be aware that some sites are bi-lingual and so – bi-directional!
it means you can’t just base the alignment / directionality on the initial setup;
The form should read the active language setting, and set alignment when the form is generated;
In my opinion, alignment should not be specified at all; the containing page’s directionality determines anyway the alignment of elements.
Each time I install and configure si-contact-form, i manually delete all the “text-align:left;”