/* —— 默认按钮隐藏（PC端不显示） —— */
.menu-icon {
  display: none;
  width: 30px;
  height: 22px;
  flex-direction: column;
  justify-content: space-between;
  cursor: pointer;
  margin-right: 15px;
  z-index: 10010;
}
.menu-icon span {
  display: block;
  height: 3px;
  width: 100%;
  background: #fff;
  border-radius: 2px;
}

/* —— 手机端显示按钮，隐藏原始导航 —— */
@media (max-width: 991px) {
  .menu-icon {
    display: flex;  /* ✅ 小屏幕才显示按钮 */
    position: fixed; 
    top: 12px;
    left: 12px;
    z-index: 10010;
  }
  header nav {
    display: none;  /* ✅ 小屏幕隐藏导航条，避免挡住按钮 */
  }
}

/* 遮罩层 */
.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  z-index: 10000;
  display: none;
}
.overlay.show { display: block; }

/* 侧边菜单（抽屉式） */
.side-menu {
  position: fixed;
  top: 0; left: 0;
  height: 100vh;
  width: 100vw;
  background: #000;
  z-index: 10005;
  overflow-y: auto;
  transform: translateX(-100%);
  transition: transform .3s ease;
  padding-top: 60px;
}
.side-menu.open { transform: translateX(0); }
.menu-links {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-top: 20px;
}
.menu-links a {
  color: #fff;
  text-decoration: none;
  font-size: 18px;
  padding: 12px 0;
  width: 100%;
  text-align: center;
}
.menu-links a:hover {
  background: #111;
}