/**
 * 招个AI 品牌官网视觉规范 V2.0
 * 基于Logo深蓝主色调：#0A1628 到 #1B365D 渐变
 * 风格：企业级、科技感、专业可信
 * 更新：2026-03-25
 */

/* ========================================
   1. 设计令牌 - CSS Variables
   ======================================== */

:root {
  /* 主品牌色 - Logo深蓝体系 */
  --primary-deep: #0A1628;           /* 深邃背景 */
  --primary-dark: #1B365D;           /* Logo主深蓝 */
  --primary: #2563EB;                /* 交互蓝 */
  --primary-light: #3B82F6;          /* 高亮 */
  --primary-lighter: #60A5FA;        /* 轻亮 */
  
  /* 渐变定义 */
  --gradient-primary: linear-gradient(135deg, #0A1628 0%, #1B365D 50%, #2563EB 100%);
  --gradient-hero: linear-gradient(135deg, #0A1628 0%, #1B365D 100%);
  --gradient-card: linear-gradient(145deg, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0.05) 100%);
  --gradient-glow: radial-gradient(ellipse at center, rgba(37, 99, 235, 0.3) 0%, transparent 70%);
  
  /* 背景系统 */
  --bg-dark: #0A1628;
  --bg-navy: #1B365D;
  --bg-slate: #1E293B;
  --bg-light: #F8FAFC;
  --bg-white: #FFFFFF;
  --bg-card: rgba(255, 255, 255, 0.95);
  --bg-glass: rgba(255, 255, 255, 0.08);
  
  /* 文字色彩 */
  --text-heading: #0F172A;
  --text-body: #334155;
  --text-muted: #64748B;
  --text-light: #94A3B8;
  --text-on-dark: #FFFFFF;
  --text-on-dark-muted: rgba(255, 255, 255, 0.7);
  
  /* 功能色 */
  --success: #10B981;
  --warning: #F59E0B;
  --danger: #EF4444;
  --info: #3B82F6;
  
  /* 边框 */
  --border-light: rgba(226, 232, 240, 0.8);
  --border-dark: rgba(255, 255, 255, 0.1);
  
  /* 阴影系统 - 专业级 */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  --shadow-glow: 0 0 40px rgba(37, 99, 235, 0.3);
  --shadow-dark: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
  
  /* 圆角 */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-2xl: 32px;
  --radius-full: 9999px;
  
  /* 间距系统 - 8px基准 */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-10: 40px;
  --space-12: 48px;
  --space-16: 64px;
  --space-20: 80px;
  --space-24: 96px;
  --space-32: 128px;
  
  /* 布局 */
  --content-max: 1280px;
  --content-padding: 24px;
  --navbar-height: 80px;
  
  /* 过渡动画 */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========================================
   2. 基础样式 Reset
   ======================================== */

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-body);
  background-color: var(--bg-light);
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

/* ========================================
   3. 布局组件
   ======================================== */

.container {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--content-padding);
}

.section {
  padding: var(--space-24) 0;
  position: relative;
}

.section-dark {
  background: var(--gradient-primary);
  color: var(--text-on-dark);
}

.section-light {
  background: var(--bg-light);
}

.section-white {
  background: var(--bg-white);
}

/* ========================================
   4. 导航栏 - 深色科技风
   ======================================== */

.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--navbar-height);
  background: rgba(10, 22, 40, 0.95);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-dark);
}

.navbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--content-padding);
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.navbar-logo {
  height: 40px;
  width: auto;
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.navbar-link {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-on-dark-muted);
  padding: var(--space-2) 0;
  position: relative;
  transition: color var(--transition-fast);
}

.navbar-link:hover {
  color: var(--text-on-dark);
}

.navbar-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width var(--transition-base);
}

.navbar-link:hover::after {
  width: 100%;
}

/* ========================================
   5. 按钮系统
   ======================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.5;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-base);
  white-space: nowrap;
}

.btn-primary {
  background: var(--primary);
  color: white;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.4);
}

.btn-primary:hover {
  background: var(--primary-light);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.5);
}

.btn-secondary {
  background: transparent;
  color: white;
  border: 1.5px solid rgba(255, 255, 255, 0.3);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.5);
}

.btn-white {
  background: white;
  color: var(--primary-dark);
  box-shadow: var(--shadow-md);
}

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

.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: 16px;
  border-radius: var(--radius-lg);
}

/* ========================================
   6. Hero 区域 - 全新设计
   ======================================== */

