how to go to a porfolio category from the mega menu ?

Hello,

Use the link href in this format: href="page.html#filter=.pf-graphics" and then you can simply add the following JS Codes at the bottom of the Portfolio Page:
[ch_pre]
jQuery(window).on( 'pluginIsotopeReady', function(){

	let $container = $('.grid-container');

	function getHashFilter() {
		let hash = location.hash;
		// get filter=filterName
		let matches = location.hash.match( /filter=([^&]+)/i );
		let hashFilter = matches && matches[1];
		return hashFilter && decodeURIComponent( hashFilter );
	}

	function onHashchange() {
		let hashFilter = getHashFilter();
		if ( !hashFilter ) {
			return;
		}
		// filter isotope
		$container.isotope({ filter: hashFilter });
		// set selected class on button
		if ( hashFilter ) {
			$('.grid-filter li').removeClass('activeFilter');
			$('.grid-filter li').find('[data-filter="' + hashFilter + '"]').parent('li').addClass('activeFilter');
		}
	}

	$(window).on( 'hashchange', onHashchange );
	// trigger event handler to init Isotope
	onHashchange();

});

[/ch_pre]

This will definitely work fine. Hope this Helps!

Let us know if we can help you with anything else or if you find any further issues.

Hello,

1. Yes sure, you can use this JS Code in some other JS File.

2. You can consider adding the updating the JS Codes with the following:
   [ch_pre]
   jQuery(window).on( 'pluginIsotopeReady', function(){

    let $container = $('.grid-container');
   
    function getHashFilter() {
        let hash = location.hash;
        // get filter=filterName
        let matches = location.hash.match( /filter=([^&]+)/i );
        let hashFilter = matches && matches[1];
        return hashFilter && decodeURIComponent( hashFilter );
    }
   
    function onHashchange() {
        let hashFilter = getHashFilter();
        if ( !hashFilter ) {
            return;
        }
        console.log( hashFilter );
        // filter isotope
        $container.isotope({ filter: hashFilter });
        // set selected class on button
        if ( hashFilter ) {
            $('.grid-filter li').removeClass('activeFilter');
            $('.grid-filter li').find('[data-filter="' + hashFilter + '"]').parent('li').addClass('activeFilter');
   
            let filterElOff    = $('[data-filter="' + hashFilter + '"]').offset().top;
            $('html,body').stop(true, true).animate({
                'scrollTop': filterElOff - 100
            }, 1250, 'easeInOutQuad');
        }
    }
   
    $(window).on( 'hashchange', onHashchange );
    // trigger event handler to init Isotope
    onHashchange();

   });
   [/ch_pre]

This will definitely work fine. Hope this Helps!

Let us know if we can help you with anything else or if you find any further issues.