How to decode base64 for both Linux and macOS?

On Linux I can do:

echo ${ANDROID_KEYSTORE} | base64 -di > android/keystores/staging.keystore

But on macOS, the same commands give:

base64: option requires an argument -- i
Usage:	base64 [-hvDd] [-b num] [-i in_file] [-o out_file]
  -h, --help     display this message
  -Dd, --decode   decodes input
  -b, --break    break encoded string into num character lines
  -i, --input    input file (default: "-" for stdin)
  -o, --output   output file (default: "-" for stdout)

I have tried to replace -di with --decode --input, but it didn't help. 1. How do I fix the macOS command? 2. Is there a command that works both on Linux (Debian/Ubuntu) and macOS?