[web-client] simple theme: stylelint LESS source files

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

client/simple/.stylelintrc.json

@@ -0,0 +1,17 @@
+{
+  "formatter": "unix",
+  "plugins": [ "stylelint-prettier" ],
+  "extends": [ "stylelint-config-standard-less" ],
+  "rules": {
+    "prettier/prettier": true,
+    "declaration-empty-line-before": null,
+    "no-invalid-position-at-import-rule": null,
+    "property-no-vendor-prefix": null,
+    "selector-no-vendor-prefix": null,
+    "selector-attribute-quotes": null,
+    "shorthand-property-no-redundant-values": null,
+    "at-rule-no-vendor-prefix": null,
+    "selector-id-pattern": null,
+    "selector-class-pattern": null
+  }
+}