If you need blurry semi transparent block, without JS not to do while backdrop-filter, which you need, is only supported in Safari 9 and Safari on iOS.
If you are considering a JS solution, dig into the side of the plugins, for example blur.js.
Durward_Osinski answered on July 9th 19 at 11:20
I do not understand what the author wants - transparent block or transparent block?
The picture, which is above an opaque block it is under an opaque block or prozrachnost lpcwstr FTS