refact!: prepare for transfer

apply @sgoudham's suggestions
ref https://github.com/catppuccin/catppuccin/issues/2696#issuecomment-2707252468

changes:
- removed every styling outside of the colors themselves (i.e. rounding,
  `text-shadow` & `padding`)
- changed the default accent color to `mauve`
- renamed flavour CSS filenames from `<f>.css` to `catppuccin-<f>.css`

Signed-off-by: Adam Perkowski <adas1per@protonmail.com>

themes/theme.css

@@ -5,13 +5,11 @@
 ::-moz-selection {
   background: var(--main-color);
   color: var(--main-background);
-  text-shadow: none;
 }
 
 ::selection {
   background: var(--main-color);
   color: var(--main-background);
-  text-shadow: none;
 }
 
 .mdl-slider-background-upper {
@@ -324,7 +322,3 @@ div[role=presentation].jstree-wholerow-clicked {
 .itemProgressBar.backgroundProgress .itemProgressBarForeground {
   background-color: var(--hover-background) !important;
 }
-
-.nowPlayingInfoControls {
-  padding-left: 10px;
-}