use method terraform uses to keep footer at bottom of page

website/source/assets/javascripts/_app/docs.js

@@ -0,0 +1,48 @@
+(function(){
+
+var mainContentMin = 600;
+
+var Init = {
+
+  start: function(){
+    var classname = this.hasClass(document.body, 'page-sub');
+
+    if (classname) {
+      this.addEventListeners();
+    }
+  },
+
+  hasClass: function (elem, className) {
+    return new RegExp(' ' + className + ' ').test(' ' + elem.className + ' ');
+  },
+
+  addEventListeners: function(){
+    var _this = this;
+    //console.log(document.querySelectorAll('.navbar-static-top')[0]);
+    window.addEventListener('resize', _this.resizeImage, false);
+
+    this.resizeImage();
+  },
+
+  resizeImage: function(){
+
+    var header = document.getElementById('header'),
+        footer = document.getElementById('footer'),
+        main = document.getElementById('main-content'),
+        vp = window.innerHeight,
+        bodyHeight = document.body.clientHeight,
+        hHeight = header.clientHeight,
+        fHeight = footer.clientHeight,
+        withMinHeight = hHeight + fHeight + mainContentMin;
+
+    if(withMinHeight <  vp &&  bodyHeight < vp){
+      var newHeight = mainContentMin + (vp-withMinHeight) + 'px';
+      main.style.height = newHeight;
+    }
+  }
+
+};
+
+Init.start();
+
+})();

website/source/assets/javascripts/application.coffee

@@ -4,6 +4,7 @@
 
 #= require lib/Base
 
+#= require _app/docs
 #= require _app/Sidebar
 #= require _app/app
 #= require _app/homepage

website/source/assets/stylesheets/_docs.scss

@@ -6,6 +6,10 @@ body.layout-docs,
 body.layout-intro{
 	background: $light-purple image-url('sidebar-dots.jpg') left 62px no-repeat;
 
+  #main-content{
+    min-height: 600px;
+  }
+
 	>.container{
 		.col-md-8[role=main]{
 			min-height: 800px;

website/source/layouts/inner.erb

@@ -3,7 +3,7 @@
 	<div class="col-md-4">
 		<%= yield_content :sidebar %>
 	</div>  <!-- /col-md-4 -->
-	<div class="col-md-8" role="main">
+	<div id="main-content" class="col-md-8" role="main">
 		<div class="bs-docs-section">
 			<%= yield %>
 		</div>