Hi, I'm Shamim Hossain
Answer some questions and I will help you to figure out the right CSS unit for your project.
Assuming you are only using these units for web development, not for print media.
em
The `em` unit, when used to declare font-size, will be relative it's ancestor's font-size.
For example, if you have a heading with a font-size of 3rem, and a span inside with a font-size of .5rem, the span will have a font-size of 1.5rem (3rem x .5).
For example, if you have a heading with a font-size of 3rem, and a span inside with a font-size of .5rem, the span will have a font-size of 1.5rem (3rem x .5).