There does seem to be a tiny bit of unused space below the bottom row of keys but this seems to be necessary to permit the slider to merge into the main body.

底部按键下方有一段无用区域，这是将滑动块融入机身所必需的。

youdao

The preface begins, "Heaven was once broken and when it was mended, a bit was left unused, and this became the famous jade of Chia Pao Yü."

小说的引子写道：很久以前，天破了一个大口，（女娲）修补（缺口）时，剩下一小块（石头），于是成了贾宝玉的那块名玉。

youdao

The preface begins, "Heaven was once broken and when it was mended, a bit was left unused, and this became the famous jade of Chia Pao Yü."

小说的引子写道：很久以前，天破了一个大口，（女娲）修补（缺口）时，剩下一小块（石头），于是成了贾宝玉的那块名玉。

youdao