modaal-JS

after window.customElements.define('media-gallery', MediaGallery); add

$(document).on('click','button.modaal-close.modaal-toggle, .modaal-overlay.modaal-toggle', function(){		
          	$('.modaal.is-visible').removeClass('is-visible')		
          })		


after: 
// Re-enable 'Add to Cart' button.		      // Re-enable 'Add to Cart' button.
      this.submitBtn.classList.remove('is-loading');		      this.submitBtn.classList.remove('is-loading');
      this.submitBtn.classList.remove('is-success');		      this.submitBtn.classList.remove('is-success');
      this.submitBtn.removeAttribute('aria-disabled');

add

}		
    }else{		
      // if size option is not selected opening a popup		
      $('.modaal').addClass('is-visible');

leave last two  } 
}
as-is

add to end: 
   // Add item from popup and showing in mini cart		
function addItem(v_id, but){		
  but.innerHTML = '✓ Added';		
  but.disabled =  true;		
  let formData = {		
   'items': [{		
    'id': v_id,		
    'quantity': 1		
    }]		
  };		
  fetch(window.Shopify.routes.root + 'cart/add.js', {		
    method: 'POST',		
    headers: {		
      'Content-Type': 'application/json'		
    },		
    body: JSON.stringify(formData)		
  })		
  .then(response => {		
    return response.json();		
  }).then(data =>{		
    console.log(data);		
      but.innerHTML = 'Add To Cart';		
      but.disabled =  false;		
    let cart_form = document.querySelector('cart-form')		
      cart_form.refresh()		
    $('a.cart-link[href="/cart"]')[0].click()		
    $('.modaal-close')[0].click()		
  })		
  .catch((error) => {		
    console.error('Error:', error);		
  });		
  		
}