gitlab-board-style.css

.boards-app > div {
    display: flex !important;
}

.board {
    margin: 0 0 0 0 !important;
    padding: 0 !important;
}

.board-list-component > .board-list {
    overflow: auto !important;
}

.board-list-component {
    overflow: inherit !important;   
}

.card {
    display: block !important;
    padding: 2px !important;
}

.card-title {
    font-size: 85% !important;
}


.card-footer > .label {
    padding: 3px !important;
    border-radius: 2px !important;
    font-size: 75% !important;
    margin-right: 2px !important;
    font-weight: bold !important;
}

.board-inner {
  border-radius: 0;
  border: none;
  border-right: 1px solid #ccc;
}

.board-header.has-border {
    border-top-left-radius: 0;
    border-top-right-radius: 0;
}