Simple HTML Table-formatting question

I would like to make the slider (the middle column) bigger (ideally about twice as big)

I changed the following line
<COLGROUP span="5" width="120"> to <COLGROUP span="7" width="120">
and the line

<TD  colspan="1"><div id="slider"></div></TD> to
<TD  colspan="3"><div id="slider"></div></TD>

But nothing changes!

What am I doing wrong?

Thanks!

<TABLE class="blocks">
						<COLGROUP span="5" width="120">
						<TR>	
							<TD></TD>
							<TD>Part One <INPUT TYPE="text" id="PER_1" value="100" onblur="javascript:updatePer2AndSlider()" class="Form30" label="Per1">%</TD>
							<TD  colspan="1"><div id="slider"></div></TD>
							<TD>Part Two <INPUT TYPE="text" id="PER_2" value="0" onblur="javascript:updatePer1AndSlider()"  class="Form30" label="Per2">%</TD>
							<TD></TD>
						</TR>	
						</TABLE>

Select allOpen in new window