:root {
  --footer-bg: #1a202c; /* 深灰色背景 */
  --footer-text: #a0aec0; /* 浅灰色文本 */
  --footer-heading: #e2e8f0; /* 亮灰色标题 */
  --footer-link-hover: #4fd1c5; /* 链接悬停颜色 - 青色 */
  --footer-divider: #4a5568; /* 分隔线颜色 */
}

.footer {
  background-color: var(--footer-bg);
  color: var(--footer-text);
  padding: 60px 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

.footer .container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 40px; /* 增加间隙 */
  margin-bottom: 40px;
}

.footer-brand,
.footer-section {
  flex: 1;
  min-width: 220px; /* 保证在小屏幕上不会过窄 */
}

.footer-brand h3 {
  color: var(--footer-heading);
  font-size: 24px;
  margin-bottom: 15px;
}

.footer-brand p {
  font-size: 14px;
  line-height: 1.6;
}

.footer-section h3 {
  color: var(--footer-heading);
  font-size: 18px;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 10px;
}

.footer-section h3::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 30px;
  height: 2px;
  background-color: var(--footer-link-hover);
}

.footer-section ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-section ul li {
  margin-bottom: 12px;
}

.footer-section ul li a {
  color: var(--footer-text);
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer-section ul li a:hover {
  color: var(--footer-link-hover);
}

.footer-section ul li i {
  margin-right: 10px;
  color: var(--footer-link-hover);
}

.footer-bottom {
  border-top: 1px solid var(--footer-divider);
  padding-top: 20px;
  text-align: center;
  font-size: 14px;
}