function image_top() {
dd = new Date();
mm = dd.getMonth()+1;
if ((mm == 3) || (mm == 4) || (mm == 5)) { s = 1; }
if ((mm == 6) || (mm == 7) || (mm == 8)) { s = 2; }
if ((mm == 9) || (mm == 10) || (mm == 11)) { s = 3; }
if ((mm == 12) || (mm == 1) || (mm == 2)) { s = 4; }
document.writeln("<img src=\"./d_parts/topimg"+s+".jpg\" alt=\"わかやま季節の風景\" width=\"759\" height=\"239\">");
}