Thanks for writing in! Please keep in mind that apart from the sections, rows and columns, each of the Cornerstone elements has its own margins and padding. In the page, you have added several images and each of them has its own bottom margin. You will need to remove it by adding an inline css
margin-bottom: 0; in the style field or by using element spacing classes. For more about element spacing, please check this out: https://theme.co/apex/forum/t/customizations-element-spacing/211
Hope this helps.