Functions.php in child theme that loads CSS file breaks website

Question

I created a child theme and created a functions.php file in the child theme directory that also has the required style.css file and a seperate custom CSS file that I want to load. This is the code I use:

<? php 

add_action('wp_head', 'add_landing_css');
function add_landing_css() {

wp_enqueue_style('landing_css', get_stylesheet_directory_uri().'/landing.css','screen');
}
?>

When I add this code to functions.php every page on my website is blank. It doesn't load anything. When I delete functions.php file my website works as normal. I use a theme called Modest from elegant themes.

Answer 1

The reason for the syntax error is this typo:

<? php 

It should be

<?php 

Secondly, you should use the wp_enqueue_scripts hook instead of the wp_head hook.

Check out the Codex for more info on the wp_enqueue_scripts hook.