Transparent Background

I am attempting to make the background of rows and widgets transparent.
My knowledge of CSS is quite limited and I cannot make it work using similar solutions that I found on other threads.

First off, Why do the widgets do not have a transparent option to start with?

Anyway, I have a row split in two columns. On the first column I have SiteOrigin-Slider, and on the second I have a SiteOrigin-Call_to_Action. I need to make the row background transparent, and the SiteOrigin-Call_to_Action background transparent.

Inspecting the elements of my page and I can see that I need to make the background-color: (255,255,255, 0.0) for two locations, but I seem not to be able to get the syntax correct or I do not know how to use the CSS Styles in the widgets.

What I tried to do is add this on the CSS Style box in de row widget:

aside#siteorigin-panels-builder-3.widget_siteorigin-panels-builder.well {
background-color (255,255,255, 0.1);
}

And I tried to add this for the SiteOrigin-Call_to_Action:

.so-widget-sow-cta-default-d8b5b01c468c .sow-cta-base {
background-color (255,255,255, 0.1);
}

Neither worked. I have tried adding “!important” on the end as well, with no results.