ags: NixOS compatibility; Partially migrate to new AgsStack syntax

.config/ags/scss/_lib_mixins.scss

@@ -42,7 +42,7 @@ $rounding_large: 1.705rem;
 
 @mixin icon-material {
     // Material Design Icons
-    font-family: "Material Symbols Rounded", "Material Symbols Outlined",
+    font-family: "Material Symbols Rounded", "MaterialSymbolsRounded", "Material Symbols Outlined",
         "Material Symbols Sharp";
 }
 

.config/ags/scss/_material.scss

@@ -1,29 +1,29 @@
 $darkmode: true;
-$primary: #e4b5ff;
-$onPrimary: #471868;
-$primaryContainer: #5f3280;
-$onPrimaryContainer: #f4d9ff;
-$secondary: #d2c1d9;
-$onSecondary: #372c3e;
-$secondaryContainer: #4f4256;
-$onSecondaryContainer: #eedcf5;
-$tertiary: #f4b7ba;
-$onTertiary: #4b2528;
-$tertiaryContainer: #663b3e;
-$onTertiaryContainer: #ffdadc;
+$primary: #ffb1c3;
+$onPrimary: #66002a;
+$primaryContainer: #861c40;
+$onPrimaryContainer: #ffd9e0;
+$secondary: #e4bcc3;
+$onSecondary: #42292e;
+$secondaryContainer: #5c3f45;
+$onSecondaryContainer: #ffd9df;
+$tertiary: #ecbe91;
+$onTertiary: #462a08;
+$tertiaryContainer: #60401d;
+$onTertiaryContainer: #ffdcb9;
 $error: #ffb4a9;
 $onError: #680003;
 $errorContainer: #930006;
 $onErrorContainer: #ffb4a9;
-$colorbarbg: #111012;
-$background: #111012;
-$onBackground: #e7e0e5;
-$surface: #1d1b1e;
-$onSurface: #e7e0e5;
-$surfaceVariant: #4b454d;
-$onSurfaceVariant: #cdc3ce;
-$outline: #968e98;
+$colorbarbg: #130F10;
+$background: #130F10;
+$onBackground: #ecdfe0;
+$surface: #201a1b;
+$onSurface: #ecdfe0;
+$surfaceVariant: #514345;
+$onSurfaceVariant: #d6c1c4;
+$outline: #9f8c8f;
 $shadow: #000000;
-$inverseSurface: #e7e0e5;
-$inverseOnSurface: #322f33;
-$inversePrimary: #784a9a;
+$inverseSurface: #ecdfe0;
+$inverseOnSurface: #362f30;
+$inversePrimary: #a53557;