onec.me/themes/beautifulhugo/static/css/codeblock.css

/* --- Code blocks --- */

.chroma .ln {
  margin-right: 0.8em;
  padding: 0 0.4em 0 0.4em;
}
pre code.hljs {
  padding: 9.5px;
}

.highlight tr, .highlight pre {
  border: none;
}

.highlight div:first-child {
  border-radius: 4px;
}

.highlight td:first-child pre, .highlight pre {
  border-top-left-radius: 4px;
  border-top-right-radius: unset;
  border-bottom-left-radius: 4px;
  border-bottom-right-radius: unset;
  overflow-y: hidden;
}

.highlight td:last-child pre, .highlight pre {
  border-radius: unset;
}

.highlight td:last-child pre code, .highlight pre code {
  white-space: pre;
}