doc: theme - make sidebar less eye-catching

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

docs/_themes/searx/static/searx.css

@@ -13,3 +13,18 @@ a:hover {
 p.version-warning {
   background-color: #004b6b;
 }
+
+div.sidebar {
+  background-color: whitesmoke;
+  border-color: lightsteelblue;
+  border-radius: 3pt;
+}
+
+p.sidebar-title, .sidebar p {
+  margin: 6pt;
+}
+
+.sidebar li {
+  list-style-type: disclosure-closed;
+}
+