enhance highlight feature

[Lruihao]

为了更好的适配主题的 dark/light 样式设计，以下必要设置请保持和主题文档一致，尤其是 markup.highlight.noClasses=false

[markup.highlight]
    codeFences = true
    lineNos = true
    lineNumbersInTable = true
    noClasses = false
    # ...

markup.highlight.noClasses=false，意味着 markup.highlight.style 参数失效，若想自定义 hightlight style 可替换掉 _variables.scss 中的相关颜色变量值

[Lruihao]

• https://gohugo.io/content-management/syntax-highlighting
• https://gohugo.io/functions/highlight/
• Unwanted space added to first line of code dillonzq/LoveIt#158
• https://xyproto.github.io/splash/docs/longer/all.html
• https://github.com/alecthomas/chroma/tree/master/styles

可参考 Chroma Style hugo gen chromastyles --style=monokai > monokai.scss

[Lruihao]

Chroma 的样式种类实在太少了，能够配套 dark/light 模式的则是少之又少，有兴趣的可参考 highlightjs 或 prismjs 配色方案

尽可能支持更多编程语言的高亮，例如 diff 等常用的

- theme = "LoveIt"
+ theme = "FixIt"
! enhancements and fixes

---

FixIt 0.2.13 将整合 GitHub 及 Github Dark Dimmed 两种高亮风格

• https://highlightjs.org/static/demo/styles/github.css
• https://highlightjs.org/static/demo/styles/github-dark-dimmed.css

[Lruihao]

已处理完