html {
  font-size: 14px;
}

@media (min-width: 768px) {
  html {
    font-size: 16px;
  }
}

.btn:focus, .btn:active:focus, .btn-link.nav-link:focus, .form-control:focus, .form-check-input:focus {
  box-shadow: 0 0 0 0.1rem white, 0 0 0 0.25rem #258cfb;
}

html {
  position: relative;
  min-height: 100%;
}

body {
  margin-bottom: 60px;
}

html, body {
    width: 100%;
    height: 100%;
    padding:0px;
    margin: 0px;
}

header, header * {
    padding: 0px;
    margin: 0px;
}

.box {
    display: flex;
    flex-flow: column;
    height: 100%;
}

.box .row {
    border: 1px dotted grey;
}

.box .row.header {
    flex: 0 1 auto;
    /* The above is shorthand for:
    flex-grow: 0,
    flex-shrink: 1,
    flex-basis: auto
    */
}

.box .row.content {
    display: content;
}

.box .row.footer {
    flex: 0 1 40px;
}