body {
  background-color: #333;
}

.loading {
    position: relative;
    display: inline-block;
}

.loading::before{
    content: "";
    position: absolute;
    width: 100px;
    height: 100px;
    background-color: #1c5ba2;
    border-radius: 100%;
    z-index: 5;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    -webkit-animation: slide-top 0.5s ease-out infinite alternate ;
        animation: slide-top 0.5s ease-out infinite alternate ;
 }

 #c {
     position: relative;
     background-color: black;
 }

/* ----------------------------------------------
 * Generated by Animista on 2019-9-17 14:35:13
 * Licensed under FreeBSD License.
 * See http://animista.net/license for more info.
 * w: http://animista.net, t: @cssanimista
 * ---------------------------------------------- */

/**
 * ----------------------------------------
 * animation slide-top
 * ----------------------------------------
 */
 @-webkit-keyframes slide-top {
    0% {
      -webkit-transform: translate(-50%, 50%);
              transform: translate(-50%, 50%);
    }
    100% {
      -webkit-transform: translate(-50%, -150%);
              transform: translate(-50%, -150%);
    }
  }
  @keyframes slide-top {
    0% {
      -webkit-transform: translate(-50%, 50%);
              transform: translate(-50%, 50%);
    }
    100% {
      -webkit-transform: translate(-50%, -150%);
              transform: translate(-50%, -150%);
    }
  }


/**
 * ----------------------------------------
 * Copy from https://www.w3schools.com/howto/howto_js_rangeslider.asp
 * ----------------------------------------
 */
 .slidecontainer {
  width: 100%; /* Width of the outside container */
}

/* The slider itself */
.slider {
  -webkit-appearance: none;  /* Override default CSS styles */
  appearance: none;
  width: 100%; /* Full-width */
  height: 25px; /* Specified height */
  background: #d3d3d3; /* Grey background */
  outline: none; /* Remove outline */
  opacity: 0.7; /* Set transparency (for mouse-over effects on hover) */
  -webkit-transition: .2s; /* 0.2 seconds transition on hover */
  transition: opacity .2s;
}

/* Mouse-over effects */
.slider:hover {
  opacity: 1; /* Fully shown on mouse-over */
}

/* The slider handle (use -webkit- (Chrome, Opera, Safari, Edge) and -moz- (Firefox) to override default look) */
.slider::-webkit-slider-thumb {
  -webkit-appearance: none; /* Override default look */
  appearance: none;
  width: 25px; /* Set a specific slider handle width */
  height: 25px; /* Slider handle height */
  background: #4CAF50; /* Green background */
  cursor: pointer; /* Cursor on hover */
}

.slider::-moz-range-thumb {
  width: 25px; /* Set a specific slider handle width */
  height: 25px; /* Slider handle height */
  background: #4CAF50; /* Green background */
  cursor: pointer; /* Cursor on hover */
}