怎么更改el-table-column的边框线

.el-table--border{
  border: 1px solid black;
}
.el-table td.el-table__cell, .el-table th.el-table__cell.is-leaf{
   border: 1px solid black;
}
.el-table--border::after, .el-table--group::after, .el-table::before{
   border:  black;
}