The quality of my banner dropped a lot. Is normal?

Thank you very much!! I'll buy you a coffe!

Hello!!!  My website url is https://7eab60-11.myshopify.com/ It is still under construction

Hello! I'm using the DAWN theme. I would like to know how to make the menu transparent, so that it appears above the banner. And after I scroll down the page, I want it to be blurred with color, so it doesn't disappear into the page. SITE EXAMPLE: WW...