Fix a constant width for first sidebar and second sidebar
My guess, before your css editing, the index block filled that white space, right?

you changed the width of the sidebar's content, rather than the sidebar itself (which is a region, not a block)

i don't know of the zero point theme, but look for an outer class, like .sidebar, or .sidebar-first, and set the with of that.



i looked into that particular theme.

revert all the css editing and go to the theme settings, under "layout setting -> sidebars layout" try using the 'fixed' options instead than the 'variable'.