function Menu(menu_id)
{
 switch(menu_id)
 {
  case 'sdevsubs':
   if (document.getElementById('scontacts').className == 'r-off')
    ContactsActiveOff();
   DevelopmentActiveOn();
   SeoActiveOff();
   SupportActiveOff();
  break;
  case 'sseosubs':
   if (document.getElementById('scontacts').className == 'r-off')
    ContactsActiveOff();
   DevelopmentActiveOff();
   SeoActiveOn();
   SupportActiveOff();
  break;
  case 'ssupsubs':
   if (document.getElementById('scontacts').className == 'r-off')
    ContactsActiveOff();
   DevelopmentActiveOff();
   SeoActiveOff();
   SupportActiveOn();
  break;
  case 'scontacts':
   ContactsActiveOn();
   DevelopmentActiveOff();
   SeoActiveOff();
   SupportActiveOff();
  break;
  case 'hide':
   DevelopmentActiveOff();
   SeoActiveOff();
   SupportActiveOff();
  break;
 }
}

function ContactsActiveOff()
{
 document.getElementById('scontacts').innerHTML = '<a href="#" OnClick="Menu(\'scontacts\');return false;">Контакты</a>';
 document.getElementById('scontacts').className = '';
}

function ContactsActiveOn()
{
 document.getElementById('scontacts').innerHTML = '<p>Контакты</p>';
 document.getElementById('scontacts').className = 'r-off';
}

function DevelopmentActiveOff()
{
 document.getElementById('sdev').innerHTML = '<a href="#" OnClick="Menu(\'sdevsubs\');return false;">Разработка сайтов</a>';
 document.getElementById('sdev').className = '';
 document.getElementById('sdevsubs').style.display = 'none';
}

function DevelopmentActiveOn()
{
 document.getElementById('sdev').innerHTML = '<p>Разработка сайтов</p>';
 document.getElementById('sdev').className = 'r-off';
 document.getElementById('sdevsubs').style.display = '';
}

function SeoActiveOff()
{
 document.getElementById('sseo').innerHTML = '<a href="#" OnClick="Menu(\'sseosubs\');return false;">Продвижение сайтов</a>';
 document.getElementById('sseo').className = '';
 document.getElementById('sseosubs').style.display = 'none';
}

function SeoActiveOn()
{
 document.getElementById('sseo').innerHTML = '<p>Продвижение сайтов</p>';
 document.getElementById('sseo').className = 'r-off';
 document.getElementById('sseosubs').style.display = '';
}

function SupportActiveOff()
{
 document.getElementById('ssup').innerHTML = '<a href="#" OnClick="Menu(\'ssupsubs\');return false;">Поддержка сайтов</a>';
 document.getElementById('ssup').className = '';
 document.getElementById('ssupsubs').style.display = 'none';
}

function SupportActiveOn()
{
 document.getElementById('ssup').innerHTML = '<p>Поддержка сайтов</p>';
 document.getElementById('ssup').className = 'r-off';
 document.getElementById('ssupsubs').style.display = '';
}