<a href="http://pjdietz.com/wordpress-plugins/custom-css-js/" rel="nofollow ugc">Custom CSS and JS</a> allows you to add stylesheets and JavaScripts to any individual post by adding custom fields. Both CSS and scripts can be either internal or external. Since this is a plugin, the custom CSS and JavaScript are available to any theme used to display the post, as long as the themes call “wp_head”.
<h3>Using the Plugin</h3>
To use the plugin, add any combination of the following custom fields to your post.
custom_css 
Add an external stylesheet by adding a custom field with the name custom_css. The value of the field should be the path to your css file.
cusrom_css_code 
Add an internal stylesheet by adding a custom field with the name custom_css_code. Include your CSS code as the value. (Do not include the style tags.)
custom_js 
Add an external JavaScript by adding a custom field with the name custom_js. The value of the field should be the path to your script.
custom_js_code 
Add an internal JavaScript by adding a custom field with the name custom_js_code. Include your JavaScript code as the value. (Do not include the script tags.)
<h3>Custom Fields Order</h3>
<ol>
<li>The external styles and scripts are included before the internal ones.</li>
<li>If you include multiple entries for a given field, the entries will be included in order.</li>
</ol>
<h3>Okay, but what if I don’t like those tags?</h3>
Just edit custom-css-js.php and change the constants defined near the top of the file.
<h3>Note</h3>
This plugin only works with individual posts and pages. It does not work for list pages (e.g., the index page, search results).

Custom CSS and JS

Custom CSS and JavaScript allows you to add custom internal and external CSS and JavaScripts to individual posts.

dimitris33

This plugin adds suport for the TwentyFifteen theme to the <a href="https://wordpress.org/extend/plugins/styles" rel="ugc">Styles plugin</a>.
About Styles TwentyFifteen
Using this plugin with the Styles plugin you can instantly change the style of the TwentyFifteen theme from the customizer.
Features of the plugin
<ul>
<li>Instant previews</li>
<li>Text size</li>
<li>Google Fonts</li>
<li>Text colors</li>
<li>Border colors</li>
<li>Background colors</li>
<li>Hundreds of options</li>
<li>Consistent interface and names in every theme</li>
<li>Built on WordPress customizer, so Styles grows as WordPress grows</li>
</ul>
Styles and options for all built-in WordPress themes are free. More themes are available at <a href="http://stylesplugin.com" rel="nofollow ugc">StylesPlugin.com</a>.
Free Themes
<ul>
<li>TwentyTen: <a href="http://demo.stylesplugin.com/twentyten" rel="nofollow ugc">Demo</a></li>
<li>TwentyEleven: <a href="http://demo.stylesplugin.com/twentyeleven" rel="nofollow ugc">Demo</a></li>
<li>TwentyTwelve: <a href="http://demo.stylesplugin.com/twentytwelve" rel="nofollow ugc">Demo</a></li>
<li>TwentyThirteen: <a href="http://demo.stylesplugin.com/twentythirteen" rel="nofollow ugc">Demo</a></li>
</ul>
Developer Resources
<ul>
<li><a href="https://github.com/stylesplugin" rel="nofollow ugc">Styles on Github</a></li>
<li><a href="https://github.com/brainstormmedia" rel="nofollow ugc">Brainstorm Media on Github</a></li>
<li>Code Walkthrough: <a href="http://www.youtube.com/playlist?list=PLxj61Fojm1RGevBh10U2qCqjwoH4Awo-P" rel="nofollow ugc">How to add support for your own themes</a></li>
</ul>

Styles: TwentyFifteen

This plugin adds suport for the TwentyFifteen1 theme to the Styles plugin.

Custom CSS and JS vs Styles: TwentyFifteen