Enqueue styles in Plugin

wds_enqueue_styles_in_plugin.php

<?php
function my_plugin_enqueue() {
    $file_path = plugin_dir_path( __FILE__ ) . 'css/styles.css';
    $version = filemtime( $file_path );
    wp_register_style( 
        'my_plugin_main_css', 
        plugins_url( '/css/styles.css', __FILE__ ), 
        array(), 
        $version
    );
    wp_enqueue_style( 'my_plugin_main_css' );
}

add_action( 'wp_enqueue_scripts', 'my_plugin_enqueue' );