CSS: writing-mode
フロー方向
と
書字方向
を指定する
writing-mode: horizontal-tb
writing-mode: vertical-lr
https://developer.mozilla.org/ja/docs/Web/CSS/CSS_Flow_Layout/Flow_Layout_and_Writing_Modes
https://gyazo.com/148c181c8d153958f0c2ae68ed4f0795
/mrsekut-book-486246517X/020