diff --git a/frontend/src/layouts/AuthLayout_gdd.spec.js b/frontend/src/layouts/AuthLayout_gdd.spec.js
index 4d74e7941..e4aa10a23 100644
--- a/frontend/src/layouts/AuthLayout_gdd.spec.js
+++ b/frontend/src/layouts/AuthLayout_gdd.spec.js
@@ -55,6 +55,11 @@ describe('AuthLayoutGdd', () => {
       expect(wrapper.findComponent({ name: 'LanguageSwitch' }).exists()).toBeTruthy()
     })
 
+    test('test size in setTextSize ', () => {
+      wrapper.vm.setTextSize('85')
+      expect(wrapper.vm.$refs.pageFontSize.style.fontSize).toBe('85rem')
+    })
+
     // describe('check LanguageSwitch on register page', () => {
     //   beforeEach(() => {
     //     mocks.$route.path = '/register'
diff --git a/frontend/src/layouts/AuthLayout_gdd.vue b/frontend/src/layouts/AuthLayout_gdd.vue
index 5df87f302..b9da71200 100644
--- a/frontend/src/layouts/AuthLayout_gdd.vue
+++ b/frontend/src/layouts/AuthLayout_gdd.vue
@@ -1,5 +1,5 @@
 <template>
-  <div class="auth-template page-font-size">
+  <div class="auth-template" ref="pageFontSize">
     <div v-if="mobilStart" class="mobil-start-box d-inline d-sm-inline d-md-inline d-lg-none">
       <div class="position-absolute h1 text-white zindex1000 w-100 text-center mt-8">
         {{ $t('auth.left.gratitude') }}
@@ -140,7 +140,7 @@ export default {
   },
   methods: {
     setTextSize(size) {
-      document.querySelector('.page-font-size').style.fontSize = size + 'rem'
+      this.$refs.pageFontSize.style.fontSize = size + 'rem'
     },
   },
 }