function $(id) {
  return document.getElementById(id);
}

function toggle_featured_case(n) {
  var featured_case, i = 1;
  while(featured_case = $('featured-case-' + i)) {
    if(featured_case.id == 'featured-case-' + n) {
      featured_case.style.display = '';
      $('case-' + i).className = 'current-case';
    }
    else {
      featured_case.style.display = 'none';
      $('case-' + i).className = '';
    }
    i++;
  }
}