WHen you don't know, there is no need to ask.
You will never go wrong dressing for any office-job interviews in a way which reflects your respect for the company, and for the people you will be working with - neatly, cleanly, conservatively. So what covers that?
It is always respectful and appropriate to wear black, dark navy, charcoal or dark tan/brown slacks (or dress/skirt for lady) either with or without a jacket (matching or complementary). For a man, add a long-sleeved shirt with conservative tie if you have one, open one button at the collar if you don't), dark or matching socks and dark shoes, black being most common. IT MUST ALL BE CLEAN and not smelly (that should be obvious but best to mention these days I suppose since some guys will just throw on what they wore yesterday).
For a woman, either matching or complementary jacket can be substituted for an attractive sweater that either matches or compliments the colour of the pants/skirt. Add a long-sleeved blouse or shirt (can be short-sleeved if under another garment) in white or a light pastel colour with a MODEST and non-revealing or no cleavage (your breasts aren't applying for the job, no need to show them).
As for the rest, nude nylons if a woman is wearing a skirt, thin dark or matching dress socks if you're wearing pants, and dark or matching shoes. NO HOOKER HEELS or clubbing shoes (that should not need stating but saying it anyway), wear either flats, or a heel no higher than two inches unless you are VERY petite. THen wear a higher heel in a conservative shoe.
Any male or female jewelry should not be flashy. School rings, family rings, stud earrings or small hoop earrings for ladies, sorry, no earrings for men. As for piercings, one should not wear piercing jewelry (unless it is tasteful and part of your culture) to an interview but if you are hired and they are worn on the job site, you can go from there.