Hi there!

Thanks for your query.

Are you talking about the active color for your thumb slider on the right?

If yes, you are trying the right code but there is an extra hash(#) in your code, that may causing problem.

However, you may try the following code in your custom CSS:

.sppb-addon-articles-thumb-slider .articles-thumb .swiper-slide-thumb-active {
    background-image: linear-gradient(90deg, #cc0000 0%, #cc0000 108%)!important;
}
.sppb-addon-articles-thumb-slider .articles-thumb .swiper-slide-thumb-active .article-counter {
    background-color: #cc0000 !important;
}

Hope this will serve your purpose.

Note: Path towards custom CSS: Extensions>Templates>Styles> Click on your current default template name then choose Template Options. Then find custom CSS within the custom code.

Best Regards

Thanks a lot.... Hah.... seems crazy. i checked it twice. However yes. i missed # and important. Thanks.

Glad that it helped and you are always welcome:)

You may accept the most useful answer in order to close the post.

Excellent

Thank you so much for your kind words.

Good comments and 5 start reviews lifts us up so high:)