In your case, it’s the best to use rotate option from transform property as mentioned before. There is also
writing-mode property and it works like rotate(90deg) so in your case, it should be rotated after it’s applied. Even it’s not the right solution in this case but you should be aware of this property.
More about transform: https://kolosek.com/css-transform/
More about writing-mode: https://css-tricks.com/almanac/properties/w/writing-mode/