ruzzy

not tested:
1) /Numix/cinnamon/img/misc/calendar-today.svg ( find in other theme and replace? )
2) in cinnamon.css try remove this line: border-image: url("img/panel/DND__panel-bottom__side.svg") 4; - Dec 21 2018

My screen resolution is fullhd, for low resolution need decrease font size. - Dec 19 2018

Hi, try edit cinnamon/cinnamon.css font-size - Dec 19 2018

for gdm login: mv /usr/share/gnome-shell/gnome-shell-theme.gresource /usr/share/gnome-shell/gnome-shell-theme.gresource.backup && cp /usr/share/themes/Matcha-R/gnome-shell/gnome-shell-theme.gresource /usr/share/gnome-shell/gnome-shell-theme.gresource - Jul 13 2018

http://ftp.gnome.org/pub/gnome/sources/gtk+/3.14/

get your version

untar

cd /gtk+-3.14.*/gtk/resources/theme/Adwaita/

modify _colors.scss

run parse-sass.sh (install dependency)

it creates new file gtk-contained.css and gtk-contained-dark.css

modify gtk.css
from
@import url("resource:///org/gtk/libgtk/theme/Adwaita/gtk-contained.css");
to
@import url("gtk-contained.css");

and gtk-dark.css
from
@import url("resource:///org/gtk/libgtk/theme/Adwaita/gtk-contained-dark.css");
to
@import url("gtk-contained-dark.css");

rename folder /gtk+-3.14.*/gtk/resources/theme/Adwaita/
to
gtk-3.0

copy gtk-3.0 folder
into your new theme folder es: Adwaita-hack

you can copy other theme file and folder ( gtk-2.0 index.theme metacity-1 )
from
/usr/share/themes/Adwaita/

you can edit gtk-2.0/gtkrc file to match gtk-3.0 colors

adjust index.theme to match your new theme name

for scrollbar and other object you can use gimp to modify image inside gtk-2.0 subfolder

I don't know if it's the best way, but it works for me ;)

I think you can modify also other _*.scss file, but you pay attention - Dec 22 2014

gnome 3.10 - Oct 14 2014