$(document).ready(function() {
var dop = 146;
if ($.browser.mozilla || $.browser.opera) {
dop = 126;
}

 var blockheight = $(window).height() - ($('.header').height() + $('.menu').height() + $('.footer').height() + dop) ;
 if(blockheight < 344){
 blockheight = 344;
}
$('.content').height(blockheight);
});