/* 移动端导航栏样式优化 */
.nav-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
}
.menu-icon {
  display: block;
  width: 24px;
  height: 3px;
  background: #333;
  position: relative;
}
.menu-icon::before,
.menu-icon::after {
  content: '';
  display: block;
  width: 24px;
  height: 3px;
  background: #333;
  position: absolute;
  left: 0;
}
.menu-icon::before {
  top: -8px;
}
.menu-icon::after {
  top: 8px;
}
@media (max-width: 768px) {
  .nav-menu-btn {
    display: flex;
  }
  .nav-list {
    display: none !important;
  }
  .mobile-menu {
    display: none;
    position: fixed;
    top: 60px;
    left: 0;
    width: 100vw;
    background: #fff;
    box-shadow: 0 2px 16px rgba(0,0,0,0.10);
    border-radius: 0 0 12px 12px;
    z-index: 999;
    padding: 18px 0 12px 0;
    animation: navDropDown 0.25s cubic-bezier(.4,0,.2,1);
  }
  .mobile-menu.open {
    display: block;
  }
  .mobile-menu a {
    display: block;
    margin: 10px 0;
    font-size: 1.1rem;
    width: 90vw;
    text-align: center;
  }
}
@keyframes navDropDown {
  0% { transform: translateY(-30px); opacity: 0; }
  100% { transform: translateY(0); opacity: 1; }
}