add footer to challenge panel

public/css/styles.less

@@ -208,5 +208,5 @@ ul {
 }
 
 .button-container {
-  height: 120px;
+  height: 200px;
 }

views/challenges/partials/challenge.jade

@@ -18,11 +18,12 @@
                 .btn.btn-success.btn-large.btn-block.completed-challenge.hidden-element I've completed this challenge
                 .ten-pixel-break
                 .btn.btn-primary.btn-large.btn-block.skip-challenge.hidden-element I want to skip this challenge
-.container
-    .row
-        .col-xs-12.col-sm-12.col-md-8
-            a(href="https://twitter.com/intent/tweet?text=Hey%20@freecodecamp") Tweet us links to your projects.
-            a(href="http://blog.freecodecamp.com", target="_blank") Read our blog.
+    .panel-footer.text-center
+        span Need a break?  
+        a(href="http://blog.freecodecamp.com", target="_blank") Check out our blog
+        |   and  
+        a(href="https://twitter.com/freecodecamp", target="_blank") our recent tweets
+        | .
 
 #complete-dialog.modal
     .modal-dialog.animated.zoomIn.fast-animation