modify size of this black bar, full screen slideshow behind transparent toolbar

Hey y'all, hoping I catch our hero @tuanphan's gaze on this one.  

url is https://www.samrob.com

So I have some custom bits enabling this full bleed slideshow to live behind my transparent nav bar, however, whether I have captions enabled or not, I can't control the height of this black bar at the bottom.  It seems like overhang almost, exactly the height that my image is pushed up into the nav space.   I'd like the bar to be essentially 2 x the text height, just enough black around it to read the caption neatly.

Thanks in advance for anyone's help they can offer!  In return I offer friendship!

Here's everything I have in Custom CSS on the page right now:

.burger-box {
    display: none;
}
/* Nav one line */
.header-title-nav-wrapper {
    flex: 1 0 90%;
}
.header-layout-nav-center .header-nav {
    width: 100% !important;
    flex: 1 1 100%;
.homepage .header-announcement-bar-wrapper {
    background: transparent !important;
    position: absolute !important;
  }}
.page-section.gallery-section {
padding-top: 0px !important;
}
body{
       height:100%;
       background-size:cover;
      }
   html{
       height:100%;
       }

.homepage .header-announcement-bar-wrapper {
  background: transparent !important;}

On 1/7/2023 at 8:31 AM, tuanphan said:

.gallery-fullscreen-slideshow {
    margin-bottom: 60px !important;
}

This rules, thanks @tuanphan!!!   Do you have a link where I can send some $ to thank you ?