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HTML 

              
                    <table class="desktop">
      <thead>
      <tr>
        <th>First Name</th>
        <th>Last Name</th>
        <th>Job Title</th>
      </tr>
      </thead>
      <tbody>
      <tr>
        <td>James</td>
        <td>Matman</td>
        <td>Chief Sandwich Eater</td>
      </tr>
      <tr>
        <td>The</td>
        <td>Tick</td>
        <td>Crimefighter Sorta</td>
      </tr>
      </tbody>
    </table>

    <table class="desktop">
      <thead>
      <tr>
        <th>First Name</th>
        <th>Last Name</th>
        <th>Job Title</th>
        <th>Favorite Color</th>
        <th>Wars or Trek?</th>
        <th>Porn Name</th>
        <th>Date of Birth</th>
        <th>Dream Vacation City</th>
        <th>GPA</th>
        <th>Arbitrary Data</th>
      </tr>
      </thead>
      <tbody>
      <tr>
        <td>James</td>
        <td>Matman</td>
        <td>Chief Sandwich Eater</td>
        <td>Lettuce Green</td>
        <td>Trek</td>
        <td>Digby Green</td>
        <td>January 13, 1979</td>
        <td>Gotham City</td>
        <td>3.1</td>
        <td>RBX-12</td>
      </tr>
      <tr>
        <td>The</td>
        <td>Tick</td>
        <td>Crimefighter Sorta</td>
        <td>Blue</td>
        <td>Wars</td>
        <td>John Smith</td>
        <td>July 19, 1968</td>
        <td>Athens</td>
        <td>N/A</td>
        <td>Edlund, Ben (July 1996).</td>
      </tr>
      <tr>
        <td>Jokey</td>
        <td>Smurf</td>
        <td>Giving Exploding Presents</td>
        <td>Smurflow</td>
        <td>Smurf</td>
        <td>Smurflane Smurfmutt</td>
        <td>Smurfuary Smurfteenth, 1945</td>
        <td>New Smurf City</td>
        <td>4.Smurf</td>
        <td>One</td>
      </tr>
      <tr>
        <td>Cindy</td>
        <td>Beyler</td>
        <td>Sales Representative</td>
        <td>Red</td>
        <td>Wars</td>
        <td>Lori Quivey</td>
        <td>July 5, 1956</td>
        <td>Paris</td>
        <td>3.4</td>
        <td>3451</td>
      </tr>
      <tr>
        <td>Captain</td>
        <td>Cool</td>
        <td>Tree Crusher</td>
        <td>Blue</td>
        <td>Wars</td>
        <td>Steve 42nd</td>
        <td>December 13, 1982</td>
        <td>Las Vegas</td>
        <td>1.9</td>
        <td>Under the couch</td>
      </tr>
      </tbody>
    </table>
!

CSS 

              
                @import "compass/css3";

table {
  margin: 50px; 
  td, th {
    padding: 10px;
    text-align: left;
  }
}

.desktop {
  tbody tr:nth-child(odd) {
    background: #eee;
  }
}

.generated_for_mobile tr.odd {
  background: #eee;
}
!

JS 

              
                $('table').each(function() {
  var table = $(this); // cache table object
  var head = table.find('thead th');
  var rows = table.find('tbody tr').clone(); // appending afterwards does not break original table

  // create new table
  var newtable = $(
    '<table class="generated_for_mobile">' +
    '  <tbody>' +
    '  </tbody>' +
    '</table>'
  );

  // cache tbody where we'll be adding data
  var newtable_tbody = newtable.find('tbody');

  rows.each(function(i) {
    var cols = $(this).find('td');
    var classname = i % 2 ? 'even' : 'odd';
    cols.each(function(k) {
      var new_tr = $('<tr class="' + classname + '"></tr>').appendTo(newtable_tbody);
      new_tr.append(head.clone().get(k));
      new_tr.append($(this));
    });
  });

  $(this).after(newtable);
});
!
999px

Console