diff --git a/README.md b/README.md
index 5ab2628..1ba00b1 100644
--- a/README.md
+++ b/README.md
@@ -13,16 +13,24 @@ npm install -g emmet-ls
 
 #### Configuration 
 
-- [nvim-lspconfig](https://github.com/neovim/nvim-lspconfig)
-  ```lua
-  local lspconfig = require'lspconfig'
-  local configs = require'lspconfig/configs'    
-  local capabilities = vim.lsp.protocol.make_client_capabilities()
-  capabilities.textDocument.completion.completionItem.snippetSupport = true
-
-  lspconfig.emmet_ls.setup({
-      -- on_attach = on_attach,
-      capabilities = capabilities,
-      filetypes = { "html", "css", "typescriptreact", "javascriptreact" },
-  })
-  ```
+##### Example Configuration
+
+With [nvim-lspconfig](https://github.com/neovim/nvim-lspconfig):
+
+```lua
+local lspconfig = require('lspconfig')
+local configs = require('lspconfig/configs')
+local capabilities = vim.lsp.protocol.make_client_capabilities()
+capabilities.textDocument.completion.completionItem.snippetSupport = true
+
+lspconfig.emmet_ls.setup({
+    -- on_attach = on_attach,
+    capabilities = capabilities,
+    filetypes = { 'html', 'typescriptreact', 'javascriptreact', 'css', 'sass', 'scss', 'less' },
+})
+```
+
+##### Supported Filetypes
+
+- `html`, `typescriptreact`, `javascriptreact`, `css`, `sass`, `scss` and `less` filetypes are fully supported.
+- Any other filetype is treated as `html`.
diff --git a/src/server.ts b/src/server.ts
index ff33da1..791ba2f 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -23,17 +23,16 @@ import {
   TextDocumentSyncKind,
 } from "vscode-languageserver/node";
 
-let connection = createConnection(ProposedFeatures.all);
+const connection = createConnection(ProposedFeatures.all);
 
 // Create a simple text document manager.
-let documents: TextDocuments<TextDocument> = new TextDocuments(TextDocument);
+const documents: TextDocuments<TextDocument> = new TextDocuments(TextDocument);
 
 let hasConfigurationCapability: boolean = false;
 let hasWorkspaceFolderCapability: boolean = false;
-let hasDiagnosticRelatedInformationCapability: boolean = false;
 
 connection.onInitialize((params: InitializeParams) => {
-  let capabilities = params.capabilities;
+  const capabilities = params.capabilities;
 
   // Does the client support the `workspace/configuration` request?
   // If not, we fall back using global settings.
@@ -43,11 +42,6 @@ connection.onInitialize((params: InitializeParams) => {
   hasWorkspaceFolderCapability = !!(
     capabilities.workspace && !!capabilities.workspace.workspaceFolders
   );
-  hasDiagnosticRelatedInformationCapability = !!(
-    capabilities.textDocument &&
-    capabilities.textDocument.publishDiagnostics &&
-    capabilities.textDocument.publishDiagnostics.relatedInformation
-  );
 
   const triggerCharacters = [
     ">",
@@ -141,92 +135,76 @@ interface ExampleSettings {
   maxNumberOfProblems: number;
 }
 
-// The global settings, used when the `workspace/configuration` request is not supported by the client.
-// Please note that this is not the case when using this server with the client provided in this example
-// but could happen with other clients.
-const defaultSettings: ExampleSettings = { maxNumberOfProblems: 1000 };
-let globalSettings: ExampleSettings = defaultSettings;
-
 // Cache the settings of all open documents
-let documentSettings: Map<string, Thenable<ExampleSettings>> = new Map();
-
-function getDocumentSettings(resource: string): Thenable<ExampleSettings> {
-  if (!hasConfigurationCapability) {
-    return Promise.resolve(globalSettings);
-  }
-  let result = documentSettings.get(resource);
-  if (!result) {
-    result = connection.workspace.getConfiguration({
-      scopeUri: resource,
-      section: "languageServerExample",
-    });
-    documentSettings.set(resource, result);
-  }
-  return result;
-}
+const documentSettings: Map<string, Thenable<ExampleSettings>> = new Map();
 
 documents.onDidClose((e) => {
   documentSettings.delete(e.document.uri);
 });
 
