Change the border color of bootstrap table-bordered

table.rs-table-bordered{
    border:1px solid #c00000;
    margin-top:20px;
  }
table.rs-table-bordered > thead > tr > th{
    border:1px solid #c00000;
}
table.rs-table-bordered > tbody > tr > td{
    border:1px solid #c00000;
}

<table class="table table-sm o_main_table rs-table-bordered">