I inspected the code and noticed the images are wrapped with figure and div tags, so I styled the figure and image to be 100% width, but that didn’t work (can’t style the div tag).
Yes, but using the styles panel. I think that there’s some problems with styling images in RTE using the styles panel. You can go to the blog post > rich text > set the image to full width. See here > Rich text element overview - Webflow University Documentation
Maybe the media styles are conflicting with the css styling from the style panel.