I'm looking into Bootstrap and am wondering about offsetting columns: http://twitter.github.com/bootstrap/scaffolding.html#gridSystem
The documentation says that the columns "should always add up to 12 for each row." Then it gives an example of offsetting columns:
<div class="row">
<div class="span4">...</div>
<div class="span3 offset2">...</div>
</div>
Questions:
To clarify what Rob is saying, what you are missing is that all of the grid examples are using 9 columns. The reason is that the sidebar (side navigation) in the docs is itself taking up 3 columns.
The entire width of the bootstrap documentation is 12 columns, minus 3 for the side navigation, which leaves 9 columns for the grid demo. Make sense?