Reduce Space Between Blocks

Site URL: https://www.dietlind.net/clients

How do I reduce the whitespace between an image block and a markdown block? I have a markdown box with an accordion underneath each logo and I would like to reduce the gap between the logo and the "learn more" markdown box so that the Learn More is closer to the corresponding logo. 

I added this CSS code below but it doesn't reduce the gap enough. Thank you in advanced!

.sqs-block.image-block {
 padding: 0;
}

Add to Home > Design > Custom CSS

.markdown-block h3 {
    margin: 0 !important;
}
.markdown-block p:empty {
    display: none;
}