Hi

Thanks for contacting us. Do you want to reduce the articles image width?

-Regards.

Yes

Use this custom css

.sppb-carousel-inner>.sppb-item>a>img, .sppb-carousel-inner>.sppb-item>img, .sppb-img-responsive{
    width: 250px !important;
}

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.

Unfortunately, this change also affects other graphics in SP Builder, not just the thumbnails in the article.

Sorry delete my previous CSS and use this one

.sppb-article-img-wrap img{
    width: 250px !important;
}