style.css

#header {
  width: 100%;
  height: 10%;
  border: 2px solid black;
  text-align: center;
  vertical-align: middle;

  top: 0;
  right: 0;
  left: 0;
  position: fixed;
}

#body {
  display: flex;
  justify-content: space-around;
  width: 100%;
  margin-top: 12%;
}

.grid {
  display: grid;
  grid-template-columns: auto auto auto;
}

.nonet {
  display: grid;
  grid-template-columns: auto auto auto;
  /* background-color: rgb(35, 35, 35); */
  /* padding: 5px; */
  width: 150px;
  height: 150px;
}

.box {
  border:none;
  background-color:rgba(0,0,0,0);
  width: 94%;
  height: 94%;
  text-align: center;
  font-size: 2rem;
}
.highlight {
  background-color: rgba(4, 183, 207, 0.3);
}

#run {
  margin-top: 10%;
}
#import-button {
  margin-top: 10%;
}
#clear-grid {
  margin-top: 10%;
}

/* input:read-only {
  background-color: red;
} */

#canvas {
  position:absolute;
  z-index: -1;
}

/* #canvas-grid {
  display:grid;

} */

/* Loading screen */

#loading {
  position:fixed;
  top: 0px;
  left:0px;
  width: 100%;
  height: 100%;
  margin-left: 0px;
  margin-right: 0px;
  padding: 0px;
  text-align: center;
  background-color: rgba(70, 70, 70, 0.8);
  display:flex;
  justify-content: center;
  display:none;
}

.vertical-center {
  margin: 0;
  position: absolute;
  top: 50%;
  background-color: #ababab;
  padding: 10px, 0px;
  vertical-align: middle;
}

::placeholder {
  color: peru;
  opacity: 1; /* Firefox */
}

/* Taken from https://loading.io/css/ with CC0 liscence */

.lds-ring {
  display: inline-block;
  position: relative;
  width: 80px;
  height: 80px;
  vertical-align: middle;
}
.lds-ring div {
  box-sizing: border-box;
  display: block;
  position: absolute;
  width: 64px;
  height: 64px;
  margin: 8px;
  border: 8px solid #fff;
  border-radius: 50%;
  animation: lds-ring 1.2s cubic-bezier(0.5, 0, 0.5, 1) infinite;
  border-color: #fff transparent transparent transparent;
}
.lds-ring div:nth-child(1) {
  animation-delay: -0.45s;
}
.lds-ring div:nth-child(2) {
  animation-delay: -0.3s;
}
.lds-ring div:nth-child(3) {
  animation-delay: -0.15s;
}
@keyframes lds-ring {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

/* End loading screen */