BEM. Positioning element, parent element?

Question

css

Is it normal according to BEM to set the positioning of an element, the parent element, through flex?

.header__menu{
      display: flex;
}
   .header__element-menu{
      padding: 0 30px;
      display: flex;
      align-items: center;
}

<div class="header">
        <nav class="header__menu">
            <a class="header__element-menu">Тренировки</a>
            <a class="header__element-menu">Питание</a>
            <a class="header__element-menu">Магазин</a>
        </nav>
</div>