body {
  background-color: #2E0A3C;
  background-image: url("../fondo.png");
  background-position: center center;
  background-attachment: fixed;
  background-size: cover;
  background-repeat: no-repeat;
  padding-top: 100px;
}

.container {
  width: 400px;
  margin: 0 auto;
  background: #E4D8B4;
  border-radius: 8px;
  border-bottom: 15px solid rgba(0, 0, 0, 0.3);
  padding: 30px;
  text-align: center;
  box-shadow: inset 0 1px 5px 5px rgba(0, 0, 0, 0.2);
}

#display {
  display: block;
  height: 100px;
  border: 15px inset #aaa;
  background: #333;
  margin-bottom: 25px;
  color: rgba(255, 255, 255, 0.4);
  letter-spacing: 1px;
  text-align: right;
  padding: 0 30px;
  line-height: 2;
  font-size: 3em;
  font-family: "LCD";
}

button {
  cursor: pointer;
  background: linear-gradient(#83B799, #729e84);
  border-top-left-radius: 4px;
  border-top-right-radius: 4px;
  border-bottom-left-radius: 2px;
  border-bottom-right-radius: 2px;
  border-right: 1px solid #4d6b5a;
  border-left: 1px solid #4d6b5a;
  border-bottom: 9px solid #4d6b5a;
  border-top: 1px solid #4d6b5a;
  padding: 18px 30px;
  color: #fff;
  font-weight: bold;
  position: relative;
  box-shadow: 0 2px 1px 2px rgba(0, 0, 0, 0.6), inset 0 0 3px 4px rgba(0, 0, 0, 0.075);
  font-size: 1.2em;
  display: inline-block;
}

button:active {
  background: linear-gradient(#729e84, #83B799);
  border-top: 1px solid #4d6b5a;
  border-bottom: 3px solid #4d6b5a;
  margin-top: 3px;
  box-shadow: 0 1px 1px 2px rgba(0, 0, 0, 0.6), inset 0 0 3px 4px rgba(0, 0, 0, 0.05);
}

button.red:active {
  background: linear-gradient(#B35550, #E86F68);
  border-top: 1px solid #B35550;
  border-bottom: 3px solid #B35550;
}

button.gray:active {
  background: linear-gradient(#7F7F7F, #999);
  border-top: 1px solid #777;
  border-bottom: 3px solid #666;
}

button:focus {
  outline: none;
}

.red {
  background: linear-gradient(#994945, #E86F68);
  color: #fff;
  border-color: #994945;
}

.gray {
  background: linear-gradient(#999, #7F7F7F);
  color: #333;
  border-color: #666;
}

#calculator {
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-template-rows: repeat(5, minmax(80px, auto));
  grid-gap: 12px 15px;
}
#calculator button:active {
  height: calc(100% - 2px);
}
#calculator .span-h {
  grid-column: span 2;
}
#calculator .span-v {
  grid-row: span 2;
}

.control {
  text-align: right;
}

.brand {
  font-family: "Impact", sans-serif;
  float: left;
  font-size: 1.8em;
  line-height: 1;
  text-shadow: -1px -1px 0px rgba(255, 255, 255, 0.3), 1px 1px 0px rgba(0, 0, 0, 0.8);
  color: #222;
  opacity: 0.7;
}

.switch {
  position: relative;
  display: inline-block;
  width: 60px;
  height: 34px;
  margin-bottom: 20px;
}
.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #ccc;
  -webkit-transition: 0.4s;
  transition: 0.4s;
}
.slider:before {
  position: absolute;
  content: "";
  height: 26px;
  width: 26px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  -webkit-transition: 0.4s;
  transition: 0.4s;
}

input:checked + .slider {
  background-color: #2196F3;
}
input:focus + .slider {
  box-shadow: 0 0 1px #2196F3;
}
input:checked + .slider:before {
  -webkit-transform: translateX(26px);
  -ms-transform: translateX(26px);
  transform: translateX(26px);
}