/* ======= 导航栏样式（桌面 + 移动）======= */

.main-navbar {
  background-color: #fff;
  border-bottom: 1px solid #eee;
  padding: 10px 30px;
}

.navbar-container {
  display: flex;
  justify-content: space-between; /* LOGO 靠左，菜单靠右 */
  align-items: center;
  width: 100%;
}

.site-title {
  font-family: "Helvetica Neue", sans-serif;
  font-size: 1.6rem;
  font-weight: bold;
  text-transform: uppercase;
  color: #222;
}

.nav-menu {
  list-style: none;
  display: flex;
  gap: 30px;
  margin: 0;
  padding: 0;
}

.nav-menu li {
  position: relative;
}

.nav-menu a {
  text-decoration: none;
  color: #333;
  font-weight: 500;
  padding: 6px 8px;
  border-bottom: 2px solid transparent;
  transition: all 0.3s ease;
}

.nav-menu a:hover {
  color: #0077cc;
  border-bottom: 2px solid #0077cc;
}

/* ========= 下拉菜单 ========= */
.dropdown-menu {
  display: none;
  list-style: none;
  position: absolute;
  background: white;
  top: 100%;
  left: 0;
  min-width: 160px;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
  z-index: 1000;
  padding: 10px 0;
}

.dropdown:hover .dropdown-menu {
  display: block;
}

.dropdown-menu a {
  display: block;
  padding: 10px 20px;
  color: #333;
}

.dropdown-menu a:hover {
  background-color: #f0f0f0;
}

/* 导航菜单下拉样式优化 */
nav ul li ul li a {
  font-weight: 100;         /* 细字体（可选值：100、200、300） */
  letter-spacing: 0.5px;    /* 字母间距（越小越紧凑） */
  line-height: 0.8;         /* 行高控制垂直间距 */
  font-size: 12px;          /* 字体大小也可以略调小一点 */
}

/* ========= 移动端菜单 ========= */
@media (max-width: 768px) {
  .navbar-container {
    flex-direction: column;
    align-items: flex-start;
  }

  .nav-menu {
    flex-direction: column;
    gap: 10px;
    width: 100%;
    padding-top: 10px;
    display: none; /* 默认隐藏，点击汉堡菜单再显示 */
  }

  .nav-menu.open {
    display: flex; /* 点击后显示 */
    flex-direction: column;
  }
}

.hamburger {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
}

@media (max-width: 768px) {
  .hamburger {
    display: block;
    margin-left: auto;
  }
}