let clicked = 0;

function showMenu() {

	const showMenu = document.getElementById('show-menu');
	const menu = document.getElementById('menu');
	
	if(clicked === 0) {
	
		showMenu.className='show-menu clicked';
		
		menu.style.left = 0;
		
		clicked = 1;
		
	}
	
	else {
	
		showMenu.className='show-menu';
		
		menu.style.left = '-250px';
		
		clicked = 0;
		
	}
	
}