.wp-block-table.is-style-fancy td {
	border: none;
	border-top: 1px solid #0076b3;
}

.wp-block-table.is-style-fancy th {
	border: none;
	border-bottom: 3px solid #0076b3;
}

.wp-block-table.is-style-fancy th:first-child, 
.wp-block-table.is-style-fancy td:first-child {
	border-right: 2px solid red;
}