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// Find all YouTube videos
var $allVideos = $("iframe[src*='//www.youtube.com']"),
    // The element that is fluid width
    $fluidEl = $(".main-content");
// Figure out and save aspect ratio for each video
$allVideos.each(function() {
  $(this)
    .data('aspectRatio', this.height / this.width)
    // and remove the hard coded width/height
    .removeAttr('height')
    .removeAttr('width');
});
// When the window is resized
$(window).resize(function() {
  var newWidth = $fluidEl.width();
  // Resize all videos according to their own aspect ratio
  $allVideos.each(function() {
    var $el = $(this);
    $el
      .width(newWidth)
      .height(newWidth * $el.data('aspectRatio') * .89);
  });
// Kick off one resize to fix all videos on page load
}).resize();