How to add captions to images in a WordPress blog posting?

I have a WordPress blog at https://www.dibsblog.com. I’m trying to figure out how to add captions underneath images in a post. The theme I’m using is called Falling Leaves. I tried to research this, and learned that there is no real way to do captions in strict HTML. The technique for making a caption for a “table” (containing the image) doesn’t work, for whatever reason. From what I’ve read, I need to alter my style.css file to make captions possible. I’ve tried different methods I’ve discovered on the Web, but none of them work. Help! How is it possible to make captions under a picture? (Key point: the picture is embedded in the text, which wraps around it.) I realize that I will have to add something to my style.css file, but I don’t know exactly what to add; and then I need to know which html code will then insert the caption properly.

I guess the only way for anyone to answer this question is to see the contents of my style.css file; to spare you the trouble of getting the Falling Leaves theme yourselves, I’ll paste its style.css file here. What do I add to this, and where? And then what html goes with it? Thanks!

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