TWRP 3.0.0.0 dark stock theme with different colors
Just choose between portrait and landscape version, download your color of choice, rename the zip to ui.zip
and place it on your sdcard in TWRP/theme folder.
For downloads Go here its original thread. And thank you to @fichl for his beautiful work.
Its working on s4 mini duos with twrp 3.0.0-0 by @ne0zone75. And it should work on any variants.