var nAct = 0;
var browserwidth = 0;
var browserheight = 0;
var minXY = 300;

//
var resizeTimer = null;
//

function resize() {
   //
   browserwidth = $(window).width();
   browserheight = $(window).height();
   //
   if ( (browserwidth>minXY) && (browserheight>minXY) ) {
     //
     var maxWidth = browserwidth-10;
     var maxHeight = browserheight-50;
     var ratio = 0;
     //
     ratio = maxWidth / width;
     height_new = height * ratio;

     if( height_new > maxHeight ) ratio = maxHeight / height;
     //
     width_new = width * ratio;
     //
     if (width_new>width) width_new = width; 
     //
     $("#main_img").css("width", width_new);
     $("#main_img").css("left", (maxWidth-width_new)/2 );
     $("#main_img").css("top", 10 );
     $("#main_img").css({"display":"block"});
     //
   }
 }

 $(window).resize(function(){
   browserwidth = $(window).width();
   browserheight = $(window).height();
   resize();
 });

$(document).ready(function(){
 //
  $(document).keydown(function(e) {
      switch(e.keyCode) { 
         case 39:
            $('#href_next_img').submit();
            break;
         case 37:
            $('#href_prev_img').submit();
            break;
      }
   });

});
 //