Shadow DOM is a web component feature that lets you attach an isolated DOM subtree to any HTML element, hidden from the main document’s standard queries. A querySelector('audio') on the main document cannot see inside a Shadow Root unless you specifically traverse into it. If fermaw’s player was mounted inside a Shadow Root, basic DOM searches would come up empty.
思路：单调递增栈 + k 控制删除次数。高位越小整体越小，遇更小数字时弹出栈顶大数（仅当 k0）；栈空且当前为 0 则跳过（避免前导零）；若遍历完 k 仍0，从末尾再删 k 位。
，详情可参考51吃瓜
[&:first-child]:overflow-hidden [&:first-child]:max-h-full"。im钱包官方下载对此有专业解读
UPDATE: Solutions can be read here，更多细节参见同城约会