On my landing page, I have a portrait image in the content area that uses the default WordPress alignright class: class="alignright size-medium wp-image-157"
However, this image does not resize for mobile devices. This is problematic for smaller viewports. Is there a CSS solution?
there a couple of options, you can either set two images one for mobile (small) and one for desktop (medium). And use the hide on classes listed here for each image accordingly.