nickdavis/functions.php

## functions.php
<?php

add_filter( 'language_attributes', 'add_no_js_class_to_html_tag', 10, 2 );
/**
 * Add 'no-js' class to <html> tag in order to work with Modernizr.
 *
 * (Modernizr will change class to 'js' if JavaScript is supported).
 *
 * @since 1.0.0
 *
 * @param string $output A space-separated list of language attributes.
 * @param string $doctype The type of html document (xhtml|html).
 *
 * @return string $output A space-separated list of language attributes.
 */
function add_no_js_class_to_html_tag( $output, $doctype ) {
	if ( 'html' !== $doctype ) {
		return $output;
	}

	$output .= ' class="no-js"';

	return $output;
}
	<?php

	add_filter( 'language_attributes', 'add_no_js_class_to_html_tag', 10, 2 );
	/**
	* Add 'no-js' class to <html> tag in order to work with Modernizr.
	*
	* (Modernizr will change class to 'js' if JavaScript is supported).
	*
	* @since 1.0.0
	*
	* @param string $output A space-separated list of language attributes.
	* @param string $doctype The type of html document (xhtml\|html).
	*
	* @return string $output A space-separated list of language attributes.
	*/
	function add_no_js_class_to_html_tag( $output, $doctype ) {
	if ( 'html' !== $doctype ) {
	return $output;
	}

	$output .= ' class="no-js"';

	return $output;
	}