refactored separator to use CeTZ style

src/misc.typ

@@ -4,11 +4,12 @@
 #import "core/draw/sync.typ"
 #import "core/utils.typ": set-ctx
 
-#let _sep(name) = {
+#let _sep(name, ..style) = {
   return ((
     type: "sep",
     draw: separator.render,
-    name: name
+    name: name,
+    style: style.named()
   ),)
 }