/* =========================================================
   信联天地 · Header / Footer / 导航
   ========================================================= */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 14px 0;
  background: rgba(255, 255, 255, .86);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: all .3s var(--ease);
}
.site-header.is-scrolled {
  background: rgba(255, 255, 255, .95);
  border-bottom-color: var(--c-gray-200);
  box-shadow: var(--sh-sm);
}
.site-header__wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 18px;
  letter-spacing: -.01em;
  color: var(--t-primary);
}
.brand__mark {
  width: 32px; height: 32px;
  border-radius: 6px;
  background: var(--c-navy);
  color: var(--c-gold);
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 16px;
}
.nav {
  display: flex;
  align-items: center;
  gap: 6px;
}
.nav a {
  padding: 8px 14px;
  font-size: 14px;
  color: var(--t-secondary);
  border-radius: 6px;
  transition: color .2s;
}
.nav a:hover, .nav a.is-active { color: var(--c-navy); }
.nav a.is-active { font-weight: 500; }

.header-cta {
  display: flex;
  align-items: center;
  gap: 12px;
}
.header-cta .btn { padding: 10px 18px; font-size: 14px; }

.menu-toggle {
  display: none;
  width: 40px; height: 40px;
  border: 1px solid var(--c-gray-200);
  border-radius: 8px;
  background: transparent;
  position: relative;
}
.menu-toggle span {
  position: absolute; left: 10px; right: 10px; height: 2px; background: var(--t-primary);
  transition: all .25s var(--ease);
}
.menu-toggle span:nth-child(1) { top: 14px; }
.menu-toggle span:nth-child(2) { top: 19px; }
.menu-toggle span:nth-child(3) { top: 24px; }
.menu-toggle.is-open span:nth-child(1) { top: 19px; transform: rotate(45deg); }
.menu-toggle.is-open span:nth-child(2) { opacity: 0; }
.menu-toggle.is-open span:nth-child(3) { top: 19px; transform: rotate(-45deg); }

/* 移动端菜单 */
.mobile-menu {
  display: none;
  position: fixed;
  inset: 64px 0 0 0;
  background: #fff;
  padding: 24px;
  z-index: 99;
  overflow-y: auto;
}
.mobile-menu.is-open { display: block; }
.mobile-menu a {
  display: block;
  padding: 16px 4px;
  border-bottom: 1px solid var(--c-gray-100);
  font-size: 17px;
  font-weight: 500;
}
.mobile-menu__cta { margin-top: 24px; display: flex; flex-direction: column; gap: 12px; }

/* Footer */
.site-footer {
  background: var(--c-graphite);
  color: rgba(255,255,255,.72);
  padding: 64px 0 32px;
  font-size: 14px;
}
.site-footer__grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}
.site-footer h5 {
  color: #fff;
  font-size: 14px;
  letter-spacing: .04em;
  text-transform: uppercase;
  margin-bottom: 18px;
  font-weight: 500;
}
.site-footer ul li { margin-bottom: 10px; }
.site-footer a:hover { color: var(--c-gold); }
.site-footer__brand { font-size: 18px; color: #fff; font-weight: 600; margin-bottom: 16px; }
.site-footer__desc { color: rgba(255,255,255,.6); line-height: 1.7; margin-bottom: 20px; }
.site-footer__contact { display: flex; flex-direction: column; gap: 8px; color: rgba(255,255,255,.85); }
.site-footer__contact strong { color: #fff; }
.site-footer__bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  color: rgba(255,255,255,.5);
  font-size: 13px;
}

/* 浮动侧栏（PC） */
.floating-cta {
  position: fixed;
  right: 24px;
  bottom: 32px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  z-index: 90;
}
.floating-cta .fab {
  width: 56px; height: 56px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--c-navy);
  color: #fff;
  font-size: 20px;
  border: none;
  cursor: pointer;
  box-shadow: var(--sh-md);
  transition: transform .25s var(--ease);
  position: relative;
}
.floating-cta .fab:hover { transform: translateY(-2px) scale(1.04); }
.floating-cta .fab--wechat { background: #1AAD19; }
.floating-cta .fab__label {
  position: absolute;
  right: 64px;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(20,23,31,.92);
  color: #fff;
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 12px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity .2s;
}
.floating-cta .fab:hover .fab__label { opacity: 1; }

/* 移动端底部固定 CTA */
.mobile-bottom-cta {
  display: none;
  position: fixed;
  left: 0; right: 0; bottom: 0;
  z-index: 95;
  background: #fff;
  border-top: 1px solid var(--c-gray-200);
  padding: 10px 16px calc(10px + env(safe-area-inset-bottom));
  gap: 10px;
}
.mobile-bottom-cta .btn { flex: 1; padding: 12px; font-size: 14px; }

/* 微信弹窗 */
.wechat-modal {
  position: fixed;
  inset: 0;
  background: rgba(20,23,31,.55);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 200;
  padding: 24px;
}
.wechat-modal.is-open { display: flex; }
.wechat-modal__panel {
  background: #fff;
  border-radius: var(--r-lg);
  padding: 32px;
  max-width: 360px;
  width: 100%;
  text-align: center;
  box-shadow: var(--sh-lg);
}
.wechat-modal__panel h4 { font-size: 20px; margin-bottom: 8px; }
.wechat-modal__panel p { color: var(--t-secondary); margin-bottom: 20px; font-size: 14px; }
.wechat-modal__qr {
  width: 220px; height: 220px;
  margin: 0 auto 16px;
  background: var(--c-gray-100);
  border-radius: var(--r-md);
  display: grid;
  place-items: center;
  color: var(--t-muted);
  font-size: 13px;
}
.wechat-modal__id {
  font-family: 'Inter', monospace;
  background: var(--c-gray-100);
  padding: 8px 12px;
  border-radius: 6px;
  display: inline-block;
  margin-bottom: 8px;
  font-size: 14px;
}
.wechat-modal__close {
  margin-top: 12px;
  background: transparent;
  border: 1px solid var(--c-gray-300);
  padding: 10px 24px;
  border-radius: 999px;
}

/* 返回顶部 */
.back-top {
  position: fixed;
  right: 24px;
  bottom: 160px;
  width: 44px; height: 44px;
  border-radius: 50%;
  border: 1px solid var(--c-gray-200);
  background: rgba(255,255,255,.9);
  backdrop-filter: blur(8px);
  display: none;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 80;
  font-size: 18px;
}
.back-top.is-show { display: flex; }