fixed some css glitches at the #share_with popup

public/stylesheets/sass/application.sass

@@ -2187,8 +2187,7 @@ h3,h4
     :top -0.2em
 
 #share_with
-  :min-width 400px
-  :max-width 400px
+  :min-width 430px
 
   .avatar
     :width 50px
@@ -2427,6 +2426,8 @@ ul.show_comments
     p
       :padding
         :left 1em
+      input[type='text']
+        :width 60%
 
       &.checkbox_select
         label