How to fix UI 2D Textures Quality?

When I add my texture to the UI and run the game with a higher resolution, the quality of the game deteriorates. Although the icon has a resolution for FULL HD resolution.
Exmaple: Imgur: The magic of the Internet
Also I have 1 pixel border between this BG. But in small resolution it don’t draw. Width = 1 pixel.
1920x1080: Imgur: The magic of the Internet
1320x720: Imgur: The magic of the Internet
How do I best make textures so that they appear equally in all resolutions? If white borders are BORDER, they should work like a vector.