It appears you have a well-structured Git repository with various files, including SVG icons and HTML documents. Here's a brief overview:

backend/node_modules/postcss-unique-selectors/src/index.js

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+'use strict';
+const selectorParser = require('postcss-selector-parser');
+
+/**
+ * @param {string} selectors
+ * @return {string}
+ */
+function generateUniqueSelector(selectors) {
+  /** @type {Map<string, string>} */
+  const uniqueSelectors = new Map();
+
+  /** @type {selectorParser.SyncProcessor<void>} */
+  const collectUniqueSelectors = (selNode) => {
+    for (const node of selNode.nodes) {
+      /** @type {string[]} */
+      const comments = [];
+
+      // Duplicates are removed by stripping the comments and using the results as the Map key.
+      const keyNode = node.clone();
+      keyNode.walk((sel) => {
+        if (sel.type === 'comment') {
+          comments.push(sel.value);
+          sel.remove();
+        }
+      });
+      const key = keyNode.toString().trim();
+
+      const dupeSelector = uniqueSelectors.get(key);
+      if (!dupeSelector) {
+        uniqueSelectors.set(key, node.toString());
+      } else if (comments.length) {
+        // If the duplicate selector has a comment, it is concatenated to the end of the selector.
+        uniqueSelectors.set(key, `${dupeSelector}${comments.join('')}`);
+      }
+    }
+  };
+
+  selectorParser(collectUniqueSelectors).processSync(selectors);
+
+  return [...uniqueSelectors.entries()]
+    .sort(([a], [b]) => (a > b ? 1 : a < b ? -1 : 0))
+    .map(([, selector]) => selector)
+    .join();
+}
+/**
+ * @type {import('postcss').PluginCreator<void>}
+ * @return {import('postcss').Plugin}
+ */
+function pluginCreator() {
+  return {
+    postcssPlugin: 'postcss-unique-selectors',
+    OnceExit(css) {
+      css.walkRules((nodes) => {
+        if (nodes.raws.selector && nodes.raws.selector.raw) {
+          nodes.raws.selector.raw = generateUniqueSelector(
+            nodes.raws.selector.raw
+          );
+        } else {
+          nodes.selector = generateUniqueSelector(nodes.selector);
+        }
+      });
+    },
+  };
+}
+
+pluginCreator.postcss = true;
+module.exports = pluginCreator;