@media screen and (min-width:768px) and ( max-width:1025px) {

    .box1 {
        display: inline-block;
        width: 200px;
        height: 400px;
        margin: 0px 0px 0px -300px;
        background: #4b4b4b;
        text-align:center;
        animation: box11 25s linear;
        animation-fill-mode: forwards;
       }
       @keyframes box11 {
        0% { transform:translate( 350px , -350px) skewX(-45deg) ;}
      100% { transform:translate( -550px , 550px) skewX(-45deg);}
       }

       .box2 {
        display: inline-block;
        width: 200px;
        height: 100px;
        margin: 0px 0px 0px -345px;
        background: #4b4b4b;
        text-align:center;
        animation: box22 28s infinite linear;
       }
       @keyframes box22 {
        0% { transform:translate( 900px , -900px) skewX(-45deg) ;}
      100% { transform:translate( -100px , 100px) skewX(-45deg);}
       }

       .box3 {
        display: inline-block;
        width: 200px;
        height: 400px;
        margin: 0px 0px 0px -45px;
        background: #4b4b4b;
        text-align:center;
        animation: box33 35s infinite linear;
       }
       @keyframes box33 {
        0% { transform:translate( 1300px , -1300px) skewX(-45deg) ;}
      100% { transform:translate( -150px , 150px) skewX(-45deg);}
       }
       /*1行目終わり*/

       .box4 {
        display: inline-block;
        width: 200px;
        height: 300px;
        margin: 0px 0px 0px 150px;
        background: #4b4b4b;
        text-align:center;
        animation: box44 20s linear;
        animation-fill-mode: forwards;
       }
       @keyframes box44 {
        0% { transform:translate( 50px , -50px) skewX(-45deg) ;}
      100% { transform:translate( -500px , 500px) skewX(-45deg);}
       }

       .box5 {
        display: inline-block;
        width: 200px;
        height: 300px;
        margin: 0px 0px 0px -200px;
        background: #4b4b4b;
        text-align:center;
        animation: box55 32s linear;
        animation-fill-mode: forwards;
       }
       @keyframes box55 {
        0% { transform:translate( 600px , -600px) skewX(-45deg) ;}
      100% { transform:translate( -500px , 500px) skewX(-45deg);}
       }

       .box6 {
        display: inline-block;
        width: 200px;
        height: 300px;
        margin: 0px 0px 0px -200px;
        background: #4b4b4b;
        text-align:center;
        animation: box66 68s infinite linear;
       }
       @keyframes box66 {
        0% { transform:translate( 1100px , -1100px) skewX(-45deg) ;}
      100% { transform:translate( -800px , 800px) skewX(-45deg);}
       }

       .box7 {
        display: inline-block;
        width: 200px;
        height: 300px;
        margin: 0px 0px 0px -200px;
        background: #4b4b4b;
        text-align:center;
        animation: box77 72s infinite linear;
       }
       @keyframes box77 {
        0% { transform:translate( 1650px , -1650px) skewX(-45deg) ;}
      100% { transform:translate( -500px , 500px) skewX(-45deg);}
       }
       /*2行目終わり*/

       .box8 {
        display: inline-block;
        width: 200px;
        height: 700px;
        margin: 0px 0px 0px 400px;
        background: #4b4b4b;
        text-align:center;
        animation: box88 15s linear;
        animation-fill-mode: forwards;
       }
       @keyframes box88 {
        0% { transform:translate( -400px , 400px) skewX(-45deg) ;}
      100% { transform:translate( -1400px , 1400px) skewX(-45deg);}
       }

       .box9 {
        display: inline-block;
        width: 200px;
        height: 700px;
        margin: 0px 0px 0px -560px;
        background: #4b4b4b;
        text-align:center;
        animation: box99 29s infinite linear;
       }
       @keyframes box99 {
        0% { transform:translate( 1400px , -1400px) skewX(-45deg) ;}
      100% { transform:translate( -1000px , 1000px) skewX(-45deg);}
       }
       /*3行目終わり*/

       .box10 {
        display: inline-block;
        width: 200px;
        height: 100px;
        margin: 0px 0px 0px 0px;
        background: #4b4b4b;
        text-align:center;
        animation: box100 20s infinite linear;
       }
       @keyframes box100 {
        0% { transform:translate( 600px , -600px) skewX(-45deg) ;}
      100% { transform:translate( -1000px , 1000px) skewX(-45deg);}
       }
       
       .box11 {
        display: inline-block;
        width: 200px;
        height: 100px;
        margin: 0px 0px 0px -200px;
        background: #4b4b4b;
        text-align:center;
        animation: box110 29s infinite linear;
       }
       @keyframes box110 {
        0% { transform:translate( 1100px , -1100px) skewX(-45deg) ;}
      100% { transform:translate( -1000px , 1000px) skewX(-45deg);}
       }
       /*4行目終わり*/

       .box12 {
        display: inline-block;
        width: 200px;
        height: 400px;
        margin: 0px 0px 0px 0px;
        background: #4b4b4b;
        text-align:center;
        animation: box120 18s linear;
        animation-fill-mode: forwards;
       }
       @keyframes box120 {
        0% { transform:translate( -100px , 100px) skewX(-45deg) ;}
      100% { transform:translate( 500px , -500px) skewX(-45deg);}
       }

       .box13 {
        display: inline-block;
        width: 200px;
        height: 400px;
        margin: 0px 0px 0px -200px;
        background: #4b4b4b;
        text-align:center;
        animation: box130 30s infinite linear;
       }
       @keyframes box130 {
        0% { transform:translate( -900px , 900px) skewX(-45deg) ;}
      100% { transform:translate( 500px , -500px) skewX(-45deg);}
       }
       .box14 {
        display: inline-block;
        width: 200px;
        height: 200px;
        margin: 0px 0px 0px 200px;
        background: #4b4b4b;
        text-align:center;
        animation: box140 20s infinite linear;
       }
       @keyframes box140 {
        0% { transform:translate( 300px , -300px) skewX(-45deg) ;}
      100% { transform:translate( -1000px , 1000px) skewX(-45deg);}
       }

       .box15 {
        display: inline-block;
        width: 0px;
        height: 0px;
        margin: 0px 0px 0px -100px;
        background: #4b4b4b;
        text-align:center;
        animation: box150 20s infinite linear;
       }
       @keyframes box150 {
        0% { transform:translate( 600px , -600px) skewX(-45deg) ;}
      100% { transform:translate( -300px , 300px) skewX(-45deg);}
       }

}