How to get toolbar height in SCSS

I have a div inside my ion-content that I want to be the full size of that content on every device. There is an ion-header=>toolbar->title->label above it. Right now I am setting it to calc(100vh - 45px) because that seems to look right but I am sure I should not have that hardcoded 45px. It could be that other OSes use different toolbar heights for example.
One solution Have thought of is that there maybe a SCSS variable that I can use in place of 45px. Is there such a thing? I can’t find it