This is a simplistic blurry/fade theme with multiple blue colors, i've been using this theme for years and it's a knock-off of a google chrome theme i've used before switching to vivaldi. The original creator this theme is based off is named "davidydevelopment" on the chrome web store, his theme has not been updated since 2015, My version of that theme has a different wallpaper and slightly different shades of color.
Theme features: Square corners, Easy on the eye contrast, A nice blurry blue background.