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HTML 

              
                <html lang="en" dir="ltr">
<head>
  <meta charset="UTF-8" />
  <title>RTL Navigation Menu Fix</title>
</head>
<body>
  <div class="container">
    <button id="switch-btn">Switch to Arabic</button>
    <button id="fix-btn" style="display: none;">Apply Fix</button>

    <h1 id="heading">Navigation Menu</h1>

    <!-- Problematic Navigation Menu -->
    <nav>
      <ul class="nav-menu" id="nav-menu">
        <li>Home</li>
        <li>About</li>
        <li>Services</li>
        <li>Contact</li>
      </ul>
    </nav>
  </div>
</body>
</html>
!

CSS 

              
                body {
  font-family: Arial, sans-serif;
  margin: 20px;
  background: #f9f9f9;
}

.container {
  background: #fff;
  padding: 20px;
  border-radius: 8px;
}

#switch-btn,
#fix-btn {
  margin-bottom: 1rem;
  margin-right: 0.5rem;
  padding: 0.5rem 1rem;
  cursor: pointer;
  border: 1px solid #ccc;
  background-color: #eee;
  transition: background 0.3s, color 0.3s, border-color 0.3s;
}

#switch-btn:hover,
#fix-btn:hover {
  background-color: #ddd;
}

#fix-btn.fix-applied {
  background-color: #28a745; /* Green when fix is applied */
  color: white;
  border-color: #28a745;
}

#fix-btn.fix-applied:hover {
  background-color: #218838;
}

/* Problem: Default list order remains LTR in RTL mode */
.nav-menu {
  display: flex;
  gap: 1rem;
  list-style: none;
  padding: 0;
  direction: ltr; /* Default left-to-right order */
}

/* ✅ Fix: Reverse menu order for RTL */
.rtl-fix {
  flex-direction: row-reverse;
}
!

JS 

              
                const switchBtn = document.getElementById('switch-btn');
const fixBtn = document.getElementById('fix-btn');
const heading = document.getElementById('heading');
const navMenu = document.getElementById('nav-menu');
const htmlEl = document.documentElement;

let isEnglish = true;
let fixApplied = false;

switchBtn.addEventListener('click', () => {
  if (isEnglish) {
    // Switch to Arabic (RTL)
    htmlEl.lang = 'ar';
    htmlEl.dir = 'rtl';

    heading.textContent = 'قائمة التنقل';
    switchBtn.textContent = 'Switch to English';

    // Update menu items to Arabic
    navMenu.innerHTML = `
      <li>الرئيسية</li>
      <li>حول</li>
      <li>الخدمات</li>
      <li>اتصل بنا</li>
    `;

    // Show fix button in Arabic mode
    fixBtn.style.display = 'inline-block';
    fixBtn.textContent = 'Apply Fix';
    fixBtn.classList.remove('fix-applied');

    fixApplied = false;
    isEnglish = false;
  } else {
    // Switch back to English (LTR)
    htmlEl.lang = 'en';
    htmlEl.dir = 'ltr';

    heading.textContent = 'Navigation Menu';
    switchBtn.textContent = 'Switch to Arabic';

    // Reset menu to English
    navMenu.innerHTML = `
      <li>Home</li>
      <li>About</li>
      <li>Services</li>
      <li>Contact</li>
    `;

    // Hide fix button in English mode
    fixBtn.style.display = 'none';
    fixBtn.classList.remove('fix-applied');

    fixApplied = false;
    isEnglish = true;
  }

  // Reset Fix when switching languages
  navMenu.classList.remove('rtl-fix');
});

fixBtn.addEventListener('click', () => {
  if (!fixApplied) {
    navMenu.classList.add('rtl-fix');
    fixBtn.textContent = 'Fix Applied';
    fixBtn.classList.add('fix-applied');
    fixApplied = true;
  } else {
    navMenu.classList.remove('rtl-fix');
    fixBtn.textContent = 'Apply Fix';
    fixBtn.classList.remove('fix-applied');
    fixApplied = false;
  }
});
!
999px

Console