Bdtyktl

I use Ant Dracula theme for my ubuntu. But selection color is pink color, which I want to change to different color. How can I change?
Theme Link is https://www.gnome-look.org/p/1099856/

and on firefox.

we need to edit the file gtk.css

access the file by

sudo -H nautilus /usr/share/themes/Ant-Dracula/gtk-3.20/gtk.css/ change /usr/share/themes if you stored your file in ~/.themes

find the color #ff79c6 and change it to your preferred color in the initial lines.
it has major effect on themes.

/* GTK NAMED COLORS

   ----------------

   use responsibly! */

/* widget text/foreground color */

@define-color theme_fg_color #f8f8f2;

/* text color for entries, views and content in general */

@define-color theme_text_color #f8f8f2;

/* widget base background color */

@define-color theme_bg_color #1e1f29;

/* text widgets and the like base background color */

@define-color theme_base_color #282a36;

/* base background color of selections */

@define-color theme_selected_bg_color #ff79c6;

/* text/foreground color of selections */

@define-color theme_selected_fg_color #f8f8f2;

/* base background color of disabled widgets */

@define-color insensitive_bg_color #22232e;

/* text foreground color of disabled widgets */

@define-color insensitive_fg_color #8b8c8e;

/* disabled text widgets and the like base background color */

@define-color insensitive_base_color #282a36;

/* widget text/foreground color on backdrop windows */

@define-color theme_unfocused_fg_color #8b8c8e;

/* text color for entries, views and content in general on backdrop windows */

@define-color theme_unfocused_text_color #f8f8f2;

/* widget base background color on backdrop windows */

@define-color theme_unfocused_bg_color #1e1f29;

/* text widgets and the like base background color on backdrop windows */

@define-color theme_unfocused_base_color #2a2c39;

/* base background color of selections on backdrop windows */

@define-color theme_unfocused_selected_bg_color #ff79c6;

/* text/foreground color of selections on backdrop windows */

@define-color theme_unfocused_selected_fg_color #f8f8f2;

/* widgets main borders color */

@define-color borders rgba(25, 26, 34, 0.9);

/* widgets main borders color on backdrop windows */

@define-color unfocused_borders rgba(26, 27, 35, 0.91);

/* these are pretty self explicative */

@define-color warning_color #ff9f39;

@define-color error_color #ff3c3c;

@define-color success_color #4caec3;

there are 67 entries with the color #ff79c6, i have replaced all of them with #456789 in single shot. if you want to try each individual, you have to make trial and error of those 67 entries.

save the file & Close. Reboot to see the change.