added css linter workflow

.forgejo/workflows/csslint.yaml

@@ -0,0 +1,13 @@
+name: Lint CSS
+
+on:
+  push
+
+jobs:
+  lint:
+    runs-on: docker
+    steps:
+    - name: Checkout Repository
+      uses: actions/checkout@v3
+    - name: Lint CSS
+      uses: https://github.com/marketplace/actions/stylelinter@master

Snippets/Fonts/FiraCode.css

@@ -1,5 +1,5 @@
 @import url('https://fonts.googleapis.com/css2?family=Fira+Code&display=swap');
 
 :root {
-  --font-monospace: "fira code";
+  --font-code: "fira code";
 }