function blocks_positioning()
{


	//получение координат нижней части блоков
	var block_left = window.parent.document.getElementById('left_column');
	var block_left_bottom_position = block_left.clientHeight + block_left.offsetTop;

	var block_center = window.parent.document.getElementById('center_column');
	var block_center_bottom_position = block_center.clientHeight + block_center.offsetTop;

	var block_right = window.parent.document.getElementById('right_column');
	var block_right_bottom_position = block_right.clientHeight + block_right.offsetTop;

	//определение самой большой позициии из определенных выше 
	var block_footer_offsetTop = 0;

	if (block_footer_offsetTop < block_left_bottom_position)
	{
		block_footer_offsetTop = block_left_bottom_position;
	}

	if (block_footer_offsetTop < block_center_bottom_position)
	{
		block_footer_offsetTop = block_center_bottom_position;
	}

	if (block_footer_offsetTop < block_right_bottom_position)
	{
		block_footer_offsetTop = block_right_bottom_position;
	}

	//передаю координаты блоку футера 
	var block_footer = document.getElementById('footer');
	block_footer.style.top = block_footer_offsetTop;

	//передаю координаты блоку банеров 
	var block_baners = document.getElementById('baners');
	block_baners.style.top = block_footer_offsetTop + 35;


}