Adding Border or Background to Widget Sidebar

Hi there,

what plugin is being used to create the newsletter form ? Does it have any controls over the HTML it uses ?

Thanks David for your answer. The plugin is https://pl.wordpress.org/plugins/newsletter/

You can try something like this:

.sidebar .widget_newsletterwidget {
    border: 1px solid #000;
    background-color: #2424;
}

And I would suggest using equivalent padding for the sidebar widget:
https://docs.generatepress.com/article/widget-padding/

Thank You Leo! That works! :)

No problem :)