See Avoiding Site Builder CSS for more information on what you should avoid when adding your own custom styles.
A page is a grid of modules that are grouped into rows, columns, and positions.
"Columns Area" contains "Rows"
"Rows" which contain "Columns"
"Columns" contain "Modules"
This is the main "Site Builder" zone that contains all the rows, columns and modules that you can added to a page
<div class="columns" class="columns-inner clearfix">
These are block-level elements that are stacked on top of each other
These are percentage-width elements that are floated left within a Row
<div class="sb-col" style="width:50%">...</div><div class="sb-col" style="width:50%">...</div>
These are the individual modules that contain the content added to the page
Class or ID
This is the same for all modules
This variable class is set based on the type of module (i.e.
This variable id is unique to this particular module - This will not be repeated on the same page or any other page on the Site.
<div id="sb-module-<module_id>" class="sb-module sb-<modulename>"></div>