var sliderIntervalId = 0;
var sliderHeight = 298;
var sliding = false;
var slideSpeed = 10;

function Slide()
{
   if(sliding)
      return;
   sliding = true;
   if(sliderHeight == 298)
      sliderIntervalId = setInterval('SlideUpRun()', 30);
   else
      sliderIntervalId = setInterval('SlideDownRun()', 30);
}

function SlideUpRun()
{
   slider = document.getElementById('normalcontent');
   if(sliderHeight <= 0)
   {
      sliding = false;
      sliderHeight = 0;
      slider.style.height = '0px';
      clearInterval(sliderIntervalId);
   }
   else
   {
      sliderHeight -= slideSpeed;
      if(sliderHeight < 0)
         sliderHeight = 0;
      slider.style.height = sliderHeight + 'px';
   }
}

function SlideDownRun()
{
   slider = document.getElementById('normalcontent');
   if(sliderHeight >= 298)
   {
      sliding = false;
      sliderHeight = 298;
      slider.style.height = '298px';
      clearInterval(sliderIntervalId);
   }
   else
   {
      sliderHeight += slideSpeed;
      if(sliderHeight > 298)
         sliderHeight = 298;
      slider.style.height = sliderHeight + 'px';
   }
}