Formato Bip39 Some words are shorter than four letters, like the word “act”. Other words are lengthier than four letters, for example “summary”. It is possible to see the entire source code in standalone, offline html file. Alternatively it is possible to check the individual css and js documents in https://mixbookmark.com/story4029401/bip39-mnemonic-to-seed-what-does-bip39-mean