delwinv

A very tiny plugin that adds the ACF field key, field name, Flexible Content field name and Flexible Content layout name to the WYSIWYG 
editor body tag, allowing you to target these classes, along with the existing post-type-* classes added by default by WordPress, in 
your editor-style.css for a better admin/editor experience.
This works for both ACF and ACF Pro, version 5.
<h3>Usage</h3>
<ol>
<li>Install the plugin through the Install Plugins interface or by uploading the <code>acf-plugin-wysiwyg-styling</code> folder to your <code>/wp-content/plugins/</code> directory.</li>
<li>Activate the ACF WYSIWYG Styling plugin from the Admin > Plugins menu.</li>
<li>Create or edit your editor-style.css in your theme directory and use the newly added classes to style your WYSIWYG editors.</li>
</ol>
For example:
<ul>
<li>
The ACF WYSIWYG field with key field_9999ffff11112222 can be targeted with the following CSS:
body.acf-field-key-field_9999ffff11112222 { 
 background-color: red; 
}
</li>
<li>
The ACF WYSIWYG field with key field_9999ffff11112222 in the “room” post type can be targeted with the following CSS:
body.post-type-room.acf-field-key-field_9999ffff11112222 { 
 background-color: blue; 
}
</li>
<li>
All ACF WYSIWYG fields named “my_wysiwyg” can be targetted with the following CSS:
body.acf-field-name-my_wysiwyg { 
 background-color: yellow; 
}
</li>
<li>
All ACF WYSIWYG fields in the Flexible Content field named “page_content” can be targetted with the following CSS:
body.acf-flex-name-page_content { 
 color: green; 
}
</li>
<li>
All ACF WYSIWYG fields in the Flexible Content layout field named “test_layout” can be targetted with the following CSS:
body.acf-layout-test_layout { 
 font-family: “Computer Modern Serif”; 
}
</li>
<li>
The ACF WYSIWYG field named “my_wysiwyg” in the Flexible Content layout field named “test_layout” can be targetted with the following CSS:
body.acf-layout-test_layout.acf-field-name-my_wysiwyg { 
 border: 4px solid red; 
 height: 100%; 
 margin: 0 auto; 
 max-width: 100px; 
}
</li>
</ul>
N.B. I target using the body tag so that a user cannot accidentally target the admin CSS in their edit of the field (regardless of how unlikely 
that would be).

ACF WYSIWYG Styling

Provides the necessary CSS classes in ACF WYSYWIG editor to allow for complete styling of the admin interface.

sarap422

Category Color Pickerは、WordPressのカテゴリーに色を設定して、フロントエンドの投稿一覧やカテゴリーリンクに自動的に色を反映させるプラグインです。
<h4>主な機能</h4>
<ul>
<li>カテゴリー編集画面にカラーピッカーを追加</li>
<li>設定した色をフロントエンドに自動反映</li>
<li>相対輝度に基づく自動テキスト色調整</li>
<li>カスタマイズ可能なCSSセレクタ</li>
<li>カテゴリー一覧での色表示</li>
</ul>
<h4>対応プラグイン・テーマ</h4>
<ul>
<li>VK All in One Expansion Unit</li>
<li>Content Views</li>
<li>一般的なWordPressテーマ</li>
<li>カスタムセレクタで任意の要素に対応</li>
</ul>
<h4>使い方</h4>
<ol>
<li>プラグインを有効化</li>
<li>「投稿」→「カテゴリー」でカテゴリーを編集</li>
<li>カラーピッカーで色を選択</li>
<li>「設定」→「カテゴリーカラー」でセレクタをカスタマイズ（オプション）</li>
</ol>

Category Color Picker

カテゴリーにカラーピッカーを追加し、投稿一覧などに色を反映させるプラグインです。

ACF WYSIWYG Styling vs Category Color Picker