styles.qss

QPushButton {
    background-color: #0d6efd;
    color: #fff;
    font-weight: 600;
    border-radius: 10px;
    border: 1px solid #0d6efd;
    padding: 5px 15px;
    margin-top: 10px;
    outline: 0px;
}

QToolTip {
    background-color: #8ad4ff;
    color: black;
    border: #8ad4ff solid 1px
}

QTableView {
    selection-background-color: #45BC68;
}

QTableCornerButton::section {
    background-color: rgb(58, 58, 58);
}