(function() {

    var html = document.documentElement;

    var toggle = document.getElementById('theme-toggle');

    var stored = localStorage.getItem('theme');

    if (stored) {

        html.setAttribute('data-theme', stored);

    }

    function updateIcon() {

        if (toggle) {

            toggle.textContent = html.getAttribute('data-theme') === 'dark' ? '\u263D' : '\u2600\uFE0F';

        }

    }

    updateIcon();

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        toggle.addEventListener('click', function() {

            var next = html.getAttribute('data-theme') === 'dark' ? 'light' : 'dark';

            html.setAttribute('data-theme', next);

            localStorage.setItem('theme', next);

            updateIcon();

        });

    }

    // Hamburger menu

    var hamburger = document.getElementById('hamburger');

    var navLinks = document.getElementById('nav-links');

    if (hamburger && navLinks) {

        hamburger.addEventListener('click', function() {

            hamburger.classList.toggle('active');

            navLinks.classList.toggle('open');

        });

        // Close mobile menu when clicking a link

        navLinks.querySelectorAll('a').forEach(function(link) {

            link.addEventListener('click', function() {

                hamburger.classList.remove('active');

                navLinks.classList.remove('open');

            });

        });

    }

    // Dropdown toggles (for mobile tap support)

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            e.preventDefault();

            e.stopPropagation();

            var dropdown = btn.closest('.nav-dropdown');

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                if (other !== dropdown) other.classList.remove('open');

            });

            dropdown.classList.toggle('open');

        });

    });

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            document.querySelectorAll('.nav-dropdown.open').forEach(function(d) {

                d.classList.remove('open');

            });

        }

    });

    // TOC generator for posts with toc: true

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        var headings = document.querySelectorAll('.post-content h1, .post-content h2, .post-content h3');

        if (headings.length > 0) {

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                var level = parseInt(h.tagName.charAt(1));

                if (level < minLevel) minLevel = level;

            });

            var ul = document.createElement('ul');

            headings.forEach(function(h) {

                var level = parseInt(h.tagName.charAt(1));

                var li = document.createElement('li');

                // Indent relative to the highest heading level found

                li.className = 'toc-level-' + (level - minLevel);

                var a = document.createElement('a');

                a.href = '#' + h.id;

                a.textContent = h.textContent;

                li.appendChild(a);

                ul.appendChild(li);

            });

            toc.appendChild(ul);

        }

    }

})();