# [K (ngn/k)], 16 bytes

    `c$97+26!+/-97+'

[Try it online!][ngn-38318bc6]

[K (ngn/k)]: https://codeberg.org/ngn/k
[ngn-38318bc6]: https://ngn.codeberg.page/k#eJxLs0pIVrE01zYyU9TW1wUy1Lm40qKVMlJzcvLL84tyUpRiQfzEpOSU1DQIOzk/JTU9PwfKKy5JTM5OrUjOSMxLT4UqBgGlWADA6Bwt

Explanation:

```
`c$97+26!+/-97+'  Main function. Takes implicit input
               '  For each character in the string
           -97+   + -97 to each of them to convert them into the 0..25 system
                  (In K, every character in a string is also an ASCII charcode)
         +/       Sum
      26!         Modulo by 26
   97+            + 97 to each of them (to convert them back to ASCII charcode)
`c$               And convert them back to characters
```