/* ============================================
   菁信官网 - 页头 / 页脚 / 导航
   ============================================ */

/* ---------- 页头 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: all 0.3s var(--ease);
}

.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.96);
  border-bottom-color: var(--c-border);
  box-shadow: var(--shadow-sm);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.site-logo img {
  height: 40px;
  width: auto;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.site-nav a {
  position: relative;
  display: block;
  padding: 8px 18px;
  font-size: var(--fs-md);
  font-weight: 500;
  color: var(--c-text);
  border-radius: 8px;
  transition: color 0.25s;
}

.site-nav a::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 2px;
  width: 0;
  height: 3px;
  border-radius: 2px;
  background: var(--c-primary);
  transform: translateX(-50%);
  transition: width 0.3s var(--ease);
}

.site-nav a:hover,
.site-nav a.is-active {
  color: var(--c-primary);
}

.site-nav a:hover::after,
.site-nav a.is-active::after {
  width: 24px;
}

/* 占位栏目（建设中） */
.site-nav a.is-disabled {
  color: var(--c-text-3);
  cursor: not-allowed;
}

.site-nav a.is-disabled:hover {
  color: var(--c-text-3);
}

.site-nav a.is-disabled::after {
  display: none;
}

.site-header__phone {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: var(--fs-lg);
  font-weight: 700;
  color: var(--c-primary);
  flex-shrink: 0;
}

.site-header__phone svg {
  width: 20px;
  height: 20px;
}

/* 汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  border-radius: 2px;
  background: var(--c-navy);
  transition: all 0.3s var(--ease);
}

.nav-toggle.is-open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.is-open span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.is-open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--c-navy);
  color: rgba(255, 255, 255, 0.75);
  padding: 64px 0 0;
  font-size: var(--fs-sm);
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 48px;
}

.site-footer__brand img {
  height: 40px;
  margin-bottom: 16px;
}

.site-footer__brand p {
  max-width: 360px;
  line-height: 1.9;
}

.site-footer h4 {
  color: var(--c-white);
  font-size: var(--fs-lg);
  font-weight: 600;
  margin-bottom: 20px;
}

.site-footer__list li {
  margin-bottom: 12px;
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.site-footer__list svg {
  width: 16px;
  height: 16px;
  margin-top: 4px;
  flex-shrink: 0;
  opacity: 0.6;
}

.site-footer__list a:hover {
  color: var(--c-white);
}

.site-footer__bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  color: rgba(255, 255, 255, 0.45);
}

.site-footer__bottom a:hover {
  color: var(--c-white);
}

/* ---------- 响应式 ---------- */
@media (max-width: 992px) {
  .site-header__phone span {
    display: none;
  }
}

@media (max-width: 768px) {
  .site-header__inner {
    height: 64px;
  }

  .site-logo img {
    height: 32px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--c-white);
    box-shadow: var(--shadow-md);
    padding: 12px 24px 20px;
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s var(--ease);
  }

  .site-nav.is-open {
    transform: none;
    opacity: 1;
    pointer-events: auto;
  }

  .site-nav a {
    padding: 14px 8px;
    border-bottom: 1px solid var(--c-bg-soft);
  }

  .site-nav a::after {
    display: none;
  }

  .site-footer__grid {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .site-footer__bottom {
    justify-content: center;
    text-align: center;
  }
}