Okay so I designed a website for a restaurant and the design is aimed mostly to entice the viewer by using images of the restaurant's platters and foods. Not to say that text is totally non-existent but the design makes it hard to have enough keywords. Most keywords are found in the ALT attribute of image tags and a couple of headers.

The reason as to why I am in this dilemma? I'm still new to web development and at the time I made the design, I didn't really know much about SEO. So I come here in search of help because I have an idea...

Would it be good practice to have hidden SPAN blocks that would help me fill with keywords?

For example a hidden SPAN would have text in bold to help with SEO. Of course, I will play it safe and not exploit this technique if it works. I have searched that this may be considered spamming by search engines and some companies are taking measures to prevent this.

Thanks in advance!