Griddy Theme: Optimal featured item image size

I noticed that the width is okay for the featured item, as it spans 100% of the box. However, the height is off. The image is not fully shown, the height is not correct and cuts off almost half of the image depending on the image size.

Is there a way to autoformat the image so that it fits the box properly? Or a way to adjust the image to a large thumbnail so the entire image is shown?

The featured item preview image is intentionally cropped so that for potentially tall images, users don't have to scroll to get to the item name and caption. If you want to get rid of the cropped height, delete <p class="crop"> and its closing tag in the index.php file.

By editing the screen.css file I can change the box size for the featured item without issue.

There isn't a way to scale the image as a whole to a large thumbnail size? Instead of cropping it shows the whole image just at a reduced size?

In the screen.css file, set the #featured-item img to whatever height or width you want your thumbnail to be.