Issue #8: Done.

src/views/Login/index.vue

@@ -78,7 +78,7 @@ export default {
     * if input no value , disabled.
     */
     isDisabledButton() {
-      let inputAreSpaces = this.auth.username === '' || this.auth.password === '';
+      let inputAreSpaces = this.auth.username === '' || this.auth.password === '' || this.isInvalid === true;
       return this.isDisabled = inputAreSpaces ? true : false;
     },
   },