anchor.diff:              }
           }
   
  +        function disableSummaryFields(){
  +            Element.update("summary-beginning", "Incorrect input")
  +            Element.update("summary-days", "")
  +            Element.update("summary-day-range", "")
  +        }
  +
           function highlightOdd(elt) {
               SC.highlight(elt, {
                   endcolor: "#eeeeee",
  
positive.code:             </div>
              <div class="row odd" id="summary">
                  <div class="label">Summary</div>
                  <div class="value">
                      The configured period will last for <span id="summary-days">1 day</span>
                      <span id="summary-day-range">(day 1)</span>.
              <span id="summary-repetitions">
                  It will have the same events on days <span id="summary-event-days"></span>.
              </span>
  
negative.code:                 numberOfDaysInUnit =1;
              }
              totalDays = reps * duration * numberOfDaysInUnit;
              if (isCorrectInput()) {
                  Element.update("summary-beginning", " The configured period will last for ")
                  Element.update("summary-days", totalDays + " day" + (totalDays != 1 ? "s" : ""))
                  highlightOdd("summary-days")
  
                  resetElement("periodError","");
                  if (duration > 1) {
                      Element.update("summary-day-range", "(" + startDay + " to " + (startDay + duration * numberOfDaysInUnit * reps - 1) + ")")
                  } else {
                      Element.update("summary-day-range", "(day " + startDay + ")")
                  }
              } else {
                  disableSummaryFields()
              }
              highlightOdd("summary-day-range")
  
              if (reps > 1 && duration >= 1 && isCorrectStartDay()) {
                  var sameDay = [startDay]
                  while (sameDay.length < reps) {
                      sameDay.push(sameDay.last() + duration * numberOfDaysInUnit)
  