How can I remove the black thin border on my mobile view image?

[DSS5]

hi guys, can you help me to get rid of this(highlighted) black thin border in image(only visible in mobile view). i tried all i can think but not getting result. why this thin border is there and how can i remove this? please see screen shot. thanks 

[RockTechnolabs]

Hi @DSS5 Please share your store URL so I can check and help you out.

[RockTechnolabs · Accepted solution]

Hi @DSS5 Please add this CSS code in theme.liquid file above </body> tag

<style>
.card__inner {
    background: transparent;
}
</style>