```python
def slug_word(word: str) -> str:
    """Lowercase a word and drop all non-alphanumeric characters."""
    return ''.join(char.lower() for char in word if char.isalnum())


def slug_make(phrase: str) -> str:
    """Join slugged words of a phrase with single hyphens."""
    return '-'.join(slug_word(word) for word in phrase.split())
```