Script Installed Themes: Yaru-Colors-master terminal Gtk WARNING for some colors

[maddenjmf]

I installed Yaru-Colors-master successfully and the Themes, Applications setting works with all installed color variants of Yaru. However when switching to standard and dark variants only (error does not occur with light variants), I get the following message display in terminal when switching to the problem themes:

(gnome-tweaks:3749): Gtk-WARNING **: 01:32:00.488: Theme parsing error: gtk.css:5449:34: Invalid name of pseudo-class

I have checked the theme folders for inconsistencies but I can't spot any. Most of them have a gnome-shell folder, 3 gtk version folders, a unity folder and an index.theme.

1) I am new to Linux and am trying to identy what is causing the message in the open terminal when gnome-tweaks is run from it and left open? Although the changes are functioning, I'm trying to understand how the system works.
2) How is gnome-shell folder and contents for themes different to that of gtk folder? My Appearance: Shell setting through gnome tweaks tool seems to have no effect on anything even though the list is populated with the themes available from Yaru-Colors-master.

The error displays itself each time I switch to a standard color theme or a dark color theme, but does not present itself when I select any light theme color variant.

If I try to close the terminal after the message appears, it says a process is running and that closing terminal will kill it. I close the terminal and it forces gnome-tweaks to close with it.

Thanks in advance for and help and better understanding you can give me of why this is occuring.

gnome version:
3.36.2

gnome-tweaks --version
3.34.0

Ubuntu 20.04 LTS Desktop

EDIT* Added info in case it is relevant:
I created directories for themes in home/user/.themes and icons in home/user/.icons
The per-existing themes I noticed are in usr/share/themes

[deadflowr]

The error is in the gtk.css file. My guess is line 5449.
File most likely found in the gtk-3.0 folder. Maybe in gtk-3.20 if existing.

Other than that how'd you install the theme, and from where?

[maddenjmf]

There are gtk.css in more than one folder, so I was wondering how to read the numerical code in the error message to identify the exact file (if possible).

**edit: for example, there is one gtk.css in the 3.00 folder and the 3.20 folder with exact same name, for one individual theme.

It was a .zip download from gnome-look.org and I downloaded the .zip to download.

I then ran the install.sh contained within the unzipped folder, and as part of the script it asked me for a path to store the themes and icons.

[maddenjmf]

No other information regarding identifying my exact problem here and understanding the error code?