[fix] check for parent_component before accessing root

src/runtime/internal/Component.ts

@@ -38,7 +38,7 @@ interface T$$ {
 	on_destroy: any[];
 	skip_bound: boolean;
 	on_disconnect: any[];
-	root:Element|ShadowRoot
+	root:null|Element|ShadowRoot
 }
 
 export function bind(component, name, callback) {
@@ -130,10 +130,10 @@ export function init(component, options, instance, create_fragment, not_equal, p
 		callbacks: blank_object(),
 		dirty,
 		skip_bound: false,
-		root: options.target || parent_component.$$.root
+		root: options.target || (parent_component ? parent_component.$$.root : null)
 	};
 
-	append_styles && append_styles($$.root);
+	append_styles && $$.root && append_styles($$.root);
 
 	let ready = false;