Hello Sarah,

.map-overlay {
       background-color: rgba(0, 0, 0, 0.85);

}

in customizer -> additional CSS

As you can see the color is specified as a rgb code with an opacity factor of 0.85

Hi which section to be more exact (since there are multiple section types)

Hi Sarah, if you mean this one

https://prnt.sc/tv5zry

the inner dark section has been specified with dark-background background color

the possible parameters are light-grey-background, white-background and dark-background

https://prnt.sc/tv64wd

if you want to customize the color if the page-section is called counters you can specify

#counters section.dark-background {
    background-color: #222 !important;
}

in customizer -> additional CSS, change the value of #222