/* 全局重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Microsoft Yahei", Inter, sans-serif;
}

/* 页面基础样式 */
body {
  color: #333;
  background-color: #f8f9fa;
  font-size: 14px;
  line-height: 1.6;
}

a {
  text-decoration: none;
  color: #007bff;
  transition: color 0.3s;
}

a:hover {
  color: #0056b3;
  text-decoration: none;
}

/* 公共头部样式 */
.header {
  background-color: #fff;
  border-bottom: 1px solid #e9ecef;
  padding: 15px 0;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 20px;
  font-weight: 700;
  color: #007bff;
}

.nav-list {
  display: flex;
  list-style: none;
  gap: 30px;
}

.nav-list li a {
  color: #333;
  font-weight: 500;
}

.nav-list li a.active,
.nav-list li a:hover {
  color: #007bff;
}

/* 公共尾部样式 */
.footer {
  background-color: #343a40;
  color: #fff;
  padding: 40px 0 20px;
  margin-top: 50px;
}

.footer .container {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
  margin-bottom: 30px;
}

.footer-col h3 {
  font-size: 16px;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 10px;
}

.footer-col h3::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 40px;
  height: 2px;
  background-color: #007bff;
}

.footer-col ul {
  list-style: none;
}

.footer-col ul li {
  margin-bottom: 10px;
}

.footer-col ul li a {
  color: #ccc;
  transition: color 0.3s;
}

.footer-col ul li a:hover {
  color: #007bff;
}

.copyright {
  text-align: center;
  padding-top: 20px;
  border-top: 1px solid #444;
  color: #ccc;
  font-size: 12px;
}

/* 响应式适配 */
@media (max-width: 768px) {
  .header .container {
    flex-direction: column;
    gap: 15px;
  }

  .nav-list {
    gap: 15px;
  }

  .footer .container {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 576px) {
  .footer .container {
    grid-template-columns: 1fr;
  }
}