Refactor KaTeX shortcode, remove whitespaces and fix font size

layouts/shortcodes/katex.html

@@ -1,13 +1,13 @@
-{{ if not (.Page.Scratch.Get "katex") }}
+{{- if not (.Page.Scratch.Get "katex") -}}
 <!-- Include katext only first time -->
-<link rel="stylesheet" href="{{ "katex/katex.min.css" | relURL }}">
+<link rel="stylesheet" href="{{ "katex/katex.min.css" | relURL }}" />
 <script defer src="{{ "katex/katex.min.js" | relURL }}"></script>
 <script defer src="{{ "katex/auto-render.min.js" | relURL }}" onload="renderMathInElement(document.body);"></script>
-{{ .Page.Scratch.Set "katex" true }}
-{{ end }}
+{{- .Page.Scratch.Set "katex" true -}}
+{{- end -}}
 
-<span class="katex{{ with .Get "class" }} {{ . }}{{ end }}">
-  {{ if in .Params "display" }}\[{{ else }}\({{ end -}}
-  {{ $.Inner }}
-  {{- if in .Params "display" }}\]{{ else }}\){{ end }}
+<span {{- with .Get "class" }} class="{{ . }}"{{ end }}>
+  {{- cond (in .Params "display") "\\[" "\\(" -}}
+  {{- trim .Inner "\n" -}}
+  {{- cond (in .Params "display") "\\]" "\\)" -}}
 </span>