html {
  height:100%;
  width:0%;
}

body {
  margin:0;
}

.bg {
  animation:slide 3s ease-in-out infinite alternate;
  background-image: linear-gradient(-60deg, #3c3 50%, #09f 50%);
  bottom:0;
  left:-0%;
  opacity:.9;
  position:fixed;
  right:-50%;
  top:0;
  z-index:-1;
}

.bg2 {
  animation-direction:alternate-reverse;
  animation-duration:4s;
}

.bg3 {
  animation-duration:5s;
}

/*    responsivo  */

.content-cel 
{
  /*   style="width: 800px; height: 600px; padding: 10px;"  */
  
  width: 800px; 
  height: 600px; 
  padding: 10px;
  
  background-color:rgba(255,255,255,.8);
  border-radius:.25em;
  box-shadow:0 0 .25em rgba(0,0,0,.25);
  box-sizing:border-box;
  left:50%;
  padding:-50vmin;
  position:fixed;
  text-align:center;
  top:50%;
  transform:translate(-50%, -50%);
}

.image-logo {
  position: absolute;
  width:"150"; 
  height:"200";
    z-index: 2;
  }
  
  @media (max-width: 600px) {
      .content-cel {
        width: 100%; /* El div ocupa todo el ancho en pantallas pequeñas */
        background-color: lightgreen;
      }
    }
    

h1 {
  font-family:monospace;
}

@keyframes slide {
  0% {
    transform:translateX(-25%);
  }
  100% {
    transform:translateX(25%);
  }
}