.hero {
  min-height: 100vh;
  padding-top: var(--navbar-height);
  background: var(--gradient-hero);
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(ellipse 80% 50% at 20% 40%, rgba(37, 99, 235, 0.15) 0%, transparent 50%),
    radial-gradient(ellipse 60% 40% at 80% 60%, rgba(59, 130, 246, 0.1) 0%, transparent 50%);
  pointer-events: none;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-16);
  align-items: center;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--content-padding);
  width: 100%;
  position: relative;
  z-index: 1;
}

.hero-content {
  max-width: 600px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(37, 99, 235, 0.2);
  border: 1px solid rgba(37, 99, 235, 0.3);
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 500;
  color: var(--primary-lighter);
  margin-bottom: var(--space-6);
}

.hero-badge-dot {
  width: 8px;
  height: 8px;
  background: var(--success);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.hero-title {
  font-size: 56px;
  font-weight: 800;
  line-height: 1.1;
  color: var(--text-on-dark);
  margin-bottom: var(--space-6);
  letter-spacing: -0.02em;
}

.hero-title span {
  background: linear-gradient(135deg, #60A5FA 0%, #3B82F6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 20px;
  line-height: 1.7;
  color: var(--text-on-dark-muted);
  margin-bottom: var(--space-8);
}

.hero-buttons {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}

.hero-stats {
  display: flex;
  gap: var(--space-8);
  margin-top: var(--space-12);
  padding-top: var(--space-8);
  border-top: 1px solid var(--border-dark);
}

.hero-stat {
  display: flex;
  flex-direction: column;
}

.hero-stat-value {
  font-size: 32px;
  font-weight: 700;
  color: var(--text-on-dark);
}

.hero-stat-label {
  font-size: 14px;
  color: var(--text-on-dark-muted);
}

.hero-visual {
  position: relative;
}

.hero-image-wrapper {
  position: relative;
  border-radius: var(--radius-2xl);
  overflow: hidden;
  box-shadow: var(--shadow-dark);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.hero-image-wrapper::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(180deg, transparent 60%, rgba(10, 22, 40, 0.8) 100%);
  z-index: 1;
  pointer-events: none;
}

.hero-image {
  width: 100%;
  height: auto;
  display: block;
}

/* ========================================
   7. Section 标题组件
   ======================================== */

.section-header {
  text-align: center;
  max-width: 800px;
  margin: 0 auto var(--space-16);
}

.section-header-left {
  text-align: left;
  margin-left: 0;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(37, 99, 235, 0.1);
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: var(--space-4);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.section-title {
  font-size: 42px;
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-heading);
  margin-bottom: var(--space-4);
  letter-spacing: -0.01em;
}

.section-desc {
  font-size: 18px;
  line-height: 1.7;
  color: var(--text-muted);
}

.section-dark .section-title {
  color: var(--text-on-dark);
}

.section-dark .section-desc {
  color: var(--text-on-dark-muted);
}

/* ========================================
   8. 特性卡片 - 玻璃拟态风格
   ======================================== */

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.feature-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
  border-color: rgba(37, 99, 235, 0.2);
}

.feature-card:hover::before {
  transform: scaleX(1);
}

.feature-icon {
  width: 64px;
  height: 64px;
  background: var(--gradient-primary);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  margin-bottom: var(--space-5);
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.3);
}

.feature-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: var(--space-3);
}

.feature-desc {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-muted);
}

/* ========================================
   9. 解决方案 - 左右交替布局
   ======================================== */

.solutions-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-20);
}

.solution-item {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: center;
}

.solution-item:nth-child(even) {
  direction: rtl;
}

.solution-item:nth-child(even) > * {
  direction: ltr;
}

.solution-visual {
  position: relative;
  border-radius: var(--radius-2xl);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
}

.solution-visual img {
  width: 100%;
  height: auto;
}

.solution-number {
  font-size: 14px;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-3);
}

.solution-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: var(--space-4);
  line-height: 1.3;
}

.solution-desc {
  font-size: 17px;
  line-height: 1.7;
  color: var(--text-muted);
  margin-bottom: var(--space-6);
}

.solution-features {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.solution-feature {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: 15px;
  color: var(--text-body);
}

.solution-feature svg {
  width: 20px;
  height: 20px;
  color: var(--success);
  flex-shrink: 0;
}

/* ========================================
   10. 定价卡片
   ======================================== */

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
  max-width: 1100px;
  margin: 0 auto;
}

.pricing-card {
  background: var(--bg-white);
  border: 2px solid var(--border-light);
  border-radius: var(--radius-2xl);
  padding: var(--space-8);
  position: relative;
  transition: all var(--transition-base);
}

