少しも + [verb]ない 少しも + [i-adj 〜い → 〜く]ない 少しも + [na-adj] ではない/じゃない 少しも + [noun] ではない/じゃない
The pattern 少しも~ない is used to express "not at all" or "not even a little". It combines すこしも少しも (even a little) with a negative form of a verb or adjective to create a strong total negation – emphasizing that something is completely absent or that an action does not occur to any degree whatsoever.
少しも~ない carries a similar meaning to ぜんぜん全然〜~ない (not at all) and まったく全く〜~ない (not at all / absolutely not). However, 少しも literally means "not even a little", so it emphasizes that there is zero degree of something. It can sound slightly more emphatic or emotional than ぜんぜん全然.
This pattern is used in both casual and polite speech. In polite form, the negative ending simply becomes 〜~ません or 〜~ないです:
Note: すこしも少しも must always be paired with a negative form. Using it with an affirmative verb or adjective is ungrammatical.