`diff.less` file for language-diff Atom package. Place it at `~.atom/packages/language-diff/styles`

diff.less

@import "syntax-variables";
atom-text-editor {
  .syntax--diff {
    &.syntax--inserted &.syntax--inserted.syntax--punctuation {
      color: @syntax-color-added;
    }

    &.syntax--changed {
      color: @syntax-color-modified;
    }

    &.syntax--deleted &.syntax--deleted.syntax--punctuation {
      color: @syntax-color-removed;
    }

    &.syntax--only-in {
      // we don't have any methods in diff, so we can safely use this color
      color: @syntax-color-method;
      font-weight: bold;
    }
    &.syntax--header.syntax--git {
      font-weight: bolder;
      background-color: blueviolet;
    }
  }
}