/* ===== 导航栏基础样式 ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 75px;
  background-color: var(--color-bg-primary);
  z-index: var(--z-fixed);
  transition: box-shadow var(--transition-normal);
}

.navbar--scrolled {
  box-shadow: var(--shadow-md);
}

.navbar__container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

/* Logo */
.navbar__logo {
  display: flex;
  align-items: center;
}

.navbar__logo img {
  height: 40px;
  width: auto;
}

/* 菜单 */
.navbar__menu {
  display: flex;
  align-items: center;
}

.navbar__list {
  display: flex;
  gap: var(--space-8);
  list-style: none;
  margin: 0;
  padding: 0;
}

.navbar__link {
  font-size: var(--text-base);
  font-weight: var(--font-medium);
  color: var(--color-text-primary);
  padding: var(--space-2) var(--space-3);
  position: relative;
  transition: color var(--transition-fast);
}

.navbar__link:hover,
.navbar__link--active {
  color: var(--color-primary);
}

.navbar__link--active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 3px;
  background-color: var(--color-primary);
}

/* CTA按钮 */
.navbar__cta {
  margin-left: var(--space-6);
}

/* 汉堡按钮 */
.navbar__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 30px;
  height: 30px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
}

.navbar__toggle-bar {
  width: 100%;
  height: 3px;
  background-color: var(--color-text-primary);
  border-radius: 2px;
  transition: all var(--transition-normal);
}

/* 汉堡按钮激活状态 */
.navbar__toggle--active .navbar__toggle-bar:nth-child(1) {
  transform: rotate(45deg) translate(6px, 6px);
}

.navbar__toggle--active .navbar__toggle-bar:nth-child(2) {
  opacity: 0;
}

.navbar__toggle--active .navbar__toggle-bar:nth-child(3) {
  transform: rotate(-45deg) translate(6px, -6px);
}

/* ===== 响应式 ===== */
@media (max-width: 767px) {
  .navbar__toggle {
    display: flex;
  }

  .navbar__menu {
    position: fixed;
    top: 75px;
    left: 0;
    right: 0;
    background-color: var(--color-bg-primary);
    padding: var(--space-6);
    box-shadow: var(--shadow-lg);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
  }

  .navbar__menu--open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .navbar__list {
    flex-direction: column;
    gap: var(--space-4);
  }

  .navbar__link {
    display: block;
    padding: var(--space-3);
  }
}

/* 页面内容偏移（为固定导航栏留空间） */
main {
  padding-top: 75px;
}