.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: #32a2ff;
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  z-index: 1000;
  transition: all 0.3s ease;
}

.header.scrolled {
  background-color: #32a2ff;
  box-shadow: 0 4px 20px rgba(50, 162, 255, 0.3);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  /* 减小头部高度的padding */
  padding: 12px 0;
}

.logo {
  font-size: 28px;
  font-weight: 700;
  color: #ffffff;
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-icon {
  width: 32px;
  height: 32px;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 18px;
  color: #ffffff;
}

.nav {
  display: flex;
  gap: 40px;
  align-items: center;
}

.nav a {
  color: rgba(255, 255, 255, 0.85);
  font-size: 15px;
  font-weight: 500;
  transition: color 0.3s ease;
  position: relative;
}

.nav a:hover,
.nav a.active {
  color: #ffffff;
}

.nav a::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: #ffffff;
  transition: width 0.3s ease;
}

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

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: #ffffff;
  font-size: 24px;
  cursor: pointer;
}

/* 移动端菜单 */
@media (max-width: 768px) {
  .nav {
    position: fixed;
    top: 73px;
    left: 0;
    right: 0;
    background-color: var(--surface);
    flex-direction: column;
    gap: 0;
    padding: 20px;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    border-bottom: 1px solid var(--border);
  }

  .nav.active {
    transform: translateX(0);
  }

  .nav a {
    padding: 15px 0;
    width: 100%;
    border-bottom: 1px solid var(--border);
  }

  .mobile-menu-btn {
    display: block;
  }
}