/* ============================================
   页脚样式 - 深色矩阵
   ============================================ */

footer {
  background: radial-gradient(circle at 15% 30%, rgba(220, 38, 38, 0.08), transparent 30%), var(--color-surface);
  color: #fff;
  padding: 72px 0 40px;
  border-top: 1px solid var(--color-border);
  margin-top: 48px;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

@media (min-width: 992px) { .footer-container { padding: 0 32px; } }

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 28px;
  padding-bottom: 32px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-section h3 {
  margin-bottom: 14px;
  font-size: 18px;
  letter-spacing: 0.2px;
}

.footer-section ul { list-style: none; padding: 0; }
.footer-section li { margin-bottom: 10px; }

.footer-section a {
  color: rgba(255,255,255,0.72);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-section a:hover { color: var(--color-gold); }

.footer-company {
  display: grid;
  gap: 10px;
  color: var(--color-text-weak);
  line-height: 1.6;
}

.footer-company-name {
  font-size: 20px;
  font-weight: 800;
  color: #fff;
}

.footer-company-desc { color: var(--color-muted); font-size: 14px; }

.social-links {
  display: flex;
  gap: 12px;
  margin-top: 4px;
}

.social-links a {
  width: 38px;
  height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: rgba(255,255,255,0.06);
  color: #fff;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.social-links a:hover { background: var(--color-primary); transform: translateY(-2px); }

.footer-contact-item {
  display: grid;
  grid-template-columns: 70px 1fr;
  gap: 8px;
  color: var(--color-muted);
  font-size: 14px;
}

.footer-contact-item strong { color: #fff; font-weight: 700; }

.footer-bottom {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 26px;
  color: var(--color-muted);
  font-size: 14px;
  align-items: center;
  text-align: center;
}

@media (min-width: 768px) {
  .footer-bottom { flex-direction: row; justify-content: space-between; }
}

.footer-bottom-links {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-bottom-links a {
  color: var(--color-text-weak);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-bottom-links a:hover { color: var(--color-gold); }

.copyright { color: rgba(255,255,255,0.5); }

.back-to-top {
  position: fixed;
  right: 22px;
  bottom: 28px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: 1px solid rgba(255,255,255,0.15);
  background: linear-gradient(135deg, rgba(220,38,38,0.9), rgba(169,21,21,0.9));
  color: #fff;
  font-size: 18px;
  display: none;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-soft);
  cursor: pointer;
  transition: all var(--transition-fast);
  z-index: 1100;
}

.back-to-top.show { display: flex; }
.back-to-top:hover { transform: translateY(-3px); box-shadow: var(--shadow-strong); }