This is all you need to know.
- In a row if inline-block elements, all figures are relative to the total height of the tallest inline-block element (including margin and padding)
- From what I can tell, the most reliable properties are vertical-align: top, which does exactly what it says, align to the top the tallest inline-block element. The other one is pixel length. 0 px starts at the bottom of the inline-block element.