There are many blocks for footer bottom. From Footer Bottom > Add block > choose the block you want to add.
Similar to Footer section, you need to build Footer Bottom by using Col(parent) and child blocks. Please follow this guide
ADVANCE OPTIONS
Border top: Enable/disable border-top option.
Space horizontal/ vertical items: You can change this for both Desktop and Mobile versions.
HEADING OPTIONS
You are allowed to change Font family, Font-size, Line height, Font weight, Letter spacing, Heading margin for the heading of each block.
You can Font size and Font weight for the content.
There are Heading, Text, Link, Link hover, Border color options for you to change.
Please follow this guideline to config Layout, Background, Margin/Padding for the section.