body{/*ダイヤチェックの背景*/
background-size:23px 40px;
background-color:bisque;
background-image:
linear-gradient(-60deg,rgba(255,255,255,0.5) 25%, transparent 25%),
linear-gradient(60deg,rgba(255,255,255,0.5) 25%, transparent 25%),
linear-gradient(120deg,rgba(255,255,255,0.5) 25%, transparent 25%),
linear-gradient(-120deg,rgba(255,255,255,0.5) 25%, transparent 25%);
}