ワッフル生地
透過処理してあるので『#c96』(１箇所)をお好きな色にすれば色を変えられます。
【css】
body{/*ワッフル生地の背景*/
background-color:#c96;/*背景色*/
background-size: 20px 20px;
background-position:0 0,0 0,10px 10px,10px 10px;
background-image:
linear-gradient(45deg,rgba(0,0,0,.1) 18%,rgba(255,255,255,.2) 23%,rgba(255,255,255,.3) 25%,transparent 25%,transparent 75%,rgba(255,255,255,.3) 75%,rgba(255,255,255,.2) 77%,transparent 82%,transparent),
linear-gradient(-45deg,rgba(0,0,0,.1) 18%,rgba(255,255,255,.2) 23%,rgba(255,255,255,.3) 25%,transparent 25%,transparent 75%,rgba(255,255,255,.3) 75%,rgba(255,255,255,.2) 77%,transparent 82%,transparent),
linear-gradient(45deg,rgba(0,0,0,.1) 18%,rgba(255,255,255,.2) 23%,rgba(255,255,255,.3) 25%,transparent 25%,transparent 75%,rgba(255,255,255,.3) 75%,rgba(255,255,255,.2) 77%,transparent 82%,transparent),
linear-gradient(-45deg,rgba(0,0,0,.1) 18%,rgba(255,255,255,.2) 23%,rgba(255,255,255,.3) 25%,transparent 25%,transparent 75%,rgba(255,255,255,.3) 75%,rgba(255,255,255,.2) 77%,transparent 82%,transparent);
}
適宜必要なプロパティを追加してください