var img1_on=new Image();
var img1_off=new Image();
var img2_on=new Image();
var img2_off=new Image();
var img3_on=new Image();
var img3_off=new Image();
var img4_on=new Image();
var img4_off=new Image();
var img5_on=new Image();
var img5_off=new Image();
var img6_on=new Image();
var img6_off=new Image();
var img7_on=new Image();
var img7_off=new Image();
var img11_on=new Image();
var img11_off=new Image();
img1_on.src="image/top/next_reikai_on.png";
img1_off.src="image/top/next_reikai_off.png";
img2_on.src="image/top/sub_movement.png";
img2_off.src="image/top/sub_movement_gray.png";
img3_on.src="image/top/sub_seisaku.png";
img3_off.src="image/top/sub_seisaku_gray.png";
img4_on.src="image/top/sub_yumekikin.png";
img4_off.src="image/top/sub_yumekikin_gray.png";
img5_on.src="image/top/sub_wellvoice.png";
img5_off.src="image/top/sub_wellvoice_gray.png";
img6_on.src="image/top/sub_ctb.png";
img6_off.src="image/top/sub_ctb_gray.png";
img7_on.src="image/top/sub_toronkai.png";
img7_off.src="image/top/sub_toronkai_gray.png";
img11_on.src="image/top/sub_academy.png";
img11_off.src="image/top/sub_academy_gray.png";

function rollon(targetimage) {
  if(targetimage=="image1") {
    document.images[targetimage].src=img1_on.src;
  }
  if(targetimage=="image2") {
    document.images[targetimage].src=img2_on.src;
  }
  if(targetimage=="image3") {
    document.images[targetimage].src=img3_on.src;
  }
  if(targetimage=="image4") {
    document.images[targetimage].src=img4_on.src;
  }
  if(targetimage=="image5") {
    document.images[targetimage].src=img5_on.src;
  }
  if(targetimage=="image6") {
    document.images[targetimage].src=img6_on.src;
  }
  if(targetimage=="image7") {
    document.images[targetimage].src=img7_on.src;
  }
  if(targetimage=="image11") {
    document.images[targetimage].src=img11_on.src;
  }
}

function rolloff(targetimage) {
  if(targetimage=="image1") {
    document.images[targetimage].src=img1_off.src;
  }
  if(targetimage=="image2") {
    document.images[targetimage].src=img2_off.src;
  }
  if(targetimage=="image3") {
    document.images[targetimage].src=img3_off.src;
  }
  if(targetimage=="image4") {
    document.images[targetimage].src=img4_off.src;
  }
  if(targetimage=="image5") {
    document.images[targetimage].src=img5_off.src;
  }
  if(targetimage=="image6") {
    document.images[targetimage].src=img6_off.src;
  }
  if(targetimage=="image7") {
    document.images[targetimage].src=img7_off.src;
  }
  if(targetimage=="image11") {
    document.images[targetimage].src=img11_off.src;
  }
}