Just found an amazing free plugin to let you visual draw custom grids in Gutenberg and then you can add your blocks inside. Consider it as a with the ability to design your own grid layouts. It is clearly the best section or I have ever come across till date. This section block will let you choose either the standard column layouts or as mentioned earlier you can draw (literally) any grid layout as you like. There are customization options for the main section as well as each grid area. You can set the background color, background image, margin, padding, etc. There are even responsive controls available to fine-tune the options for tablet & mobile. Truly amazing plugin. Give it a try, it’s completely free.