I am creating my own theme WordPress, however the CSS I wrote for the theme design is not being applied at all. It’s saved in style.css and I have applied the following in my functions.php file:

<?php

function letters_files() {
  wp_enqueue_style('style',get_stylesheet_uri(),NULL, microtime() );
  wp_enqueue_style('custom-google-fonts', 'https://fonts.googleapis.com/css?family=Amatic+SC|Comfortaa|Cutive+Mono|Dancing+Script|Open+Sans|Roboto');
}

add_action('wp_enqueue_scrips','letters_files');

function letters_features() {
 add_theme_support('title-tag');
 register_nav_menu('FloatingHeaderMenu', 'Floating Header Menu');
 register_nav_menu('footerLocationOne', 'Footer Nav Menu (Footer Menu 1)');
 register_nav_menu('footerLocationTwo', 'Legal Footer Menu (Footer Menu 2)');
}

add_action('after_setup_theme', 'letters_features');

?>

To make sure that the CSS itself isn’t the problem, I have stripped down style.css to something simple to make it clear whether the CSS is working or not:

/*
  Theme Name: Letter Theme
  Author: me
  Version: 1.0
 */

body{
  background-color: green;
  text-align: center;
  font-family: "Courier", arial;
}

It seems that no matter what I try, WordPress just does not recognise the theme’s CSS. Does anyone know any fixes or can anyone see if I’m doing anything wrong here?