/* 桌面端：坚决隐藏折叠按钮，不占空间 */
.submenu-toggle {
  display: none !important;
}

/* 移动端样式 (Ananke 默认断点通常是 60em / 960px) */
@media screen and (max-width: 60em) {
  /* 1. 强制主菜单项垂直排列，占满宽度 */
  nav ul li {
    display: block !important;
    width: 100%;
    border-bottom: 1px solid rgba(0,0,0,0.05); /* 可选：加个分割线更好看 */
    position: relative;
  }

  /* 2. 链接：给右侧的按钮留出空间，防止误触 */
  nav ul li.has-submenu > a {
    display: block;
    padding-right: 3rem; 
  }

  /* 3. 子菜单样式：默认隐藏，取消绝对定位(关键)，去掉阴影 */
  nav ul li ul {
    display: none !important;
    position: static !important; /* 让子菜单占据文档流空间，而不是悬浮 */
    width: 100% !important;
    box-shadow: none !important;
    padding-left: 2rem; /* 缩进效果 */
    background-color: rgba(0,0,0,0.03); /* 可选：轻微背景色区分 */
  }

  /* 4. 激活状态显示子菜单 */
  nav ul li ul.show-submenu {
    display: block !important;
  }

  /* 显示折叠按钮 */
  .submenu-toggle {
    display: flex !important;
    align-items: center;
    justify-content: center;
    position: absolute;
    right: 0;
    top: 0;
    bottom: 0;
    width: 3rem; /* 易于点击的区域 */
    cursor: pointer;
    font-weight: bold;
    font-size: 1.5rem;
    z-index: 100;
    color: inherit;
  }
}