+// For list of language identifiers, see:
+// https://microsoft.github.io/language-server-protocol/specifications/specification-current/#textDocumentItem
+// For list of supported syntax options, see:
+// https://github.com/emmetio/emmet/blob/master/src/config.ts#L280-L283
+const markupIdentifierOverrides = {
+  // Identifiers not in stylesheetIdentifiers are treated as markup.
+  // Markup languages are treated as html syntax by default.
+  // So html, blade, razor and the like don't need to be listed.
+  javascriptreact: 'jsx',
+  typescriptreact: 'jsx',
+} as { [key: string]: string | undefined };
+const stylesheetIdentifiers = [
+  'css',
+  'sass',
+  'scss',
+  'less'
+];
+
 connection.onCompletion(
   (_textDocumentPosition: TextDocumentPositionParams): CompletionItem[] => {
     try {
-      let docs = documents.get(_textDocumentPosition.textDocument.uri);
+      const docs = documents.get(_textDocumentPosition.textDocument.uri);
       if (!docs) throw "failed to find document";
-      let languageId = docs.languageId;
-      let content = docs.getText();
-      let linenr = _textDocumentPosition.position.line;
-      let line = String(content.split(/\r?\n/g)[linenr]);
-      let character = _textDocumentPosition.position.character;
-      let extractPosition =
-        languageId != "css"
-          ? extract(line, character)
-          : extract(line, character, { type: "stylesheet" });
-
-      if (extractPosition?.abbreviation == undefined) {
+      const languageId = docs.languageId;
+      const content = docs.getText();
+      const linenr = _textDocumentPosition.position.line;
+      const line = String(content.split(/\r?\n/g)[linenr]);
+      const character = _textDocumentPosition.position.character;
+
+      // Non-stylesheet identifiers are treated as markup.
+      const isStylesheet = stylesheetIdentifiers.includes(languageId);
+      // Emmet syntax names are the same as language server identifiers for stylesheets,
+      // but not for markup languages.
+      // Treat markup languages as html if not in markupIdentifierOverrides.
+      const syntax = isStylesheet ? languageId : markupIdentifierOverrides[languageId] ?? 'html';
+      const type = isStylesheet ? 'stylesheet' : 'markup';
+
+      const extractedPosition = extract(line, character, { type });
+
+      if (extractedPosition?.abbreviation == undefined) {
         throw "failed to parse line";
       }
 
-      let left = extractPosition.start;
-      let right = extractPosition.end;
-      let abbreviation = extractPosition.abbreviation;
-      let textResult = "";
+      const left = extractedPosition.start;
+      const right = extractedPosition.end;
+      const abbreviation = extractedPosition.abbreviation;
 
-      const htmlLanguages = [
-        "html",
-        "blade",
-        "twig",
-        "eruby",
-        "erb",
-        "razor",
-        "javascript",
-        "javascriptreact",
-        "javascript.jsx",
-        "typescript",
-        "typescriptreact",
-        "typescript.tsx",
-      ];
+      const emmetConfig = resolveConfig({
+        syntax,
+        type,
+        options: {
+          "output.field": (index, placeholder) =>
+            `\$\{${index}${placeholder ? ":" + placeholder : ""}\}`,
+        },
+      });
 
-      if (htmlLanguages.includes(languageId)) {
-        const htmlconfig = resolveConfig({
-          options: {
-            "output.field": (index, placeholder) =>
-              `\$\{${index}${placeholder ? ":" + placeholder : ""}\}`,
-          },
-        });
-        const markup = parseMarkup(abbreviation, htmlconfig);
-        textResult = stringifyMarkup(markup, htmlconfig);
+      let textResult = "";
+      if (!isStylesheet) {
+        const markup = parseMarkup(abbreviation, emmetConfig);
+        textResult = stringifyMarkup(markup, emmetConfig);
       } else {
-        const cssConfig = resolveConfig({
-          type: "stylesheet",
-          options: {
-            "output.field": (index, placeholder) =>
-              `\$\{${index}${placeholder ? ":" + placeholder : ""}\}`,
-          },
-        });
-        const markup = parseStylesheet(abbreviation, cssConfig);
-        textResult = stringifyStylesheet(markup, cssConfig);
+        const markup = parseStylesheet(abbreviation, emmetConfig);
+        textResult = stringifyStylesheet(markup, emmetConfig);
       }
       const range = {
         start: {