(function () {

    /*=====================================
    Sticky
    ======================================= */
    window.onscroll = function () {
        var header_navbar = document.querySelector(".navbar-area");
        var sticky = header_navbar.offsetTop;

        if (window.pageYOffset > sticky) {
            header_navbar.classList.add("sticky");
        } else {
            header_navbar.classList.remove("sticky");
        }



        // show or hide the back-top-top button
        var backToTo = document.querySelector(".scroll-top");
        if (document.body.scrollTop > 50 || document.documentElement.scrollTop > 50) {
            backToTo.style.display = "flex";
        } else {
            backToTo.style.display = "none";
        }
    };

    // section menu active（仅处理页内锚点）
	function onScroll(event) {
		var sections = document.querySelectorAll('.page-scroll');
		var scrollPos = window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop;

		for (var i = 0; i < sections.length; i++) {
			var currLink = sections[i];
			var val = currLink.getAttribute('href');
			if (!val || val.charAt(0) !== '#') {
				continue;
			}
			var refElement = document.querySelector(val);
			if (!refElement) {
				continue;
			}
			var scrollTopMinus = scrollPos + 73;
			if (refElement.offsetTop <= scrollTopMinus && (refElement.offsetTop + refElement.offsetHeight > scrollTopMinus)) {
				sections.forEach(function (link) { link.classList.remove('active'); });
				currLink.classList.add('active');
			} else {
				currLink.classList.remove('active');
			}
		}
	};

    window.document.addEventListener('scroll', onScroll);
    
    // 仅页内锚点（#xxx）平滑滚动；/news、/ 等路由链接正常跳转
    var pageLink = document.querySelectorAll('.page-scroll');

    pageLink.forEach(elem => {
        elem.addEventListener('click', e => {
            var href = elem.getAttribute('href');
            if (!href || href.charAt(0) !== '#') {
                return;
            }
            var target = document.querySelector(href);
            if (!target) {
                return;
            }
            e.preventDefault();
            target.scrollIntoView({
                behavior: 'smooth',
                block: 'start',
            });
        });
    });

    "use strict";

}) ();