calendar

hi all
i have a problem with calendar ,(or any other component i add)
the calendar is hidden and appears by click (from code)
the problem is that when the the calendar opens..the other components "jump"
is there any way to open the calendar without moving the calendar (like calendar in the outlook..)
here is the aspx:









test







and here is the code that of button click

protected void buttom_click(object sender, EventArgs e)
{
Cal.Visible = true;

}

thanks

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