关于固定表头 下拉框藏不起来的问题 那位高手帮解决下!
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  <HTML   >  <HEAD>  
  <STYLE   type=text/css>  
 .tScroll   { 
 	BORDER-RIGHT:   black   1px   solid;   BORDER-TOP:   black   1px   solid;   OVERFLOW-X:   hidden;   OVERFLOW:   scroll;   BORDER-LEFT:   black      
 1px   solid;   CURSOR:   default;   BORDER-BOTTOM:   black   1px   solid;   HEIGHT:   100px;   BACKGROUND-COLOR:   #ffffff 
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 TR.tableHead   { 
 	POSITION:   relative;   HEIGHT:   16px;   BACKGROUND-COLOR:   #a4b6d7;   TEXT-ALIGN:   left 
 } 
  </STYLE>  
  </HEAD>  
  <BODY      >  
  <DIV   class=tScroll   id=tC>  
  <TABLE   cellSpacing=0   cellPadding=0   border=1   width= "98% ">  
     <TR   class=tableHead   >  
              <TD      > haha </TD>  
              <TD   > haha </TD>  
              <TD   > haha </TD>  
              <TD   > haha </TD>  
              <TD   > haha </TD>  
        </TR>  
        <TR   >  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
        <TR   >  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD>  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           </TR>  
        <TR   >  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
           <TD   >  <SELECT   name=gd1>  <OPTION   value=haha   > haha </OPTION>  </SELECT>  </TD>  
     &n