/* ============================================
   Header - 头部导航
   ============================================ */

header {
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 20px;
  background-color: var(--header-bg);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: background-color 0.3s ease;
}

.header-content {
  max-width: var(--content-max-width);
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo img {
  border-radius: 50%;
}

nav ul {
  display: flex;
  list-style: none;
  gap: 20px;
}

nav a {
  text-decoration: none;
  color: var(--text-color);
  font-weight: 500;
}

nav a:hover {
  color: var(--link-color);
}

/* ============================================
   Hero Section - 主视觉区域
   ============================================ */

.hero-section {
  height: 100vh;
  position: relative;
  z-index: 1;
}

main {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 100%;
  padding: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ============================================
   Footer - 页脚
   ============================================ */

footer {
  background-color: var(--footer-bg, #f0f0f0);
  padding: 20px;
  text-align: center;
  transition: background-color 0.3s ease;
}

[data-theme="dark"] footer {
  --footer-bg: #181825;
}

footer p {
  font-size: 0.875rem;
  opacity: 0.6;
}

/* ============================================
   Responsive Design - 响应式设计
   ============================================ */

/* Mobile (default) */
@media (max-width: 767px) {
  .footer-content {
    flex-direction: column;
    text-align: center;
  }
}