Tweak CSS on profile page (#289)

I just manually linked a Twitter account for @readthedocs, in view of
his burgeoning campaign. This pointed up a couple CSS rough edges, which
I'm fixing here.

www/%participant_id/index.html

@@ -73,14 +73,6 @@
 {% extends templates/participant.html %}
 {% block their_voice %}
     <style>
-        H2 {
-            margin-bottom: 27pt ! important;
-        }
-        H2.editing {
-            position: relative;
-            top: -3pt;
-            margin-bottom: 24pt ! important;
-        }
         #matrix TR.not-over BUTTON.empty {
             background: transparent;
             color: #F7F7F6;
@@ -134,6 +126,9 @@
             text-align: right;
             width: 6pc;
         }
+        LI {
+            margin-bottom: 1em;
+        }
     </style>
     <script>
         $(document).ready(function()