CSS Hack: Force vertical center.

application_helper.rb

module ApplicationHelper
  def force_vertical_center(opts={})
    raise ArgumentError, "Missing block" unless block_given?

    capture_haml do
      haml_tag '.vertical-center', opts do
        haml_tag '.inner', &Proc.new
      end
    end
  end
end

site.css.scss

.vertical-center {
  height: 100%;
  width: 100%;
  display: table;

  > .inner { 
    display: table-cell; 
    vertical-align: middle;
  }
}