body {background-image:url("keisanback.gif")}
  p  {font-sizelarge; color:black; 
       margin: 10px 10px; float:left;  
      }

  .soro{   width:550px; padding:10px;
           border:10px double #660000;
           position:relative; top100px;left:20px;
          background-color:brown;
          white-space: nowrap;
		 }
 <!-- form {clear : left;}-->
  .way_hide{display:none;}
  .way_shown{margin: 10px 30px; float:left; }
  .way_on{ width:280px;height:20px;padding:10px; 
       background-color:red }

  .way_out{ width:280px;height:20px;padding:10px;
       background-color:white}  
  .hide {display:none}
  .on { position:absolute;}
  .kukuichiran {width:350px; padding:5px; margin-left:50px; margin-right:10px;
				font-size:13pt;
                float:left;}
  
  .tejyun {  width:500px; padding:10px;
             font-size:13pt;} 
  .shown{display:visibility}
  .hide{display:none;} 
  .btn{width: 100px; height:40px; font-size:15pt;}  
#mainbox{margin-left:10px; float:left; font-size:15pt;}/*全体を左に、割り九九の位置を調整*/
#pageback{clear : left;} /*戻るの部分でフロート解除*/
#setnum{width:150px; height:50px; font-size:20pt;}
#speed_change{width:150px;font-size:15pt;}


@madia screen and (min-width:1000px){
#space_bfkuku{clear : left;} /*九九の前のスペースでフロート解除*/
#mainbox{margin-left:10px; float:left; font-size:30pt;}/*全体を左に、割り九九の位置を調整*/
  .kukuichiran {width:350px; padding:5px; margin-left:50px; margin-right:10px;
				font-size:30pt;
                float:left;}
  
  .tejyun {  width:500px; padding:10px;
             font-size:30pt;} 
 
}