Hide the scrollbars and the box shadow in pinterest widget

Question

I tried

#pinterest-container [class$=_img] {
  display: block !important;
  box-shadow: none !important;
  border-radius: 0 !important;  
}

#pinterest-container [class$=_col] {
  padding: 0;
}

from this post Minimal Pinterest Widget with CSS and a couple other posts but the border (box-shadow) doesn't budge. What can i do? Would changing the color work.

Also I need help with hiding the scroll bar of the widget (but still be able to scroll) on all browsers.

I tried this but it removes all scroll bars from the embedded page. I just want to remove the scrollbars of the widget only.

html {
    overflow: scroll;
    overflow-x: hidden;
}
::-webkit-scrollbar {
    width: 0;  /* Remove scrollbar space */
    background: transparent;  /* Optional: just make scrollbar invisible */
}
/* Optional: show position indicator in red */
::-webkit-scrollbar-thumb {
    background: #FF0000;
}

I have limited knowledge on CSS so please help and thank you in advance.