simple dropdown question- can you help me make this move up and down,

simple dropdown question- can you help me make this move up and down,

Hi, I want to make a very simple drop down menu - that when you click it it slides down and stays like that and when you click it again it slides back up. here is the code I have so far

  2.   <style>
  3. .block { 
  4. position: fixed; 
  5. background:url('images/DD_BG.png') top left no-repeat;
  6. width:400px; 
  7. height:320px;
  8. top: -250px; 
  9. right: 30px;  
  10. }
  11. </style>

  2. <script>
  3. $("#NewView").click(function(){
  4.   $(".block").animate({"top": "+=250px"}, "slow");
  5. }
  6. );
  7. </script>

i know this is incredibly simple but I just have no idea how to get any further.