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+---
+title: Enable Strict CSS Modules Type Checking
+impact: MEDIUM
+impactDescription: catches typos in CSS module class names at compile time
+type: capability
+tags: strictCssModules, vueCompilerOptions, css-modules, style-module
+---
+
+# Enable Strict CSS Modules Type Checking
+
+**Impact: MEDIUM** - catches typos in CSS module class names at compile time
+
+When using CSS modules with `<style module>`, Vue doesn't validate class names by default. Enable `strictCssModules` to catch typos and undefined classes.
+
+## Problem
+
+CSS module class name errors go undetected:
+
+```vue
+<script setup lang="ts">
+// No error for typo in class name
+</script>
+
+<template>
+  <div :class="$style.buttn">Click me</div>
+</template>
+
+<style module>
+.button {
+  background: blue;
+}
+</style>
+```
+
+The typo `buttn` instead of `button` silently fails at runtime.
+
+## Solution
+
+Enable `strictCssModules` in your tsconfig:
+
+```json
+// tsconfig.json or tsconfig.app.json
+{
+  "vueCompilerOptions": {
+    "strictCssModules": true
+  }
+}
+```
+
+Now `$style.buttn` will show a type error because `buttn` doesn't exist in the CSS module.
+
+## What Gets Checked
+
+| Access | With strictCssModules |
+|--------|----------------------|
+| `$style.validClass` | OK |
+| `$style.typo` | Error: Property 'typo' does not exist |
+| `$style['dynamic']` | OK (dynamic access not checked) |
+
+## Limitations
+
+- Only checks static property access (`$style.className`)
+- Dynamic access (`$style[variable]`) is not validated
+- Only works with `<style module>`, not external CSS files
+
+## Reference
+
+- [Vue Language Tools Wiki - Vue Compiler Options](https://github.com/vuejs/language-tools/wiki/Vue-Compiler-Options)