/* WeKnowPortal - 智能知识管理平台样式 */
/* 基于 TDesign 设计系统的现代化设计 */

/* 基础变量 */
:root {
  /* 颜色系统 */
  --primary-color: #0052d9;
  --primary-hover: #0042a7;
  --primary-light: #e0ebff;
  --secondary-color: #ff7d00;
  --success-color: #00a870;
  --warning-color: #ff7d00;
  --error-color: #e34d59;
  --info-color: #0052d9;
  
  /* 中性色 */
  --text-primary: #000000e6;
  --text-secondary: #00000099;
  --text-tertiary: #00000066;
  --text-disabled: #00000040;
  --bg-color: #ffffff;
  --bg-color-page: #f3f5f7;
  --bg-color-container: #ffffff;
  --bg-color-secondary: #f3f5f7;
  --border-color: #e7e7e7;
  --border-level-1: #e7e7e7;
  --border-level-2: #dcdcdc;
  --shadow-1: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-2: 0 4px 16px rgba(0, 0, 0, 0.12);
  --shadow-3: 0 8px 24px rgba(0, 0, 0, 0.16);
  
  /* 间距 */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-xxl: 48px;
  
  /* 字体 */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --font-size-xs: 12px;
  --font-size-sm: 14px;
  --font-size-md: 16px;
  --font-size-lg: 18px;
  --font-size-xl: 20px;
  --font-size-xxl: 24px;
  --font-size-xxxl: 32px;
  
  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;
  
  /* 动画 */
  --transition-fast: 0.2s;
  --transition-normal: 0.3s;
  --transition-slow: 0.4s;
}

/* 重置样式 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-sm);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-color-page);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* 容器 */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

/* 导航栏 */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-level-1);
  z-index: 1000;
  transition: all var(--transition-normal);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  height: 64px;
}

.nav-left {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
}

.nav-logo {
  font-size: var(--font-size-xxl);
  font-weight: 800;
  color: var(--primary-color);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.nav-logo:hover {
  color: var(--primary-hover);
}

.nav-menu {
  display: flex;
  gap: var(--spacing-lg);
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: var(--font-size-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.nav-link:hover {
  color: var(--primary-color);
  background-color: var(--primary-light);
}

.nav-link.active {
  color: var(--primary-color);
  background-color: var(--primary-light);
  font-weight: 500;
}

.nav-right {
  display: flex;
  gap: var(--spacing-sm);
}

.nav-btn {
  padding: var(--spacing-sm) var(--spacing-lg);
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
  font-weight: 500;
}

.nav-btn-secondary {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-level-1);
  text-decoration: none;
}

.nav-btn-secondary:hover {
  background: var(--bg-color-secondary);
  border-color: var(--border-level-2);
  text-decoration: none;
}

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

.nav-btn-primary:hover {
  background: var(--primary-hover);
}

/* 英雄区域 */
.hero {
  position: relative;
  min-height: 80vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: 64px;
}

.hero-background {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: -1;
}

.hero-gradient {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
  opacity: 0.15;
}

.hero-pattern {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 50%, rgba(102, 126, 234, 0.3) 0%, transparent 50%),
    radial-gradient(circle at 80% 50%, rgba(118, 75, 162, 0.3) 0%, transparent 50%),
    radial-gradient(circle at 50% 80%, rgba(240, 147, 251, 0.2) 0%, transparent 40%);
  animation: float 20s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(2deg); }
}

.hero-content {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  background: var(--primary-light);
  color: var(--primary-color);
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: 20px;
  font-size: var(--font-size-sm);
  font-weight: 500;
  margin-bottom: var(--spacing-lg);
}

.hero-title {
  font-size: var(--font-size-xxxl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-lg);
  line-height: 1.2;
}

.hero-subtitle {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
  line-height: 1.6;
}

.hero-actions {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
}


/* 按钮样式 */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-lg);
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.btn-large {
  padding: var(--spacing-lg) var(--spacing-xl);
  font-size: var(--font-size-md);
}

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

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-2);
}

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

.btn-secondary:hover {
  background: var(--bg-color-secondary);
  border-color: var(--border-level-2);
}

/* 功能区域 */
.features {
  padding: var(--spacing-xxl) 0;
  background: var(--bg-color-container);
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-xxl);
}

.section-header h2 {
  font-size: var(--font-size-xxl);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-md);
}

.section-header p {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
}

.feature-card {
  background: var(--bg-color-container);
  border: 1px solid var(--border-level-1);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  text-align: center;
  transition: all var(--transition-normal);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2);
  border-color: var(--primary-color);
}

.feature-icon {
  width: 64px;
  height: 64px;
  background: var(--primary-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--spacing-lg);
  font-size: 24px;
  color: var(--primary-color);
}

.feature-card h3 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-md);
}

.feature-card p {
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: var(--spacing-md);
}

/* 技术架构 */
.tech-stack {
  padding: var(--spacing-xxl) 0;
  background: var(--bg-color-page);
}

.tech-tabs {
  max-width: 1000px;
  margin: 0 auto;
}

.tab-nav {
  display: flex;
  justify-content: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-xl);
  border-bottom: 1px solid var(--border-level-1);
}

.tab-btn {
  padding: var(--spacing-md) var(--spacing-lg);
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.tab-btn:hover {
  color: var(--primary-color);
}

.tab-btn.active {
  color: var(--primary-color);
  border-bottom-color: var(--primary-color);
  font-weight: 500;
}

