured data grid to show 10 records / rows on each page, if you only have 10 records in your database then the pagination buttons will be disabled. As soon as you have 11 records then the pagination next button will be enabled automatically.
If you want to change the look and feel of pagination buttons then you need to add custom styles in your SASS and compile it to css using Calypso. Have a look at this forum post to see an example on how to add custom styles. You can also go through Style your App with CSS learning path if you want to learn further.
Hope this helps and makes sense!
data is there i am sharing screen shot and i am not select 10 records kind of.