body, html {
  height: 100%;
}
.bg {
  height: 50%;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}
.none {
  display:none;
}
#fondo {
  background:#000;
  opacity:0.35;
  position:absolute;
  z-index:1000000;
 margin: auto;   
 width:100%; 
 height:100%;
}
.centrar {
overflow: hidden;
position: absolute;
height: 200px;
width: 300px;
left: 50%;
top: 50%;
margin-top: -100px;
margin-left: -150px;
}
.footer {
  position: absolute;
  bottom: 0;
  width: 100%;
  height: 60px;
  line-height: 60px; 
  margin-bottom:100px;
}
.table-dark {
    color: #fff;
    background-color: #212529;
}
.table-dark, .table-dark>th, .table-dark>td {
    background-color: #c6c8ca;
}
.switch {
  position: relative;
  display: inline-block;
  width: 40px;
  height: 24px;
}
.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: .4s;
  transition: .4s;
}
.slider:before {
  position: absolute;
  content: "";
  height: 16px;
  width: 16px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  -webkit-transition: .4s;
  transition: .4s;
}
input:checked + .slider {
  background-color: #2196F3;
}
input:focus + .slider {
  box-shadow: 0 0 1px #2196F3;
}
input:checked + .slider:before {
  -webkit-transform: translateX(16px);
  -ms-transform: translateX(16px);
  transform: translateX(16px);
}
.slider.round {
  border-radius: 34px;
}
.slider.round:before {
  border-radius: 50%;
}