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HTML

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="container ">
  <div class="row mt-3">
  <div class="col">
  
  <nav>
  <ul class="nav nav-tabs" role="tablist">
    <li class="nav-item"><a href="#" id="tab1" class="nav-link active" data-bs-toggle="tab" data-bs-target="#page1" type="button" role="tab" aria-controls="page1" aria-selected="true">One One-Thousand</a></li>
    <li class="nav-item"><a href="#" id="tab2" class="nav-link" data-bs-toggle="tab" data-bs-target="#page2" type="button" role="tab" aria-controls="page2" aria-selected="false">Two One-Thousand</a></li>
    <li class="nav-item"><a href="#" id="tab3" class="nav-link" data-bs-toggle="tab" data-bs-target="#page3" type="button" role="tab" aria-controls="page3" aria-selected="false">Three to Get Ready</a></li>
    <li class="nav-item"><a href="#" id="tab4" class="nav-link" data-bs-toggle="tab" data-bs-target="#page4" type="button" role="tab" aria-controls="page4" aria-selected="false">Four to Go</a></li>
    <li class="nav-item"><a href="#" id="tab5" class="nav-link" data-bs-toggle="tab" data-bs-target="#page5" type="button" role="tab" aria-controls="page5" aria-selected="false">Five to Something Else</a></li>
    <li class="nav-item"><a href="#" href="#" id="tab6" class="nav-link" data-bs-toggle="tab" data-bs-target="#page6" type="button" role="tab" aria-controls="page6" aria-selected="false"> Six</a></li>
  
    <div id="nav-buttons" class="pull-right">
      <div id="tabDropdown" class="btn-group btn-group-sm">
       <div id="tabDrop" class="nav-link dropdown-toggle" type="button" id="dropdownMenu" data-bs-toggle="dropdown">
        <i class="bi bi-list"></i>
       </div>
       <ul class="dropdown-menu">
         <li><a href="javascript:void(0)" class="dropdown-item" data-bs-toggle="tab" data-bs-target="#page1">One One-Thousand</a></li>
         <li><a href="javascript:void(0)" class="dropdown-item" data-bs-toggle="tab" data-bs-target="#page2">Two One-Thousand</a></li>
         <li><a href="javascript:void(0)" class="dropdown-item" data-bs-toggle="tab" data-bs-target="#page3">Three to Get Ready</a></li>
         <li><a href="javascript:void(0)" class="dropdown-item" data-bs-toggle="tab" data-bs-target="#page4">Four to Go</a></li>
         <li><a href="javascript:void(0)" class="dropdown-item" data-bs-toggle="tab" data-bs-target="#page5">Five to Something Else</a></li>
         <li><a href="javascript:void(0)" class="dropdown-item" data-bs-toggle="tab" data-bs-target="#page6">Six</a></li>
       </ul>
     </div>   
   </div>
    
  </ul>
  </nav>
    
  <div class="tab-content mt-3 pt-3" >
    <div id="page1" class="tab-pane fade show active" role="tabpanel" aria-labelledby="tab1" tabindex="0" >
      <h1 class="text-center" >First we have 1</h1>
    </div>
    <div id="page2" class="tab-pane fade" role="tabpanel" aria-labelledby="tab2" tabindex="0" >
      <h1 class="text-center" >There was 2</h1>
    </div>
    <div id="page3" class="tab-pane fade" role="tabpanel" aria-labelledby="tab3" tabindex="0" >
      <h1 class="text-center" >Content of 3</h1>
    </div>
    <div id="page4" class="tab-pane fade" role="tabpanel" aria-labelledby="tab4" tabindex="0" >
      <h1 class="text-center" >4</h1>
    </div>
    <div id="page5" class="tab-pane fade" role="tabpanel" aria-labelledby="tab5" tabindex="0" >
      <h1 class="text-center" >5</h1>
    </div>
    <div id="page6" class="tab-pane fade" role="tabpanel" aria-labelledby="tab6" tabindex="0" >
      <h1 class="text-center" >6</h1>
    </div>
  </div>

  </div>
</div>
  
</div>
!

CSS
!

JS 

              
                window.onresize = function(event) {
    CheckTabSize();
};

$('.nav-tabs li').click(function() {
    setTimeout(SetActiveTabsYourself, 10);
});

var ShownTabs = '.nav-tabs .nav-item[style!="display: none;"]';
var HiddenTabs = '.nav-tabs .nav-item[style*="display: none;"]';
function CheckTabSize() {
      //Get Tab Area
    var buttonWidth = $('#nav-buttons').width();
    var tabAreaWidth = $('.nav-tabs').width() - buttonWidth;
    var tabWidths = 0;
    var firstHidden;
  
    //Add Up the Tabs' Widths
    $.each($(ShownTabs), function(idx, obj){
      tabWidths += $(obj).outerWidth(); //padding
    });
  
    //Find out which ones to hide
    while(tabWidths > tabAreaWidth) {
      var hider = $(ShownTabs).last();
      tabWidths -= $(hider).outerWidth();
      $(hider).hide();
    }
  
    //See if we can show any
    firstHidden = $(HiddenTabs).first();
    while(firstHidden.length > 0 && (tabWidths + firstHidden.width()) < tabAreaWidth) {
      tabWidths += $(firstHidden).outerWidth();
      $(firstHidden).show();
      firstHidden = $(HiddenTabs).first();
    }
  
    //Affect drop-down button
    if ($(HiddenTabs).length === 0) {
      $('#tabDrop').hide();
    } else {
      $('#tabDrop').show();
    }
  
    //Hide drop-down tabs as necessary
    var shown = $(ShownTabs);
  
    $.each($('#tabDropdown li'), function(idx, obj){
        var isInShown = $.grep(shown, function(el){ return $(el).find('a').data('bs-target') == $(obj).find('a').data('bs-target'); }).length > 0;
        if (isInShown) {
            $(obj).hide();
        } else {
            $(obj).show();
        }
    });
}
function SetActiveTabsYourself() {    
    $('.nav-tabs li').removeClass('active');
    var activeTab = $('.tab-pane .active');
    if (activeTab.length > 0) {
        var activeID = $(activeTab[0]).attr('id');
        $('.nav-tabs li a[data-bs-target=#' + activeID + ']').parent().addClass('active');
    }
}

setTimeout(CheckTabSize, 100);
setTimeout(SetActiveTabsYourself, 100);
!
999px

Console