Hi @matthu
As far as I am aware, changing the radio button's colour when it is checked is quite hard to achieve. Even if you switch to different colour themes like green the radio button checked color still will be blue.
We can only achieve different colours if the radio button is inside the page instead of the basic form. Targeting pseudo-elements of the radio buttons is not effective if it is inside the form.
I have spent some time on achieving this using the "filter" property but you need to spend time to understand more about filter property to achieve the exact color you need but for the proof of concept the below will work
In you custom css: try the following
input[type="radio"], input[type="checkbox"]:checked::after{
filter: hue-rotate(220deg) !important;
}
Save> Sync configuration > and browse website. Hit ctrl + F5 to see a change in the colour to green.
Note: You can play around with the hue-rotate attribute to change the colour combination
Output sample:

Hope it helps.
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