vesica on "Activating child theme results in 500 Internal Server Error"

Hi, I've have custom css modifying the Twenty Fourteen theme on http://www.kimnovakartist.com since we first built it early last year. I've had it contained in the Jetpack Edit css module to preserve it through updates. This weekend we needed to add a function to functions.php to exclude all but one category from the Home page, so I thought I might as well go ahead and make a child theme so that would be preserved through updates as well. Followed the instructions I found in the WP Codex to create style.css and functions.php. Created a directory in Themes for it and uploaded the text files. Activated the child theme, and site immediately went downdue to a 500 internal server error. Is this because I still had the Edit css module of Jetpack activated, or is it for some other reason?
Here's my functions.php:

(<?php)

add_action( 'wp_enqueue_scripts', 'theme_enqueue_styles' );
function theme_enqueue_styles() {
    wp_enqueue_style( 'parent-style', get_template_directory_uri() . '/style.css' );

}

function theme_enqueue_styles() {

    $parent_style = 'parent-style';

    wp_enqueue_style( $parent_style, get_template_directory_uri() . '/style.css' );
    wp_enqueue_style( 'child-style',
        get_stylesheet_directory_uri() . '/style.css',
        array( $parent_style )
    );
}
add_action( 'wp_enqueue_scripts', 'theme_enqueue_styles' );

//Exclude categories from Home.
function exclude_category_home( $query ) {
if ( $query->is_home ) {
$query->set( 'cat', '-1, -234' );
}
return $query;
}

add_filter( 'pre_get_posts', 'exclude_category_home' );

Custom css is a long file, but here's the header:

/*
 Theme Name:   Twenty Fourteen Child
 Theme URI:    http://www.kimnovakartist.com/twentyfourteen-child/
 Description:  Twenty Fourteen Child Theme, developed for www.kimnovakartist.com
 Author:       Hannah West Design
 Author URI:   http://www.hannahwestdesign.com
 Template:     twentyfourteen
 Version:      1.0.0
 License:      GNU General Public License v2 or later
 License URI:  http://www.gnu.org/licenses/gpl-2.0.html
 Tags:         dark, one-column, left-sidebar, responsive-layout
 Text Domain:  twentyfourteen-child
*/

Not sure if I have included everything needed for someone to lend a hand, so let me know if there's anything else you need. Naturally I have switched back to the Twenty Fourteen theme for now. Thanks!