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My img is blurry

As you can see I am working on a blog using collections. I am taking a course in which you pull the photo as a background img and then style it so that it looks clear. How can I make the img look clear and not fuzzy?
Here is the link : https://preview.webflow.com/preview/romels-five-star-project?utm_medium=preview_link&utm_source=designer&utm_content=romels-five-star-project&preview=2166929e87147e35f29054041b260df0&pageId=5f6798adaf81751be86d6bdc&itemId=5f679af0665bc833d893982b&mode=preview