/* ========== Layout：Header / Footer / Container ========== */

/* ===== Header 吸顶 ===== */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: var(--z-header);
  transition: background var(--t-med) ease-out, box-shadow var(--t-med) ease-out, backdrop-filter var(--t-med);
}
.site-header.is-scrolled {
  background: rgba(14,14,16,0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 1px 0 rgba(255,255,255,0.08);
}
/* 顶部小条 */
.top-bar {
  background: var(--c-ink); color: #a8a5a0; font-size: 12px; border-bottom: 1px solid rgba(255,255,255,0.06);
}
.top-bar .container { display: flex; align-items: center; justify-content: space-between; height: 36px; }
.top-bar .top-info span { margin-right: var(--s-4); }
.top-bar a:hover { color: var(--c-brass); }

/* 主导航 */
.nav-bar { transition: height var(--t-med) ease-out; height: 76px; }
.site-header.is-scrolled .nav-bar { height: 64px; }
.nav-bar .container { display: flex; align-items: center; justify-content: space-between; height: 100%; gap: var(--s-5); }

/* Logo */
.logo { display: flex; flex-direction: column; line-height: 1.1; flex-shrink: 0; }
.logo .logo-cn { font-family: var(--font-serif); font-size: 22px; font-weight: 700; letter-spacing: 0.04em; color: #fff; }
.logo .logo-en { font-family: var(--font-mono); font-size: 10px; letter-spacing: 0.3em; color: var(--c-brass); text-transform: uppercase; }
.site-header:not(.is-scrolled) .nav-bar { background: transparent; }
.site-header:not(.is-scrolled) .nav-bar .logo .logo-cn { color: #fff; }

/* 导航菜单 */
.nav-menu { display: flex; align-items: center; gap: 4px; }
.nav-menu > li > a {
  display: block; padding: 10px 14px; font-size: 15px; color: rgba(255,255,255,0.85);
  position: relative; transition: color var(--t-fast) ease-out;
}
.nav-menu > li > a::after {
  content: ''; position: absolute; left: 14px; right: 14px; bottom: 4px; height: 1px;
  background: var(--c-brass); transform: scaleX(0); transform-origin: left; transition: transform var(--t-fast) ease-out;
}
.nav-menu > li > a:hover, .nav-menu > li.active > a { color: var(--c-brass); }
.nav-menu > li > a:hover::after, .nav-menu > li.active > a::after { transform: scaleX(1); }

/* 右侧操作 */
.nav-actions { display: flex; align-items: center; gap: var(--s-3); flex-shrink: 0; }
.lang-switch { font-family: var(--font-mono); font-size: 12px; color: rgba(255,255,255,0.7); letter-spacing: 0.1em; cursor: pointer; }
.lang-switch:hover { color: var(--c-brass); }

/* 汉堡按钮 */
.hamburger { display: none; flex-direction: column; gap: 5px; padding: 8px; }
.hamburger span { width: 24px; height: 2px; background: #fff; transition: all var(--t-fast) ease-out; }
.hamburger.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.is-open span:nth-child(2) { opacity: 0; }
.hamburger.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* 移动抽屉 */
.mobile-drawer {
  position: fixed; top: 0; right: 0; bottom: 0; width: 80%; max-width: 360px;
  background: var(--c-ink); z-index: var(--z-modal); padding: 80px var(--s-5) var(--s-5);
  transform: translateX(100%); transition: transform var(--t-med) var(--ease-out);
  overflow-y: auto;
}
.mobile-drawer.is-open { transform: none; }
.mobile-drawer .nav-menu { flex-direction: column; align-items: stretch; gap: 0; }
.mobile-drawer .nav-menu > li > a { padding: 16px 0; font-size: 18px; border-bottom: 1px solid rgba(255,255,255,0.08); color: #fff; }
.drawer-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.6); z-index: 999; opacity: 0; visibility: hidden; transition: all var(--t-med); }
.drawer-overlay.is-open { opacity: 1; visibility: visible; }

/* ===== Footer ===== */
.site-footer { background: var(--c-ink); color: #8c8a85; padding-top: var(--s-9); }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: var(--s-7); padding-bottom: var(--s-7); }
.footer-col h4 { color: #fff; font-size: 16px; margin-bottom: var(--s-4); font-family: var(--font-sans); font-weight: 600; letter-spacing: 0.05em; }
.footer-col ul li { margin-bottom: var(--s-2); }
.footer-col ul li a { font-size: 14px; color: #a8a5a0; transition: color var(--t-fast); }
.footer-col ul li a:hover { color: var(--c-brass); }
.footer-brand .logo-cn { font-size: 26px; }
.footer-brand p { font-size: 14px; margin-top: var(--s-3); line-height: 1.8; }
.footer-contact .contact-row { display: flex; align-items: flex-start; gap: 8px; margin-bottom: var(--s-2); font-size: 14px; }
.footer-contact .contact-row svg { flex-shrink: 0; margin-top: 3px; }
.footer-qr { text-align: center; }
.footer-qr .qr-box { width: 120px; height: 120px; margin: 0 auto var(--s-3); background: #fff; padding: 6px; border-radius: 4px; }
.footer-qr .qr-label { font-size: 12px; color: #a8a5a0; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); padding: var(--s-4) 0; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; font-size: 12px; }
.footer-bottom a { color: #6e6b66; }
.footer-bottom a:hover { color: var(--c-brass); }

/* ===== Floating CTA ===== */
.float-cta { position: fixed; right: 20px; bottom: 40px; z-index: var(--z-cta); display: flex; flex-direction: column; gap: 12px; }
.float-btn {
  width: 48px; height: 48px; border-radius: 50%; background: var(--c-ink); color: var(--c-brass);
  display: flex; align-items: center; justify-content: center; box-shadow: var(--shadow-md);
  transition: all var(--t-fast) ease-out; position: relative;
}
.float-btn:hover { background: var(--c-brass); color: #fff; transform: translateY(-2px); }
.float-btn .tooltip {
  position: absolute; right: 60px; top: 50%; transform: translateY(-50%) translateX(8px);
  background: var(--c-ink); color: #fff; padding: 8px 14px; border-radius: 4px; font-size: 13px; white-space: nowrap;
  opacity: 0; visibility: hidden; transition: all var(--t-fast); pointer-events: none;
}
.float-btn:hover .tooltip { opacity: 1; visibility: visible; transform: translateY(-50%) translateX(0); }
.float-btn .tooltip::after { content: ''; position: absolute; right: -6px; top: 50%; transform: translateY(-50%); border: 6px solid transparent; border-left-color: var(--c-ink); }
.float-btn.top { background: var(--c-graphite); }

/* ===== Cookie 条 ===== */
.cookie-bar {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: var(--z-cta); background: var(--c-ink); color: #a8a5a0;
  padding: var(--s-3) var(--s-5); display: flex; align-items: center; justify-content: space-between; gap: var(--s-4);
  transform: translateY(100%); transition: transform var(--t-med); font-size: 13px;
}
.cookie-bar.is-show { transform: none; }
.cookie-bar a { color: var(--c-brass); }

/* ===== 面包屑 ===== */
.breadcrumb { padding: var(--s-5) 0; font-size: 13px; color: var(--c-mist); }
.breadcrumb a { color: var(--c-stone); }
.breadcrumb a:hover { color: var(--c-brass); }
.breadcrumb span { margin: 0 6px; color: var(--c-mist); }

/* 页面顶部留白（吸顶 header） */
.page-offset { padding-top: 112px; }