/* ============================================================
   nav.css - 导航组件
   
   用途: Header, 移动端导航, 汉堡菜单, 分类导航
   依赖: core/tokens.css
   ============================================================ */

/* ============================================================
   Header - 页头
   ============================================================ */
.pb-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  transition: all var(--transition-base);
}

/* 滚动时玻璃效果 */
.pb-header.is-scrolled {
  background-color: var(--overlay-white-85);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
  border-bottom-color: var(--border-light-80);
  box-shadow: 0 4px 20px var(--overlay-text-06);
}

.pb-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  max-width: var(--container-2xl);
  height: var(--header-height);
  margin-inline: auto;
  padding-inline: var(--space-4);
}

.pb-header__act {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-shrink: 0;
}

.pb-header__contact {
  display: none;
}

/* 移动端强制隐藏在线客服按钮（避免被 .pb-btn 覆盖） */
.pb-header__act .pb-header__contact {
  display: none;
}

.pb-header__topic {
  display: none;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  transition: all var(--transition-fast);
}

.pb-header__topic:hover {
  color: var(--color-primary);
  border-color: var(--color-primary);
  background-color: var(--color-primary-lighter);
}

.pb-header__topic-text {
  display: none;
}

.pb-header__search {
  color: var(--color-text-secondary);
  transition: color var(--transition-fast);
}

.pb-header__search:hover {
  color: var(--color-primary);
}

.pb-header__menu {
  display: flex;
  color: var(--color-text-secondary);
}

/* 移动端强制隐藏专题中心文字 */
.pb-header__topic-text {
  display: none;
}

/* ============================================================
   Brand - Logo
   ============================================================ */
.pb-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  min-width: 0;
  overflow: hidden;
  text-decoration: none;
  color: inherit;
}

.pb-brand img {
  width: 40px;
  height: 40px;
  object-fit: contain;
}

.pb-brand__meta {
  display: flex;
  flex-direction: column;
}

.pb-brand__t {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  line-height: var(--line-height-tight);
}

.pb-brand__s {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

.pb-brand--compact .pb-brand__t {
  font-size: var(--font-size-md);
}

/* ============================================================
   Burger - 汉堡菜单图标
   ============================================================ */
.pb-burger {
  position: relative;
  display: block;
  width: 20px;
  height: 2px;
  background-color: currentColor;
  border-radius: var(--radius-full);
  transition: background-color var(--duration-200) var(--easing-in-out);
}

.pb-burger::before,
.pb-burger::after {
  content: '';
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: currentColor;
  border-radius: var(--radius-full);
  transition: transform var(--duration-200) var(--easing-in-out);
}

.pb-burger::before { top: -6px; }
.pb-burger::after { bottom: -6px; }

.is-open .pb-burger {
  background-color: transparent;
}

.is-open .pb-burger::before {
  transform: translateY(6px) rotate(45deg);
}

.is-open .pb-burger::after {
  transform: translateY(-6px) rotate(-45deg);
}

/* ============================================================
   Navigation - 移动端抽屉导航
   ============================================================ */
.pb-nav {
  position: fixed;
  top: 0;
  right: 0;
  z-index: var(--z-drawer);
  display: flex;
  flex-direction: column;
  width: 100%;
  max-width: 320px;
  height: 100vh;
  background-color: var(--color-bg);
  box-shadow: var(--shadow-2xl);
  transform: translateX(100%);
  transition: transform var(--duration-300) var(--easing-in-out);
  overflow-y: auto;
}

.pb-nav.is-open {
  transform: translateX(0);
}

.pb-nav__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4);
  border-bottom: var(--space-px) solid var(--color-border);
}

.pb-nav__list {
  display: flex;
  flex-direction: column;
  margin: 0;
  padding: var(--space-4);
  list-style: none;
}

.pb-nav__item {
  border-bottom: var(--space-px) solid var(--color-border-light);
}

.pb-nav__row {
  display: flex;
  align-items: center;
  gap: 0.125rem;
}

.pb-nav__link {
  flex: 1;
  display: flex;
  align-items: center;
  padding: var(--space-3) 0;
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
  text-decoration: none;
  transition: color var(--duration-150) var(--easing-in-out);
}

.pb-nav__link:hover,
.pb-nav__item.is-active > .pb-nav__row > .pb-nav__link {
  color: var(--color-primary);
}

/* 展开箭头按钮样式（从 aoyun.base.css 迁移） */
.pb-nav__toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.5rem;
  height: 1.5rem;
  padding: 0;
  background: transparent;
  border: none;
  cursor: pointer;
  color: inherit;
  opacity: 0.5;
  transition: opacity 0.2s ease, transform 0.2s ease;
  flex-shrink: 0;
}

.pb-nav__toggle:hover {
  opacity: 1;
}

.pb-nav__item.is-expanded .pb-nav__toggle,
.pb-nav__item.is-open .pb-nav__toggle {
  transform: rotate(180deg);
}

.pb-nav__sub {
  display: none;
  flex-direction: column;
  margin: 0;
  padding: 0 0 var(--space-3) var(--space-4);
  list-style: none;
}

.pb-nav__item.is-expanded .pb-nav__sub,
.pb-nav__item.is-open .pb-nav__sub {
  display: flex;
}

.pb-nav__sub a {
  display: block;
  padding: var(--space-2) 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--duration-150) var(--easing-in-out);
}

.pb-nav__sub a:hover {
  color: var(--color-primary);
}

.pb-nav__foot {
  margin-top: auto;
  padding: var(--space-4);
  border-top: var(--space-px) solid var(--color-border);
}

