Hardly distinguishable colors of literals and meta-variables

[sancho20021]

In Chromium web-browser it is difficult to distinguish which text is marked as literal, and which as (meta)-variable.
Example:
url: https://github.com/rust-lang/reference/edit/master/src/items/functions.md

Literals are colored light gray, but the background is light blue with low saturation. They are very similar, so it is difficult to see, for example, does this parenthesis relate to grammar (meta) language, or Rust itself.
Literals should have distinguishable property to make them noticeable.