body {
    position: relative;
    z-index: 0;
    background: url(../images/20260217105153182491.png);
    background-repeat: no-repeat;    /* 繰り返さない */
    background-position: center;     /* 中央に配置 */
    background-size: cover;          /* 要素の全体を覆うように拡大縮小 */
    background-attachment: fixed;
}

@media screen and (max-width:768px) {
  body {
  	background-position: top; 
  }
}