*, *::before, *::after {
  box-sizing: border-box;
}

body {
  font-family: system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  margin: 0;
  background: url("https://placehold.co/1920x1080/0f172a/1e293b?text=Abstract+Colors") center/cover no-repeat;
  display: flex;
  justify-content: center;
  padding-top: 100px;
  min-height: 100vh;
}

.nav-system {
  position: relative;
}

.menu-trigger {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.2);
  padding: 12px 24px;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

.menu-trigger:hover {
  background: rgba(255, 255, 255, 0.2);
}

.glass-dropdown {
  position: absolute;
  top: 60px;
  left: 0;
  width: 320px;
  /* Container establishes the window frame */
  background: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 16px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
  overflow: hidden;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease;
}

.glass-dropdown.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.panel-container {
  display: flex;
  width: 200%;
  transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.panel-container.shifted {
  transform: translateX(-50%);
}

.menu-panel {
  width: 50%;
  padding: 24px;
  flex-shrink: 0;
}

.panel-title {
  color: #94a3b8;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin: 0 0 16px 0;
}

.menu-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 12px;
  border-radius: 12px;
  cursor: pointer;
  color: #f8fafc;
  transition: background 0.2s;
  margin-bottom: 8px;
}

.menu-item:hover {
  background: rgba(255, 255, 255, 0.1);
}

.item-icon {
  width: 40px;
  height: 40px;
  background: rgba(59, 130, 246, 0.2);
  color: #3b82f6;
  border-radius: 8px;
  display: flex;
  justify-content: center;
  align-items: center;
  font-weight: 700;
  flex-shrink: 0;
}

.item-text h4 {
  margin: 0 0 4px 0;
  font-size: 1rem;
}

.item-text p {
  margin: 0;
  font-size: 0.85rem;
  color: #94a3b8;
}

.menu-item svg {
  margin-left: auto;
  color: #64748b;
}

.back-action {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #3b82f6;
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  margin-bottom: 24px;
}

const btn = document.getElementById("menu-btn");
const dropdown = document.getElementById("dropdown-menu");
const container = document.getElementById("panel-container");

const forwards = document.querySelectorAll(".nav-forward");
const backBtn = document.getElementById("nav-back");

btn.addEventListener("click", function() {
  dropdown.classList.toggle("show");
  // Reset position when reopening
  if (!dropdown.classList.contains("show")) {
    setTimeout(function() {
      container.classList.remove("shifted");
    }, 300);
  }
});

forwards.forEach(function(item) {
  item.addEventListener("click", function() {
    container.classList.add("shifted");
  });
});

backBtn.addEventListener("click", function() {
  container.classList.remove("shifted");
});