Hello,
You can have a look on this method to add your own css command, here.
www.hikashop.com/support/documentation/2...by-color.html#custom
Now, some advice in order to be sure to prioritize your own css command thanks to a good selector :
1. First the minimum necessary to function properly :
Check that your selector is well written, good class (or Id) html and no mistake or typo
If your command is visible in your browser inspector tool, but is overridden (css command crossed out), then his priority isn't strong enough.
2. Now, some css priority system explanation :
From less to the highest priority :
.html_class_element {command: value}
.html_class_module .html_class_element {command: value}
.html_class_page .html_class_module .html_class_element {command: value}
.html_class_page .html_class_module .html_class_element {command: value !important;}
Note, that if
2 css commands have strictly the
same selector, then the
last written in the css file will be the one used.
Hope this will help you to achieve what you need.
Regards