首先，// 意味着从根元素开始选择所有的元素（与后面的选择器及条件匹配）而不论其嵌套的位置。

First, the // means to start at the root and select all elements (that match the selectors and criteria that follow), regardless of where they are nested.

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该选择器的每一位置必须能清晰识别，并且对应于单一操作或控制模式。

Each position of the selector must be clearly identifiable and must correspond to a single operating or control mode.

youdao

换档选择器(范围分)现在有UI支持基于位置的开关。

Gear shift selectors (range, split) now have UI support for position-based switches.

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