CSS Context Selector

Family: Fathers, fathers, siblings, sibling relationships

1. Ancestor elements: including the elements of multi-level descendants;

2. Parent element: An element that includes only one level of child elements;

3. Adjacent elements: An element that has the same parent;

1. Descendant selector: First find the ancestor element, then select all the specified descendant elements below it

Syntax: Between the ancestor and the target is separated by the space, can have the multilevel, uses the multiple space partition

Format: Ancestor target {declaration}

2. Sub-selector: Find the parent element first, and then select all the immediate descendant elements below him

Syntax: parent > Target element {style declaration}

3. Adjacent selector: First determines the starting point of the sibling element, selects all subsequent specified elements

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