Reorganize admin.css and overhaul button/link/flash visual hierarchy

Sorts rules by hierarchy (base -> layout -> navigation -> buttons ->
tables -> forms -> components), consolidates three duplicated media
query breakpoints into one each, and adds section comments. Bundled
with this reorganization, since the file was rewritten wholesale:

- form.button_to.state_changing: new tinted-pill variant (blue) for
  Publish/Restore/Unlock/Revoke, matching .destructive's pattern
- form.button_to.destructive: now a tinted pill at rest instead of
  plain colored text, consistent padding at rest and on hover
- Scoped wavy-underline link-visibility fix for #page_editor,
  table.node_table, table.assets_table, table.events_table,
  table.user_table, .add_child_links, and the dashboard draft list
- #flash decoupled from the page's structural nav-to-content spacing
  (.admin_content_spacer), which the flash div was silently providing
  as a side effect whenever it rendered

1 files changed, 3 insertions, 1 deletions

diff --git a/app/views/layouts/admin.html.erb b/app/views/layouts/admin.html.erb
index a7ce68a..340eaf2 100644
--- a/app/views/layouts/admin.html.erb
+++ b/app/views/layouts/admin.html.erb
@@ -29,13 +29,15 @@
           <%= yield :subnavigation %>
         </div>
       </div>
-      <div style="clear: both;"></div>
+      <div class="admin_content_spacer"></div>
+      <% if flash[:notice].present? || flash[:error].present? %>
       <div id="flash">
         <%= flash[:notice] %>
         <% if flash[:error] %>
           <span id="flash_error"><%= flash[:error] %></span>
         <% end %>
       </div>
+      <% end %>
       <div id="content">
         <%= yield %>
       </div>