@media (min-width: 701px) {
  .app {
    display: block;
  }

  .rail,
  main {
    transition: width .22s ease, padding .22s ease, margin-left .22s ease;
  }

  .collapse {
    position: fixed;
    top: 50%;
    left: 231px;
    right: auto;
    z-index: 30;
    width: 28px;
    height: 74px;
    transform: translateY(-50%);
    transition: left .22s ease, border-color .15s ease, color .15s ease;
  }

  .rail.collapsed {
    width: 0;
    padding: 0;
    border-right: 0;
    background: transparent;
  }

  .rail.collapsed > :not(.collapse) {
    visibility: hidden;
    opacity: 0;
    pointer-events: none;
  }

  .rail.collapsed .collapse { left: 0; }
  .rail.collapsed ~ main { margin-left: 0; }
}