.pb-nav__contact {
  width: 100%;
}

/* ============================================================
   Sort Nav - 分类导航
   ============================================================ */
.pb-sortnav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-2);
  min-height: 56px; /* R14: CLS fix - 防止排序导航高度变化 */
  max-width: var(--container-xl);
  margin-inline: auto;
  padding: var(--space-4);
  background-color: var(--color-bg);
  border-bottom: var(--space-px) solid var(--color-border);
}

.pb-sortnav__link {
  padding: var(--space-2) var(--space-4);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  text-decoration: none;
  background-color: var(--color-bg-tertiary);
  border: var(--space-px) solid var(--color-border);
  border-radius: var(--radius-lg);
  transition: background-color var(--duration-150) var(--easing-in-out),
              border-color var(--duration-150) var(--easing-in-out),
              color var(--duration-150) var(--easing-in-out);
}

.pb-sortnav__link:hover {
  color: var(--color-primary);
  border-color: var(--color-primary);
  background-color: var(--color-primary-lighter);
}

.pb-sortnav__link.is-active,
.pb-sortnav__link[aria-current="page"] {
  color: var(--color-text-inverse);
  background-color: var(--color-primary);
  border-color: var(--color-primary);
}

/* ============================================================
   Mobile Bar - 底部导航栏
   ============================================================ */
.pb-mobile-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: var(--z-fixed);
  display: flex;
  align-items: stretch;
  justify-content: space-around;
  height: 56px;
  padding: 0 env(safe-area-inset-right, 0) env(safe-area-inset-bottom, 0) env(safe-area-inset-left, 0);
  background-color: var(--color-bg);
  border-top: var(--space-px) solid var(--color-border);
  box-shadow: 0 -2px 10px var(--overlay-black-08);
}

.pb-mobile-bar__item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  min-width: 64px;
  max-width: 96px;
  padding: var(--space-2) var(--space-2);
  font-size: 11px;
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--duration-150) var(--easing-in-out),
              background-color var(--duration-150) var(--easing-in-out);
}

.pb-mobile-bar__item .pg-ico,
.pb-mobile-bar__item svg,
.pb-mobile-bar__item img {
  width: 22px;
  height: 22px;
  flex-shrink: 0;
}

.pb-mobile-bar__item:hover,
.pb-mobile-bar__item.is-active {
  color: var(--color-primary);
  background-color: var(--color-primary-lighter);
}

.pb-mobile-bar__item--cta {
  flex: 1.2;
  color: var(--color-text-inverse);
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  margin-top: -4px;
  padding-top: var(--space-3);
}

.pb-mobile-bar__item--cta:hover {
  color: var(--color-text-inverse);
  background: linear-gradient(135deg, var(--color-primary-hover) 0%, var(--color-primary-dark) 100%);
}

/* 导航抽屉打开时隐藏底部固定底栏 */
body.nav-open .pb-mobile-bar {
  display: none;
}

/* ============================================================
   Responsive - 768px+
   ============================================================ */
@media (min-width: 768px) {
  .pb-header__inner {
    height: var(--header-height);
    padding-inline: var(--space-6);
  }

  /* 768px+ 隐藏汉堡按钮，显示桌面导航 */
  /* 768px+ 强制隐藏汉堡按钮（避免被 .pb-btn 覆盖） */
  .pb-header__act .pb-header__menu {
    display: none;
  }

  .pb-header__act .pb-header__contact {
    display: flex;
  }

  .pb-header__topic {
    display: flex;
  }

  .pb-header__topic-text {
    display: inline;
  }

  /* 768px+ 导航改为水平模式 */
  .pb-nav {
    position: static;
    flex-direction: row;
    width: auto;
    max-width: none;
    height: auto;
    background-color: transparent;
    box-shadow: none;
    transform: none;
    overflow: visible;
  }

  .pb-nav__head {
    display: none;
  }

  .pb-nav__list {
    flex-direction: row;
    gap: var(--space-1);
    padding: 0;
  }

  .pb-nav__item {
    position: relative;
    border-bottom: none;
  }

  .pb-nav__link {
    padding: var(--space-2) var(--space-3);
    font-size: var(--font-size-sm);
    border-radius: var(--radius-md);
  }

  .pb-nav__link:hover {
    background-color: var(--color-bg-secondary);
  }

  .pb-nav__toggle {
    display: none;
  }

  .pb-nav__sub {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 200px;
    padding: var(--space-2);
    background-color: var(--color-bg);
    border: var(--space-px) solid var(--color-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px);
    transition: opacity var(--duration-200) var(--easing-in-out),
                visibility var(--duration-200) var(--easing-in-out),
                transform var(--duration-200) var(--easing-in-out);
  }

  .pb-nav__item:hover .pb-nav__sub {
    display: flex;
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .pb-nav__sub a {
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-md);
  }

  .pb-nav__sub a:hover {
    background-color: var(--color-bg-secondary);
  }

  .pb-nav__foot {
    display: none;
  }

  /* 隐藏移动端底栏 */
  .pb-mobile-bar {
    display: none;
  }
}

/* ============================================================
   Responsive - 1024px+ (仅增量调整)
   ============================================================ */
@media (min-width: 1024px) {
  .pb-header__inner {
    padding-inline: var(--space-8);
  }
}

/* ============================================================
   Nav 补充组件（从 aoyun.base.css 迁移）
   ============================================================ */
.pb-nav__close {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-2);
  background: transparent;
  border: none;
  cursor: pointer;
}

.pb-nav__text {
  font-size: var(--font-size-sm);
}