Wordpress enqueue styles with child styles (takes into account Bootstrap in this case load bootstrap and then override)

functions_enqueue_child_theme.php

<?php

// Basically we need to make sure we load ALL our stylesheets for our child theme AFTER bootstrap
//   that way we can override bootstrap without using crappy !important overrides, etc.

// This sample uses the transportex theme but just replace that for your own theme.

function my_theme_enqueue_styles() {

  $parent_style = 'transportex-style'; // This is 'twentyfifteen-style' for the Twenty Fifteen theme.
	$theme_colors_style = 'transportex_color';

    // enqueue the parent theme with a dependancy of bootstrap in this case as it overriding stuff!
	wp_enqueue_style( $parent_style, 
		get_template_directory_uri() . '/style.css',
		array( 'bootstrap' )
		);
    
	
	// enqueue child theme style making sure that it comes after bootstrap.
	wp_enqueue_style( 'child-style',
        get_stylesheet_directory_uri() . '/style.css',
        array( $parent_style, 'bootstrap' ),
        wp_get_theme()->get('Version')
    );
	
	// these are just for a particular theme - overriding the colours - get the parent colours then override them.
	wp_enqueue_style($theme_colors_style, get_template_directory_uri() . '/css/colors/default.css');
	wp_enqueue_style( 'child_colors',
        get_stylesheet_directory_uri() . '/default.css',
        array( $parent_style ),
        wp_get_theme()->get('Version')
    );

}
add_action( 'wp_enqueue_scripts', 'my_theme_enqueue_styles' );
?>