the scripts converts small bitmaps to gtk3 css gradient definitions - direction at the moment only from bottom to top.
Please downsize the icon before to 10 px heigth and remove border.
bash png2css yourimage.png> yourimage; bash yourimage > yourimage.css; rm yourimage; rm y.txt
Perhaps someone could add something to do automatic downsize.
requires awk imagemagick bash cat identify
Why this script ? to speed up development of gtk3 themes.
Do try to get the images gradient with gimp. Its an unexact and time intensive task.
Why no screenshot? well its an script.