Hide checkboxes and icons when no CSS in head is loaded

This seems to help in Firefox's reader mode.
Also adjust images to not be huge without CSS.

Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>

layouts/partials/head.html

@@ -30,8 +30,8 @@
     {{ $sidenotes := resources.Get "scss/sidenotes.scss" | resources.ToCSS | resources.Minify }}
     {{ $code := resources.Get "scss/code.scss" | resources.ToCSS | resources.Minify }}
     {{ $icon := resources.Get "img/favicon.png" }}
-    <style>.sidenote-checkbox { display: none; }</style>
-    <style>.feather { width: 1rem; height: 1rem; }</style>
+    <style>.feather { display: inline !important; width: 10px; height: 10px; }</style>
+    <style>img { max-width: 70%; }</style>
     <link rel="stylesheet" href="{{ $style.Permalink }}">
     {{ partial "defercss.html" (dict "url" $sidenotes.Permalink "extra" "") }}
     {{ partial "defercss.html" (dict "url" $code.Permalink "extra" "") }}

layouts/partials/icon.html

@@ -1,4 +1,4 @@
-<svg class="feather">
+<svg class="feather" style="display: none;">
     <use xlink:href="/feather-sprite.svg#{{ . }}"/>
 </svg>
 {{- /* This comment is to remove trailing whitespace */ -}}

layouts/shortcodes/sidenote.html

@@ -1,6 +1,6 @@
 <span class="sidenote">
 <label class="sidenote-label" for="{{- .Get 1 -}}">{{- .Get 2 -}}</label>
-<input class="sidenote-checkbox" type="checkbox" id="{{- .Get 1 -}}"></input>
+<input class="sidenote-checkbox" style="display: none;" type="checkbox" id="{{- .Get 1 -}}"></input>
 {{- if $offset := .Get 3 -}}
 <span class="sidenote-content sidenote-{{- .Get 0 -}}" style="margin-top: {{- $offset -}}rem">
 {{- else -}}