The original and ugly code:

```js
const lang = navigator.language || navigator.userLanguage;

if (lang.indexOf("de") == 0)
{
  window.location.href = 'https://gusbemacbe.github.io/suru-plus-folders/de/';
}

# ...

else if (lang.indexOf("es") == 0) 
{
  window.location.href = 'https://gusbemacbe.github.io/suru-plus-folders/es/';
}

else 
{
  window.location.href = 'https://gusbemacbe.github.io/suru-plus-folders/en/';
}

```

I simplified into an elegant condition-based operation:

```js
const lang = navigator.language || navigator.userLanguage;
const url = 'https://gusbemacbe.github.io/suru-plus-folders/'

function detection(lang) 
{
  let languages =
  {
    'de': () => window.location.href = url+'de',
    'es': () => window.location.href = url+'es',
    'fr': () => window.location.href = url+'fr',
    'it': () => window.location.href = url+'it',
    'nl': () => window.location.href = url+'nl',
    'pt-BR': () => window.location.href = url+'pt-br',
    'pt-PT': () => window.location.href = url+'pt-pt'
  }

  return languages(lang);
}

detection(lang);

```

The problem is `else`, that is for needing to trigger to English if there is not another language into which I didn't translate the website. I checked that I could `return languages(lang) ? 'en': () => window.location.href = url+'en'`, but I am not sure that it is right. I also thought of adding `en': () => window.location.href = url+'en'` to `let languages`, but it needs to be an "`else`".