.pricing-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.pricing-card.featured {
  border-color: var(--primary);
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.05) 0%, white 100%);
  transform: scale(1.02);
}

.pricing-card.featured::before {
  content: '推荐';
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: white;
  font-size: 13px;
  font-weight: 600;
  padding: var(--space-1) var(--space-4);
  border-radius: var(--radius-full);
}

.pricing-header {
  text-align: center;
  margin-bottom: var(--space-6);
  padding-bottom: var(--space-6);
  border-bottom: 1px solid var(--border-light);
}

.pricing-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: var(--space-2);
}

.pricing-price {
  font-size: 48px;
  font-weight: 800;
  color: var(--text-heading);
  line-height: 1;
}

.pricing-price span {
  font-size: 16px;
  font-weight: 400;
  color: var(--text-muted);
}

.pricing-desc {
  font-size: 14px;
  color: var(--text-muted);
  margin-top: var(--space-2);
}

.pricing-features {
  margin-bottom: var(--space-8);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.pricing-feature {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: 15px;
  color: var(--text-body);
}

.pricing-feature svg {
  width: 20px;
  height: 20px;
  color: var(--success);
  flex-shrink: 0;
}

/* ========================================
   11. CTA 区域
   ======================================== */

.cta-section {
  background: var(--gradient-primary);
  padding: var(--space-24) 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-section::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  right: -50%;
  bottom: -50%;
  background: radial-gradient(ellipse at center, rgba(37, 99, 235, 0.2) 0%, transparent 70%);
  pointer-events: none;
}

.cta-content {
  position: relative;
  z-index: 1;
  max-width: 700px;
  margin: 0 auto;
}

.cta-title {
  font-size: 42px;
  font-weight: 700;
  color: var(--text-on-dark);
  margin-bottom: var(--space-5);
}

.cta-desc {
  font-size: 18px;
  color: var(--text-on-dark-muted);
  margin-bottom: var(--space-8);
}

.cta-buttons {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
  flex-wrap: wrap;
}

/* ========================================
   12. Footer
   ======================================== */

.footer {
  background: var(--bg-dark);
  color: var(--text-on-dark-muted);
  padding: var(--space-16) 0 var(--space-8);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

.footer-brand {
  max-width: 300px;
}

.footer-logo {
  height: 40px;
  margin-bottom: var(--space-4);
}

.footer-desc {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: var(--space-4);
}

.footer-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-on-dark);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-4);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer-link {
  font-size: 14px;
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--text-on-dark);
}

.footer-bottom {
  padding-top: var(--space-8);
  border-top: 1px solid var(--border-dark);
  text-align: center;
  font-size: 14px;
}

/* ========================================
   13. 响应式设计
   ======================================== */

@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: var(--space-10);
    text-align: center;
  }
  
  .hero-content {
    max-width: 100%;
  }
  
  .hero-title {
    font-size: 42px;
  }
  
  .hero-stats {
    justify-content: center;
  }
  
  .hero-visual {
    order: -1;
    max-width: 600px;
    margin: 0 auto;
  }
  
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .solution-item {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }
  
  .solution-item:nth-child(even) {
    direction: ltr;
  }
  
  .solution-visual {
    order: -1;
  }
  
  .pricing-grid {
    grid-template-columns: 1fr;
    max-width: 400px;
  }
  
  .pricing-card.featured {
    transform: none;
  }
  
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --navbar-height: 64px;
    --content-padding: 16px;
  }
  
  .navbar-nav {
    display: none;
  }
  
  .hero-title {
    font-size: 32px;
  }
  
  .hero-subtitle {
    font-size: 16px;
  }
  
  .hero-buttons {
    flex-direction: column;
  }
  
  .hero-buttons .btn {
    width: 100%;
  }
  
  .hero-stats {
    flex-direction: column;
    gap: var(--space-4);
  }
  
  .section {
    padding: var(--space-16) 0;
  }
  
  .section-title {
    font-size: 28px;
  }
  
  .features-grid {
    grid-template-columns: 1fr;
  }
  
  .feature-card {
    text-align: center;
  }
  
  .feature-icon {
    margin: 0 auto var(--space-4);
  }
  
  .solution-title {
    font-size: 24px;
  }
  
  .cta-title {
    font-size: 28px;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }
  
  .footer-brand {
    max-width: 100%;
    text-align: center;
  }
}

/* ========================================
   14. 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 forwards;
}

/* 滚动显示动画 */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s ease-out;
}

.reveal.active {
  opacity: 1;
  transform: translateY(0);
}