Use element names levelbar, trough, block, and some style classes on the block nodes: .discrete, .continuous, .empty, .level-low, etc.
17f1104 levelbar: Port to use CSS nodes
gtk/gtklevelbar.c | 257 ++++++++++++++++++++++++++++++++++-------------------
1 file changed, 165 insertions(+), 92 deletions(-)
Upstream: git.gnome.org