extern keymap_config_t keymap_config;
-// Each layer gets a name for readability, which is then used in the keymap matrix below.
-// The underscores don't mean anything - you can have a layer called STUFF or any other name.
-// Layer names don't all need to be of the same length, obviously, and you can also skip them
-// entirely and just use numbers.
#define _QWERTY 0
#define _LOWER 1
#define _VIM 2