How to reduce vertical padding in sections?

Site URL: https://www.kevinderntravel.com/

Can someone help me figure out how to customize the vertical padding in sections? If you look at my website, I want to reduce the padding above and below the dark grey section that says "Ready to Get Started?".  I've tried a few different versions of CSS code that I've found here on the forum but none seem to work for me. 

Add to Home > Design > Custom CSS

section#call-to-action-4 .Index-page-content {
    padding-top: 1px;
    padding-bottom: 1px;
}