Backbone sticky footer polyfil

application.html.haml

:javascript
  $(function() {
    new Survca.StickyFooter({
      el: 'body',
      headerElem: 'header.global',
      contentElem: 'section#main',
      footerElem: 'footer.global'
    });
  });

sticky_footer.js.coffee

class StickyFooter extends Backbone.View
  initialize: (options) ->
    @contentObj = $(options.contentElem)
    @windowHeight = $(window).height()
    @headerHeight = $(options.headerElem).outerHeight(true)
    @footerHeight = $(options.footerElem).outerHeight(true)

    @contentObj.css('minHeight', @windowHeight - @headerHeight - @footerHeight)

@Survca ||= {}
@Survca.StickyFooter = StickyFooter