diff --git a/frontend/src/admin/AdminOidcDetail.vue b/frontend/src/admin/AdminOidcDetail.vue
index 2eb698f..6b6396f 100644
--- a/frontend/src/admin/AdminOidcDetail.vue
+++ b/frontend/src/admin/AdminOidcDetail.vue
@@ -15,15 +15,22 @@ const emit = defineEmits(['save', 'cancel', 'delete', 'resetSecret', 'createPerm
 const authStore = useAuthStore()
 const headerRef = ref(null)
 
+// Helper function to build URLs
+function authSitePath(path) {
+  const url = new URL(authStore.settings.auth_site_url)
+  url.pathname = path
+  return url.toString()
+}
+
 // Local form state
 const name = ref('')
 const redirectUris = ref('')
 const clientSecret = ref(null)
 
 // Computed
-const discoveryUrl = computed(() => `${window.location.origin}/.well-known/openid-configuration`)
 const clientId = computed(() => props.client?.client_id || props.client?.uuid || '')
-const iconUrl = computed(() => `${authStore.settings.auth_site_url}/favicon.ico`)
+const discoveryUrl = computed(() => authSitePath('/.well-known/openid-configuration'))
+const iconUrl = computed(() => authSitePath('/favicon.ico'))
 
 // Groups (permissions) scoped to this client
 const clientGroups = computed(() => {