function showUnternehmen() { Element.hide('description_unternehmen'); Element.show('navigation_unternehmen'); }
function hideUnternehmen() { Element.show('description_unternehmen'); Element.hide('navigation_unternehmen'); }
function showPortfolio() { Element.hide('description_portfolio'); Element.show('navigation_portfolio'); }
function hidePortfolio() { Element.show('description_portfolio'); Element.hide('navigation_portfolio'); }
function showLabor() { Element.hide('description_labor'); Element.show('navigation_labor'); }
function hideLabor() { Element.show('description_labor'); Element.hide('navigation_labor'); }
function showJobs() { Element.hide('description_jobs'); Element.show('navigation_jobs'); }
function hideJobs() { Element.show('description_jobs'); Element.hide('navigation_jobs'); }