from minnesota! I would like to inquire about suing a company for sexual discrimination as theirreason for not hiring me please

I applied for a job at a local franchise BP gas station. I spoke with the owner, asked if she'd seen my resume, and told her my years of experience in retail. A few weeks later I noticed she'd hired a new guy. I caught her on a Sunday and asked if she still had my resume, which she responded, yes but I prefer to have a male working at night. They close at 10 pm and its far from an urban area. I reminded her I worked overnights alone in Mesa, AZ; in the same job position. I know I am the best qualified applicant for the job, but was not given the same opportunity because I am female.