PDF 转 EPUB
把 PDF 重新排版成 EPUB，文字能在电子阅读器和手机上自动适配大小，不用再靠手动缩放看清楚。
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The universal document format. Looks the same on every device — the standard for documents that must not change.
EPUB
The open ebook standard used by most readers and stores. Text reflows to fit any screen size.