How to make such a blend in illustrator?

Question

Adobe Illustrator

how to make the edges on the hood with a lock so blurry, I make two wide rectangles and make them transparent by 100% and ctrl + alt + B

Answer 1

Make on the basis of rectangles not with a fill, but with a stroke. One with a smaller thickness (start with 2 pixels), the second with a larger thickness and 0% opacity. After creating a blend, edit the number of steps in it (set, for example, 25).