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

:root {
  --color-primary: #1a1a1a;
  --color-secondary: #666;
  --color-accent: #2d4a3d;
  --color-background: #f5f5f5;
  --color-surface: #ffffff;
  --font-heading: "Inter", sans-serif;
  --font-body: "Inter", sans-serif;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 3rem;
  --spacing-xl: 4rem;
  --border-radius: 0.25rem;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-primary);
  background-color: var(--color-background);
  overflow-x: hidden;
}

/* 导航栏 */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  z-index: 1000;
  padding: var(--spacing-sm) 0;
  transition: var(--transition);
}

.navbar-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-logo {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.5rem;
  color: var(--color-primary);
  text-decoration: none;
}

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

.navbar-menu a {
  font-family: var(--font-heading);
  font-weight: 500;
  color: var(--color-secondary);
  text-decoration: none;
  transition: var(--transition);
  position: relative;
}

.navbar-menu a:hover,
.navbar-menu a.active {
  color: var(--color-primary);
}

.navbar-menu a::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width 0.3s ease;
}

.navbar-menu a:hover::after,
.navbar-menu a.active::after {
  width: 100%;
}

/* 主容器 */
.main-container {
  margin-top: 80px;
  min-height: calc(100vh - 80px);
}

/* 页脚 */
.footer {
  text-align: center;
  padding: var(--spacing-md) 0;
  color: var(--color-secondary);
  font-size: 0.9rem;
}

/* 按钮样式 */
.btn {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-primary);
  color: var(--color-surface);
  text-decoration: none;
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: var(--transition);
  font-family: var(--font-heading);
  font-weight: 500;
}

.btn:hover {
  background: var(--color-accent);
  transform: translateY(-2px);
}

.btn-secondary {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
}

.btn-secondary:hover {
  background: var(--color-primary);
  color: var(--color-surface);
}

/* 图片悬停效果 */
.image-hover {
  overflow: hidden;
  cursor: pointer;
}

.image-hover img {
  transition: transform 0.5s ease, filter 0.5s ease;
}

.image-hover:hover img {
  transform: scale(1.05);
  filter: brightness(0.9);
}

/* 模态框 */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.9);
  z-index: 2000;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.modal.active {
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 1;
}

.modal-content {
  max-width: 90%;
  max-height: 90%;
  position: relative;
}

.modal-close {
  position: absolute;
  top: -40px;
  right: 0;
  color: white;
  font-size: 2rem;
  cursor: pointer;
  transition: var(--transition);
}

.modal-close:hover {
  transform: scale(1.1);
}

/* 加载动画 */
.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2px solid rgba(0, 0, 0, 0.1);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* 淡入动画 */
.fade-in {
  animation: fadeIn 0.5s ease forwards;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* 响应式设计 */
@media (max-width: 768px) {
  .navbar-container {
    padding: 0 var(--spacing-sm);
  }
  
  .navbar-menu {
    gap: var(--spacing-md);
  }
  
  .navbar-menu a {
    font-size: 0.9rem;
  }
  
  .navbar-logo {
    font-size: 1.25rem;
  }
  
  .main-container {
    margin-top: 70px;
  }
  
  .modal-content {
    max-width: 95%;
  }
}

@media (max-width: 480px) {
  .navbar-container {
    flex-direction: column;
    gap: var(--spacing-sm);
  }
  
  .navbar-menu {
    gap: var(--spacing-sm);
  }
  
  .main-container {
    margin-top: 100px;
  }
  
  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }
  h3 { font-size: 1.25rem; }
}

/* 滚动条样式 */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-background);
}

::-webkit-scrollbar-thumb {
  background: var(--color-secondary);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-primary);
}