.tab-content {
  min-height: 400px;
}

.tab-pane {
  display: none;
}

.tab-pane.active {
  display: block;
}

/* 页脚 */
.footer {
  background: var(--bg-color-page);
  border-top: 1px solid var(--border-level-1);
  padding: var(--spacing-xxl) 0 var(--spacing-lg);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.footer-section.main-section .footer-logo {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.footer-section.main-section p {
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: var(--spacing-lg);
}

.footer-contact {
  margin-bottom: var(--spacing-lg);
}

.footer-contact .contact-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  color: var(--text-secondary);
  margin-bottom: var(--spacing-sm);
}

.footer-contact .contact-item i {
  width: 20px;
  color: var(--primary-color);
}

.social-links {
  display: flex;
  gap: var(--spacing-md);
}

.social-link {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--primary-light);
  color: var(--primary-color);
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.social-link:hover {
  background: var(--primary-color);
  color: white;
  transform: translateY(-2px);
}

.footer-section h4 {
  font-size: var(--font-size-md);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-lg);
}

.footer-section ul {
  list-style: none;
}

.footer-section li {
  margin-bottom: var(--spacing-sm);
}

.footer-section a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-section a:hover {
  color: var(--primary-color);
}

.footer-bottom {
  border-top: 1px solid var(--border-level-1);
  padding-top: var(--spacing-lg);
  text-align: center;
  color: var(--text-tertiary);
  font-size: var(--font-size-sm);
}

/* 功能展示区域 */
.features-showcase {
  padding: var(--spacing-xxl) 0;
  background: var(--bg-color-container);
}

.showcase-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(380px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xxl);
}

.showcase-item {
  background: var(--bg-color-container);
  border: 1px solid var(--border-level-1);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: all var(--transition-normal);
  position: relative;
  box-shadow: var(--shadow-1);
  animation: fadeInUp 0.6s ease-out;
  animation-fill-mode: both;
}

.showcase-item:nth-child(1) { animation-delay: 0.1s; }
.showcase-item:nth-child(2) { animation-delay: 0.2s; }
.showcase-item:nth-child(3) { animation-delay: 0.3s; }
.showcase-item:nth-child(4) { animation-delay: 0.4s; }
.showcase-item:nth-child(5) { animation-delay: 0.5s; }
.showcase-item:nth-child(6) { animation-delay: 0.6s; }

.showcase-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-normal);
}

.showcase-item:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-3);
  border-color: var(--primary-color);
}

.showcase-item:hover::before {
  transform: scaleX(1);
}

.showcase-image {
  width: 100%;
  height: 240px;
  overflow: hidden;
  background: var(--bg-color-secondary);
  position: relative;
}

.showcase-image::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(180deg, transparent 0%, rgba(0, 0, 0, 0.1) 100%);
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.showcase-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: all var(--transition-normal);
  filter: brightness(0.95);
}

.showcase-item:hover .showcase-image img {
  transform: scale(1.08);
  filter: brightness(1);
}

.showcase-item:hover .showcase-image::after {
  opacity: 1;
}

.showcase-content {
  padding: var(--spacing-xl);
  position: relative;
  z-index: 1;
  background: linear-gradient(135deg, var(--bg-color-container) 0%, rgba(0, 82, 217, 0.02) 100%);
}

.showcase-content h3 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.showcase-content h3::before {
  content: '';
  width: 4px;
  height: 20px;
  background: linear-gradient(180deg, var(--primary-color), var(--secondary-color));
  border-radius: 2px;
}

.showcase-content p {
  color: var(--text-secondary);
  line-height: 1.7;
  font-size: var(--font-size-md);
  margin-bottom: var(--spacing-md);
}

/* 实际应用案例 */
.use-cases {
  margin-top: var(--spacing-xxl);
}

.use-cases h3 {
  text-align: center;
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xl);
}

.use-case-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-lg);
}

.use-case-item {
  background: var(--bg-color-container);
  border: 1px solid var(--border-level-1);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-normal);
}

.use-case-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-2);
}

.use-case-image {
  width: 100%;
  height: 160px;
  overflow: hidden;
  background: var(--bg-color-secondary);
}

.use-case-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: all var(--transition-normal);
  filter: sepia(100%) hue-rotate(200deg) saturate(2) brightness(0.9);
}

.use-case-item:hover .use-case-image img {
  transform: scale(1.05);
  filter: sepia(100%) hue-rotate(200deg) saturate(2.5) brightness(1);
}

.use-case-content {
  padding: var(--spacing-md);
}

.use-case-content h4 {
  font-size: var(--font-size-md);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}

.use-case-content p {
  color: var(--text-secondary);
  line-height: 1.5;
  font-size: var(--font-size-sm);
}

/* 响应式设计 */
@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }
  
  .nav-right {
    display: none;
  }
  
  .hero-title {
    font-size: var(--font-size-xxl);
  }
  
  .hero-subtitle {
    font-size: var(--font-size-md);
  }
  
  .hero-actions {
    flex-direction: column;
    align-items: center;
  }
  
  .btn {
    width: 200px;
    justify-content: center;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }
  
  .features-grid {
    grid-template-columns: 1fr;
  }
  
  .showcase-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }
  
  .showcase-item {
    animation-delay: 0s !important;
  }
  
  .showcase-image {
    height: 200px;
  }
  
  .showcase-content {
    padding: var(--spacing-lg);
  }
  
  .showcase-content h3 {
    font-size: var(--font-size-lg);
  }
  
  .use-case-grid {
    grid-template-columns: 1fr;
  }
  
    
  .tab-nav {
    flex-wrap: wrap;
  }
}

/* 动画效果 */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}

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

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

::-webkit-scrollbar-thumb {
  background: var(--border-level-2);
  border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-tertiary);
}