btbtt.css

@-webkit-keyframes spinner-border {
    to {
      transform: rotate(360deg) /* rtl:ignore */;
    }
  }
  
  @keyframes spinner-border {
    to {
      transform: rotate(360deg) /* rtl:ignore */;
    }
  }
.spinner-border {
    display: inline-block;
    width: 2rem;
    height: 2rem;
    vertical-align: -0.125em;
    border: 0.25em solid currentColor;
    border-right-color: transparent;
    border-radius: 50%;
    -webkit-animation: 0.75s linear infinite spinner-border;
    animation: 0.75s linear infinite spinner-border;
  }
  .spinner-border-sm {
    width: 1rem;
    height: 1rem;
    border-width: 0.2em;
  }
  .mouse-on {
    cursor: pointer;
  }