内层div的margin-top影响外层div——引出外边距合并Collapsing margins作者：zccst今天才算是了解边距合并。正如一位前辈所言，每一个CSS的坑，都让你学到不少知识。 /*出现原因是符合垂直边距合并的条件。(No.6)The top margin of an in-flow block element collapses with its first in-flow block-level child's top margin if the element has no top border, no top padding, and the child h Read More