modif header in calendar

I want to change the width of the div month-input in the full calendar. This is the php code that the plugin send to the server:

<div class="month input">
		<?php if( empty($args['calendar_month_nav']) ):	?>
			<form action="" method="get">
				<input type="month" class="em-month-picker" value="<?php echo $EM_DateTime->i18n('Y-m') ?>" data-month-value="<?php echo $EM_DateTime->i18n('F Y') ?>">
				<span class="toggle"></span>
			</form>
		<?php else: ?>
			<?php echo esc_html($EM_DateTime->i18n(get_option('dbem_full_calendar_month_format'))); ?>
		<?php endif; ?>
	</div>

and this is the code that i see in my browser

<div class="month input">
					<form action="" method="get">
				<input type="text" class="em-month-picker flatpickr-input select-toggle active" value="2023-09" data-month-value="septiembre 2023" style="width: 224.859px !important;" readonly="readonly">
				<span class="toggle"></span>
			<select style="display:none;visibility:hidden;"><option></option></select></form>
			</div>

I need to change the value of style="width: 224.859px !important;" but i don’t know how. in the php code there isn’t any style label and i’ve tryed with CSS styles but it’s not working.

.em-month-picker { width: auto; }

I’ve also tryed to look for the variable $args['calendar_month_nav'] but i couldn’t find it.

Anybody knows how can i change this value?

Thnks