How do I remove white space under the full page image.

[piyarad27]

Hello Calibre I try to convert image from epub to pdf using <style>@page {margin: 0pt; padding: 0;} </style> on head and on the body I have <dir> class="full-page-strech". And I try to resize the page in output during convert book but whe I take a closer look at the bottom of the page there are a small white line under the image I also try many resize but nothing work what should I do? here is the image when I zoom in the image in the pdf file