If site wide banner is toggled on, nudge fixed header down

woocommerce_sitewidebanner

  // WOOCOMMERCE – IF SITE WIDE BANNER IS ACTIVE
  // DROP MAIN NAV DOWN
  if ( jQuery('.woocommerce-store-notice').css('display') == "block") {
    $('header.navigation').addClass('drop-low');
  }
  // IF SITE WIDE BANNER IS DISMISSED
  // BRING MAIN NAVIGATION BACK TO TOP
  $('.woocommerce-store-notice__dismiss-link').on('click', function(){
    $('header.navigation.drop-low').removeClass('drop-low');
  })