In CSS, the adjoining margins of two or more boxes (which might or might not be siblings) can combine to form a single margin.

css中，两个或更多的盒子(可以但不一定是兄弟元素)相邻的(垂直)外边距可以合并成一个外边距。

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In CSS, the adjoining margins of two or more boxes (which might or might not be siblings) can combine to form a single margin.

在css中，两个或者更多(有可能是同辈或者是后辈)毗邻盒子的外边距会重叠形成一个单一的边距。

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More than two thirds of stakeholder pension schemes remain "empty boxes" without a single contribution or scheme member.

BBC: Analysis