title: Aligning chart title with left side of numbers on the y axis
body: <p>I am trying to make an Altair theme that conforms with our internal guidelines. I found this excellent <a href="https://towardsdatascience.com/consistently-beautiful-visualizations-with-altair-themes-c7f9f889602" rel="nofollow noreferrer">article</a> that solved most of my issues. However, neither the article nor a search of the documentation has solved the problem of aligning the chart title with the left side of the numbers on the y axis.
  <a href="https://i.stack.imgur.com/2dMer.png" rel="nofollow noreferrer">See the dotted line in Urban institute's theme for visual explanation</a>.
  The problem is that I do not know the width of the longest number on the y axis. The solutions I have found just hard code an offset for the expected width of the number. However, I have to make a theme that automatically conforms to the standard in all cases.
  Hints to possible solutions are welcome. I will try them out and post results.</p>