Entry Image Alignment Problem [SOLVED]

[airealataiel]

Hello,

I'm having an issue with the images in my entries. Everything is fine except that when an image is bigger than the entry area, it goes outside of the boundaries (and consequently, it overlaps with my sidebar).

Is there anything I can add (I don't have a custom theme layer, just CSS edits) that will make the pictures automatically resize so that they will fit inside the boundaries, or anything else I can do to fix this?

Thanks!