Unable to link CSS file

First you need to register the style and css using wp_register_script() and wp_register_style() functions

 //registering css
 wp_register_style ( 'mysample', plugins_url ( 'css/MapStyle.css', __FILE__ ) );
 wp_register_script ( 'mysample', plugins_url ( 'js/MapStyle.js', __FILE__ ) );

After this you can call the wp_enqueue_style() functions for loading the css in required page

wp_enqueue_style('mysample');
wp_enqueue_script('mysample');

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)