wona.github.com/js/application.js

// Your JavaScript
$(function() {
  $('.img-center-fill').load(function(){
    var parent = $(this).parent();
    var imgClass = (this.width/this.height > parent.width()/parent.height()) ? 'wide' : 'tall';
    $(this).addClass(imgClass);
  })

  /*
  var switchPos = $('#new-articles').position().top + $('#new-articles').height();

  $(window).scroll(function() {
    var scroll = $(window).scrollTop();
    if (scroll >= switchPos) {
      $(".navbar-wrapper").addClass("darken");

    } else {
      $(".navbar-wrapper").removeClass("darken");
    }
  });
  */

  ;(function($, window, document, undefined) {
    'use strict';

    var elSelector    = '.navbar-wrapper',
      elClassHidden = 'navbar--hidden',
      throttleTimeout = 250,
      $element    = $( elSelector  );

    if(!$element.length) return true;

    var $window     = $( window  ),
      wHeight     = 0,
      wScrollCurrent  = 0,
      wScrollBefore = 0,
      wScrollDiff   = 0,
      $document   = $( document  ),
      dHeight     = 0,

      throttle = function(delay, fn) {
      var last, deferTimer;
      return function() {
        var context = this, args = arguments, now = +new Date;
        if( last && now < last + delay  ) {
          clearTimeout( deferTimer  );
          deferTimer = setTimeout( function(){ last = now; fn.apply( context, args  );  }, delay  );

        }
        else {
          last = now;
          fn.apply( context, args  );
        }
      };
    };

    $window.on( 'scroll', throttle( throttleTimeout, function() {
      dHeight     = $document.height();
      wHeight     = $window.height();
      wScrollCurrent  = $window.scrollTop();
      wScrollDiff   = wScrollBefore - wScrollCurrent;

      if(wScrollCurrent <= 0) { // scrolled to the very top; element sticks to the top
        $element.removeClass(elClassHidden);
        $element.removeClass(elClassTop);
      }

      else if(wScrollDiff > 10 && $element.hasClass(elClassHidden)) // scrolled up; element slides in
        $element.removeClass( elClassHidden  );

      else if(wScrollDiff < -10) {// scrolled down
          if(wScrollCurrent + wHeight >= dHeight && $element.hasClass(elClassHidden)) // scrolled to the very bottom; element slides in
            $element.removeClass( elClassHidden  );

          else // scrolled down; element slides out
            $element.addClass( elClassHidden  );

        }

        wScrollBefore = wScrollCurrent;
    }));


  })( jQuery, window, document  );
});

function onYouTubeIframeAPIReady() {
  $('.youtube-video').each(function() {
    var id = $(this).data('id');

    var player = new YT.Player('youtube-video-' + id, {
      events: {
        'onStateChange': onPlayerStateChange
      }
    });

    function onPlayerStateChange(event) {
      if(event.data === YT.PlayerState.ENDED || event.data === YT.PlayerState.PAUSED)
        $('#youtube-title-' + id).show();
      else
        $('#youtube-title-' + id).hide();
    }

  });
}