.ba {
  border-style: solid;
  border-width: 1px;
}
.bt {
  border-top-style: solid;
  border-top-width: 1px;
}
.br {
  border-right-style: solid;
  border-right-width: 1px;
}
.bb {
  border-bottom-style: solid;
  border-bottom-width: 1px;
}
.bl {
  border-left-style: solid;
  border-left-width: 1px;
}
.bn {
  border-style: none;
  border-width: 0;
}

@media screen and (min-width: 30em) {
  .ba-ns {
    border-style: solid;
    border-width: 1px;
  }
  .bt-ns {
    border-top-style: solid;
    border-top-width: 1px;
  }
  .br-ns {
    border-right-style: solid;
    border-right-width: 1px;
  }
  .bb-ns {
    border-bottom-style: solid;
    border-bottom-width: 1px;
  }
  .bl-ns {
    border-left-style: solid;
    border-left-width: 1px;
  }
  .bn-ns {
    border-style: none;
    border-width: 0;
  }
}

@media screen and (min-width: 30em) and (max-width: 60em) {
  .ba-m {
    border-style: solid;
    border-width: 1px;
  }
  .bt-m {
    border-top-style: solid;
    border-top-width: 1px;
  }
  .br-m {
    border-right-style: solid;
    border-right-width: 1px;
  }
  .bb-m {
    border-bottom-style: solid;
    border-bottom-width: 1px;
  }
  .bl-m {
    border-left-style: solid;
    border-left-width: 1px;
  }
  .bn-m {
    border-style: none;
    border-width: 0;
  }
}

@media screen and (max-width: 60em) and (orientation: landscape) {
  .ba-ml {
    border-style: solid;
    border-width: 1px;
  }
  .bt-ml {
    border-top-style: solid;
    border-top-width: 1px;
  }
  .br-ml {
    border-right-style: solid;
    border-right-width: 1px;
  }
  .bb-ml {
    border-bottom-style: solid;
    border-bottom-width: 1px;
  }
  .bl-ml {
    border-left-style: solid;
    border-left-width: 1px;
  }
  .bn-ml {
    border-style: none;
    border-width: 0;
  }
}

@media screen and (min-width: 60em) {
  .ba-l {
    border-style: solid;
    border-width: 1px;
  }
  .bt-l {
    border-top-style: solid;
    border-top-width: 1px;
  }
  .br-l {
    border-right-style: solid;
    border-right-width: 1px;
  }
  .bb-l {
    border-bottom-style: solid;
    border-bottom-width: 1px;
  }
  .bl-l {
    border-left-style: solid;
    border-left-width: 1px;
  }
  .bn-l {
    border-style: none;
    border-width: 0;
  }
}