index.css

canvas {
  width: 100%;
  position: absolute;
  margin: auto;
  right: 0;
  left: 0;
  border: 1px solid #ebebeb; }

  @media screen and (max-height: 767px) and (orientation: landscape) {
    canvas {
      width: auto; }
  }

.navbar {
  padding-top: 0;
  padding-right: 1rem;
  padding-bottom: 0;
  padding-left: 1rem; }

.navbar-brand {
  padding-top: 0;
  font-size: 1.8rem; }

.border-bottom {
  border-bottom: 1px solid #ebebeb!important; }

.custom-control {
  min-height: 1.75rem; }

.firstRow {
  padding-top: .5rem; }

.row {
  padding-bottom: .35rem;
  padding-top: .35rem;
  border-bottom: 1px solid #ebebeb; }

.col-md-4, .col-auto {
  padding-bottom: .4rem;
  padding-top: .4rem; }

.h4 {
margin-bottom: .2rem; }

.no-padding {
  padding-bottom: 0rem;
  padding-top: 0rem;
  border: none; }

.custom-control-label:before {
  border: 1px solid #ced4da;
  background-color: transparent; }

.custom-control-label:focus {
  outline: none; }

.custom-checkbox .custom-control-input:checked~.custom-control-label::after {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 8 8'%3e%3cpath d='M6.564.75l-3.59 3.612-1.538-1.55L0 4.26 2.974 7.25 8 2.193z'/%3e%3c/svg%3e");
}

.custom-checkbox .custom-control-input:checked~.custom-control-label::before {
  border: 1px solid #007bff;
  background: transparent;
}
.custom-control-input:checked~.custom-control-label::before {
  border: 1px solid #007bff;
  background: transparent;
}

.custom-control-input:focus~.custom-control-label::before {
  box-shadow: none;
}

.container_show_var {
  visibility: none; }

/* The switch - the box around the slider */
.switch {
  position: relative;
  display: inline-block;
  width: 3rem;
  height: 1.5rem;
  margin-left: .5rem;
  margin-bottom: 0;
}

/* Hide default HTML checkbox */
.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

/* The slider */
.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  box-shadow: 0 0 0px 1px #ced4da;
  -webkit-transition: .4s;
  transition: .4s;
}

.slider:before {
  position: absolute;
  content: "";
  height: 1.2rem;
  width: 1.2rem;
  left: 0.15rem;
  bottom: 0.15rem;
  background: #ced4da;
  -webkit-transition: .4s;
  transition: .4s;
}

input:checked + .slider:before {
  -webkit-transform: translateX(1.5rem);
  -ms-transform: translateX(1.5rem);
  transform: translateX(1.5rem);
  background: #007bff;
}

  /* Rounded sliders */
.slider.round {
  border-radius: 1rem;
}

.slider.round:before {
  border-radius: 50%;
}