Rebuild assets

And add `postcss-scss` and fixing some issues.

stylelint.config.js

@@ -0,0 +1,12 @@
+module.exports = {
+  extends: ['stylelint-config-standard'],
+  customSyntax: require('postcss-scss'),
+  plugins: ['stylelint-scss'],
+  rules: {
+    'at-rule-no-unknown': null,
+    'no-duplicate-selectors': null,
+    'font-family-no-missing-generic-family-keyword': null,
+    'no-descending-specificity': null,
+    'scss/at-rule-no-unknown': true,
+  },
+};