/**
 * 尘渊文化 - 通用组件样式
 * 统一的UI组件和工具类
 * @version 2.0.0
 */

/* ========== CSS变量 ========== */
:root {
  /* 主题色 */
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --primary-light: #818cf8;
  --secondary: #0ea5e9;
  --accent: #8b5cf6;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  
  /* 中性色 */
  --dark: #0f172a;
  --dark-light: #1e293b;
  --gray: #64748b;
  --gray-light: #94a3b8;
  --light: #f8fafc;
  --white: #ffffff;
  
  /* 渐变 */
  --gradient-1: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
  --gradient-2: linear-gradient(135deg, #0ea5e9 0%, #6366f1 100%);
  --gradient-3: linear-gradient(135deg, #8b5cf6 0%, #ec4899 100%);
  
  /* 阴影 */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  
  /* 间距 */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  
  /* 圆角 */
  --radius-sm: 0.375rem;
  --radius: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  
  /* 过渡 */
  --transition-fast: 150ms ease;
  --transition: 300ms ease;
  --transition-slow: 500ms ease;
}

/* ========== 重置和基础 ========== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--dark);
  line-height: 1.6;
  background: var(--light);
}

/* ========== 布局组件 ========== */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem;
}

.section {
  padding: 6rem 0;
}

.section-header {
  text-align: center;
  margin-bottom: 3.5rem;
}

/* ========== 导航组件 ========== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  padding: 1rem 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
  z-index: 1030;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--dark);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.brand-icon {
  width: 40px;
  height: 40px;
  background: var(--gradient-1);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-family: 'Ma Shan Zheng', cursive;
}

.navbar-nav {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}

.navbar-nav a {
  color: var(--dark);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
  position: relative;
}

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

/* ========== 按钮组件 ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-lg);
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
  text-decoration: none;
  font-size: 1rem;
}

.btn-primary {
  background: var(--gradient-1);
  color: white;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 20px rgba(99, 102, 241, 0.4);
}

.btn-secondary {
  background: var(--light);
  color: var(--dark);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--primary);
  color: var(--primary);
}

.btn-outline:hover {
  background: var(--primary);
  color: white;
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

/* ========== 卡片组件 ========== */
.card {
  background: white;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
  transition: all 0.3s ease;
  border: 1px solid rgba(0, 0, 0, 0.04);
  overflow: hidden;
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
}

.card-body {
  padding: 1.5rem;
}

/* ========== 标签组件 ========== */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
  font-size: 0.75rem;
  font-weight: 500;
  border-radius: 9999px;
}

/* ========== 表单组件 ========== */
.form-input {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 2px solid #e2e8f0;
  border-radius: var(--radius-lg);
  font-size: 1rem;
  transition: border-color 0.2s;
}

.form-input:focus {
  outline: none;
  border-color: var(--primary);
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  margin-bottom: 0.5rem;
  color: var(--gray);
}

/* ========== 工具类 ========== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: var(--primary); }
.text-secondary { color: var(--secondary); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger { color: var(--danger); }
.text-gray { color: var(--gray); }

.bg-primary { background: var(--primary); }
.bg-light { background: var(--light); }
.bg-white { background: white; }
.bg-dark { background: var(--dark); }

.mt-1 { margin-top: var(--space-1); }
.mt-2 { margin-top: var(--space-2); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }

.mb-1 { margin-bottom: var(--space-1); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }

.hidden { display: none !important; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ========== 网格系统 ========== */
.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.flex {
  display: flex;
}

.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }

.gap-4 { gap: 1rem; }
.gap-6 { gap: 1.5rem; }
.gap-8 { gap: 2rem; }

/* ========== 响应式工具 ========== */
@media (max-width: 768px) {
  .section {
    padding: 4rem 0;
  }
  
  .navbar-nav {
    display: none;
  }
  
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
  
  .section-title {
    font-size: 2rem;
  }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ========== 动画 ========== */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

.animate-fade-in {
  animation: fadeIn 0.6s ease;
}

.animate-slide-up {
  animation: slideUp 0.6s ease;
}

/* ========== 页脚 ========== */
.footer {
  background: var(--dark);
  color: white;
  padding: 4rem 0 2rem;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 2rem;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: white;
}

/* ========== 可访问性 ========== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* 焦点样式 */
:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

/* 跳过链接 */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--primary);
  color: white;
  padding: 8px 16px;
  text-decoration: none;
  z-index: 10000;
  transition: top 0.3s;
}

.skip-link:focus {
  top: 0;
}