Vertical Text With CSS

.vericaltext{
writing-mode: vertical-lr;
text-orientation: upright;
}

.vertical {
  transform: rotate(90deg);
  transform-origin: left top 0;
  margin-left: 70px;
}

Пример – https://vahro.ru/other/menu-buttons-css-only/

The Easiest Way to Create Vertical Text With CSS – https://code.tutsplus.com/tutorials/the-easiest-way-to-create-vertical-text-with-css–net-15284