(function () {
  function initFloatingNav() {
    var toggleInput = document.querySelector('.wc-menu-toggle-input');
    var topbar = document.querySelector('.wc-fixed-topbar');
    var island = document.querySelector('.wc-floating-island');
    var overlay = document.querySelector('.wc-menu-overlay');
    if (!island || island.dataset.wcNavInit) return;
    island.dataset.wcNavInit = '1';

    [toggleInput, topbar, island, overlay].forEach(function (el) {
      if (el && el.parentNode !== document.body) {
        document.body.appendChild(el);
      }
    });

    function luminance(r, g, b) {
      return 0.2126 * r + 0.7152 * g + 0.0722 * b;
    }

    function sampleBackgroundAt(x, y) {
      var stack = document.elementsFromPoint(x, y);
      for (var i = 0; i < stack.length; i++) {
        var el = stack[i];
        if (el === island || island.contains(el)) continue;
        var bg = getComputedStyle(el).backgroundColor;
        var m = bg.match(/rgba?\(([\d]+),\s*([\d]+),\s*([\d]+)(?:,\s*([\d.]+))?\)/);
        if (!m) continue;
        var a = m[4] === undefined ? 1 : parseFloat(m[4]);
        if (a === 0) continue;
        return { r: +m[1], g: +m[2], b: +m[3] };
      }
      var bodyBg = getComputedStyle(document.body).backgroundColor;
      var m2 = bodyBg.match(/rgba?\(([\d]+),\s*([\d]+),\s*([\d]+)/);
      return m2 ? { r: +m2[1], g: +m2[2], b: +m2[3] } : { r: 255, g: 255, b: 255 };
    }

    function updateIslandTheme() {
      var r = island.getBoundingClientRect();
      if (r.width === 0) return;
      var cx = r.left + r.width / 2;
      var cy = r.top + r.height / 2;
      var color = sampleBackgroundAt(cx, cy);
      var lum = luminance(color.r, color.g, color.b);
      island.classList.toggle('wc-island-on-black', lum < 30);
    }

    var ticking = false;
    function onScroll() {
      if (ticking) return;
      ticking = true;
      requestAnimationFrame(function () {
        updateIslandTheme();
        ticking = false;
      });
    }

    window.addEventListener('scroll', onScroll, { passive: true });
    window.addEventListener('resize', onScroll);
    updateIslandTheme();
  }

  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', initFloatingNav);
  } else {
    initFloatingNav();
  }
})();