/* === 设计令牌 === */
:root {
  /* 颜色 */
  --color-primary: #000000;
  --color-secondary: #ffffff;
  --color-accent: #f5f5f5;
  --color-text-muted: #666666;
  
  /* 间距 */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  
  /* 排版 */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-size-base: 1rem;
  --font-size-lg: 1.25rem;
  --font-size-xl: 3rem;
  
  /* 圆角 */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
}

/* === 全局样式 === */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-family);
  color: var(--color-primary);
  background-color: var(--color-secondary);
  line-height: 1.6;
  overflow-x: hidden;
}

/* === 导航栏 === */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  z-index: 1000;
  padding: var(--spacing-sm) 0;
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 var(--spacing-md);
}

.nav-logo {
  font-size: var(--font-size-lg);
  font-weight: 300;
  letter-spacing: 2px;
}

.nav-menu {
  display: flex;
  gap: var(--spacing-lg);
  list-style: none;
}

.nav-link {
  text-decoration: none;
  color: var(--color-primary);
  font-size: var(--font-size-base);
  transition: opacity 0.3s ease;
}

.nav-link:hover {
  opacity: 0.6;
}

/* === 轮播图 === */
.carousel {
  position: relative;
  width: 100%;
  height: 100vh;
  overflow: hidden;
}

.carousel-item {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 1s ease-in-out;
}

.carousel-item.active {
  opacity: 1;
}

.carousel-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.carousel-caption {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  color: var(--color-secondary);
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

.carousel-title {
  font-size: var(--font-size-xl);
  font-weight: 300;
  letter-spacing: 3px;
  margin-bottom: var(--spacing-sm);
}

/* === 内容区域 === */
.content {
  padding: var(--spacing-lg) var(--spacing-md);
  max-width: 1200px;
  margin: 0 auto;
}

.section-title {
  font-size: 2rem;
  font-weight: 300;
  text-align: center;
  margin-bottom: var(--spacing-lg);
  letter-spacing: 1px;
}

/* === 网格布局 === */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.grid-item {
  position: relative;
  overflow: hidden;
  cursor: pointer;
  background-color: var(--color-accent);
}

.grid-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease, filter 0.3s ease;
}

.grid-item:hover .grid-image {
  transform: scale(1.05);
  filter: brightness(1.1);
}

.grid-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(transparent, rgba(0, 0, 0, 0.7));
  color: var(--color-secondary);
  padding: var(--spacing-md);
  transform: translateY(100%);
  transition: transform 0.3s ease;
}

.grid-item:hover .grid-overlay {
  transform: translateY(0);
}

/* === 理念页面 === */
.philosophy-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
  font-size: var(--font-size-lg);
  line-height: 1.8;
  color: var(--color-text-muted);
}

/* === 页脚 === */
.footer {
  text-align: center;
  padding: var(--spacing-md) 0;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  border-top: 1px solid rgba(0, 0, 0, 0.1);
  margin-top: var(--spacing-lg);
}

/* === 响应式设计 === */
@media (max-width: 768px) {
  .nav-menu {
    gap: var(--spacing-md);
  }
  
  .carousel-title {
    font-size: 2rem;
  }
  
  .section-title {
    font-size: 1.5rem;
  }
  
  .philosophy-content {
    font-size: var(--font-size-base);
  }
}

@media (max-width: 480px) {
  .nav-menu {
    flex-direction: column;
    gap: var(--spacing-sm);
  }
  
  .carousel-caption {
    padding: 0 var(--spacing-sm);
  }
  
  .carousel-title {
    font-size: 1.5rem;
  }
  
  .grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-sm);
  }
}