/* 头部样式 */
.header {
  background: rgba(15, 23, 42, 0.8);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
}

.logo {
  display: flex;
  align-items: center;
}

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

.nav ul {
  display: flex;
  gap: 32px;
  list-style: none;
}

.nav a {
  color: #94a3b8;
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: all 0.3s ease;
  position: relative;
}

.nav a:hover {
  color: #60a5fa;
}

.nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, #60a5fa, #3b82f6);
  transition: width 0.3s ease;
}

.nav a:hover::after {
  width: 100%;
}

.auth-buttons {
  display: flex;
  gap: 12px;
  align-items: center;
}

/* 响应式设计 */
@media (max-width: 768px) {
  .header .container {
    flex-direction: column;
    gap: 12px;
    padding: 12px 15px;
  }
  
  .nav ul {
    gap: 16px;
    flex-wrap: wrap;
    justify-content: center;
  }
  
  .logo img {
    height: 32px;
  }
}