<div class="notice-language-wrap">
  <div class="notice-language">
    <div class="description">
      한국어를 사용하고 계시네요. 한국어로 된 페이지를 보시겠어요?
    </div>
    <a href="https://ko.opgg.team/" class="button" id="go-another-language">
      한국어 페이지 보기
    </a>
  </div>
</div>
<div class="custom-navbar-wrap">
  <div class="custom-navbar">
    <div class="custom-navbar-logo">
      <a href="https://www.opgg.team/">
        <img src="https://opgg-static.akamaized.net/images/gnb/svg/00-opgglogo.svg" alt="logo" class="logo-horizontal" style="height: 22px;"/>
        <img src="https://opgg-static.akamaized.net/icon/Icon-72.png?v3" class="logo-squared">
      </a>
    </div>
    <a href="https://www.opgg.team/business-n-news">Business &amp; News</a>
    <a href="https://www.opgg.team/culture">Culture</a>
    <a href="https://www.opgg.team/growth-program">Growth Program</a>
    <a href="https://www.opgg.team/hiring">Hiring</a> 
  </div>
</div>
<script>
  (function(){
    var userLang = navigator.language || navigator.userLanguage; 
    document.body.id = '';

    setTimeout(function(){
      if (userLang.substr(0, 2) === 'ko') {
        document.body.id = 'body-choose-language-enabled';
      } else {
        console.log(userLang);
        document.body.id = '';
      }
    }, 1000);
    
    // 링크 주소 변경
    var anchor = document.getElementById('go-another-language');
    if (window.location.pathname.match(/^\/([a-z\-]+)/g)){
      anchor.href = "https://ko.opgg.team" + window.location.pathname;
    } else {
      anchor.href = "https://ko.opgg.team";
    }
  })();
</script>

Flat management structure(No hierarchy)