What is the solar term when we are usually talking about cold?

During the Spring and Autumn Period, Jiexiu, a minister of Jin Wengong, took his mother to Mianshan to live in seclusion. Jin Wengong went to look for it himself, but he couldn't find it, so he had it set on fire and tried to burn him to death. As a result, Jie tui and his mother were burned to death. Jin Wengong was very sad, so he ordered that this day was not allowed to cook when it was hot, and later it became the Cold Food Festival. The location of Mianshan Mountain was later named Jiexiu, which is now Jiexiu City, Shanxi Province.

According to the ancient calendar, cold food is in the first three days of Qingming. But now they are all spent with Qingming. What the old man said about cold food is actually Qingming.