The bidi.css file has a rule which adds 5px of padding to the left side of the post notice box but the common.css file has a rule which adds 5px of padding to both sides plus the top/bottom, therefore the rule in the bidi.css file has no effect and is surplus.

File:

bidi.css

Delete:

.rtl p.post-notice {

    padding-left: 5px;

}