enabled nested rules for jss

scm-ui/package.json

@@ -17,6 +17,7 @@
     "i18next": "^11.4.0",
     "i18next-browser-languagedetector": "^2.2.2",
     "i18next-fetch-backend": "^0.1.0",
+    "jss-nested": "^6.0.1",
     "moment": "^2.22.2",
     "node-sass": "^4.9.3",
     "postcss-easy-import": "^3.0.0",

scm-ui/src/index.js

@@ -17,6 +17,12 @@ import { ConnectedRouter } from "react-router-redux";
 
 import { urls } from "@scm-manager/ui-components";
 
+import jss from "jss";
+import jssNested from "jss-nested";
+
+// setup jss and install required plugins
+jss.setup(jssNested());
+
 // Create a history of your choosing (we're using a browser history in this case)
 const history: BrowserHistory = createHistory({
   basename: urls.contextPath