/* ========================================
   照颖科技官网 - 商务风格全局样式 v1.1
   遵循 DESIGN.md v1.0 规范
   ======================================== */

:root {
  /* 主色调 - 商务深蓝 */
  --primary: #1E3A5F;
  --primary-light: #2C5282;
  --primary-dark: #152A45;

  /* 辅助色 - 稳重金色 */
  --accent: #B8860B;
  --accent-light: #DAA520;
  --accent-light2: #F5DEB3;

  /* 三频段色 - 温和版本 */
  --survival: #C53030;
  --relationship: #2B6CB0;
  --meaning: #6B46C1;

  /* 中性色 */
  --bg-light: #F8F9FA;
  --bg-white: #FFFFFF;
  --text-dark: #1A202C;
  --text-gray: #4A5568;
  --text-light: #718096;
  --border: #E2E8F0;

  /* 渐变 - 稳重商务 */
  --gradient-primary: linear-gradient(135deg, #1E3A5F 0%, #2C5282 100%);
  --gradient-hero: linear-gradient(135deg, #1E3A5F 0%, #2C5282 50%, #1E3A5F 100%);
  --gradient-gold: linear-gradient(135deg, #B8860B 0%, #DAA520 100%);

  /* 阴影 */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 30px rgba(0,0,0,0.12);
  --shadow-card: 0 2px 8px rgba(0,0,0,0.08);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 14px;
  color: var(--text-dark);
  background: var(--bg-white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ========================================
   导航栏 - 参考全频谱学术网风格
   ======================================== */
.header {
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav a {
  color: var(--text-gray);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9rem;
  padding: 0.5rem 0;
  transition: color 0.2s;
  position: relative;
}

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

.nav a.active {
  color: var(--primary);
  font-weight: 600;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-dark);
  flex-shrink: 0;
}

.logo:hover {
  text-decoration: none;
  opacity: 1;
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: var(--gradient-primary);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 16px;
  flex-shrink: 0;
  box-shadow: 0 2px 8px rgba(30,58,95,0.3);
}

.logo-text {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.logo-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-dark);
  line-height: 1.2;
  letter-spacing: 1px;
}

.logo-tagline {
  font-size: 9px;
  color: var(--text-gray);
  letter-spacing: 2px;
  font-weight: 500;
  text-transform: uppercase;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--text-gray);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9rem;
  padding: 0.5rem 0;
  transition: color 0.2s;
}

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

.nav-links a.active {
  color: var(--primary);
  font-weight: 600;
}

.nav-links a::after {
  display: none;
}

.nav-external {
  color: var(--primary) !important;
  font-weight: 600 !important;
  border: 1px solid var(--primary);
  padding: 0.4rem 0.8rem !important;
  border-radius: 4px;
  transition: all 0.2s;
}

.nav-external:hover {
  background: var(--primary) !important;
  color: white !important;
}

.nav-external::after {
  display: none !important;
}

.nav-cta {
  background: var(--primary) !important;
  color: white !important;
  padding: 0.5rem 1rem !important;
  border-radius: 6px !important;
  font-weight: 600 !important;
  transition: all 0.2s !important;
}

.nav-cta:hover {
  background: var(--primary-light) !important;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.nav-cta::after {
  display: none !important;
}

/* ========================================
   子导航栏
   ======================================== */
.sub-nav {
  position: fixed;
  top: 68px;
  left: 0;
  right: 0;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  z-index: 999;
}

.sub-nav .container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  overflow-x: auto;
}

.sub-nav a {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 1rem 1.25rem;
  color: var(--text-gray);
  font-size: 0.9rem;
  font-weight: 500;
  white-space: nowrap;
  border-bottom: 3px solid transparent;
  transition: all 0.2s;
  text-decoration: none;
}

.sub-nav a:hover {
  color: var(--primary);
  background: rgba(30, 58, 95, 0.03);
}

.sub-nav a.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
  font-weight: 600;
}

.sub-nav-icon {
  font-size: 1rem;
}

/* 有子导航栏的页面 */
body.has-subnav {
  padding-top: 116px;
}

/* ========================================
   Hero 区域 - 商务稳重
   ======================================== */
.hero {
  padding: 5rem 2rem 4rem;
  background: var(--gradient-hero);
  color: white;
  text-align: center;
}

.hero-content {
  max-width: 900px;
  margin: 0 auto;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: 1.25rem;
  line-height: 1.25;
  letter-spacing: -1px;
}

.hero h1 span {
  color: var(--accent-light);
}

.hero p {
  font-size: 1rem;
  opacity: 0.9;
  margin-bottom: 2rem;
  line-height: 1.7;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.85rem 1.75rem;
  border-radius: 6px;
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  transition: all 0.25s;
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--accent);
  color: white;
  box-shadow: 0 2px 8px rgba(184, 134, 11, 0.3);
}

.btn-primary:hover {
  background: var(--accent-light);
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(184, 134, 11, 0.4);
}

.btn-secondary {
  background: rgba(255,255,255,0.1);
  color: white;
  border: 1px solid rgba(255,255,255,0.3);
}

.btn-secondary:hover {
  background: rgba(255,255,255,0.2);
  border-color: rgba(255,255,255,0.5);
}

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

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

.hero-stats {
  margin-top: 3.5rem;
  display: flex;
  justify-content: center;
  gap: 4rem;
}

.hero-stat {
  text-align: center;
}

.hero-stat-number {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--accent-light);
}

.hero-stat-label {
  font-size: 0.875rem;
  opacity: 0.85;
  margin-top: 0.25rem;
}

/* ========================================
   通用容器
   ======================================== */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 2rem;
}

.section {
  padding: 5rem 2rem;
}

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

.section-title {
  text-align: center;
  margin-bottom: 3rem;
}

.section-title h2 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 0.75rem;
}

.section-title p {
  color: var(--text-gray);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
}

/* ========================================
   产品卡片
   ======================================== */
.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.product-card {
  background: var(--bg-white);
  border-radius: 12px;
  padding: 2rem;
  box-shadow: var(--shadow-card);
  border: 1px solid var(--border);
  transition: transform 0.25s, box-shadow 0.25s;
}

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

.product-icon {
  width: 56px;
  height: 56px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
  margin-bottom: 1.25rem;
}

.product-icon.ccri {
  background: rgba(107, 70, 193, 0.1);
}

.product-icon.ai-scan {
  background: rgba(184, 134, 11, 0.1);
}

.product-icon.fshi {
  background: rgba(43, 108, 176, 0.1);
}

.product-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--text-dark);
}

.product-card p {
  color: var(--text-gray);
  margin-bottom: 1.25rem;
  font-size: 0.95rem;
  line-height: 1.7;
}

.product-features {
  list-style: none;
  margin-bottom: 1.5rem;
}

.product-features li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-gray);
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

.product-features li::before {
  content: '✓';
  color: var(--primary);
  font-weight: 700;
}

.product-price {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.price-tag {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
}

.price-unit {
  color: var(--text-light);
  font-size: 0.875rem;
}

.price-free {
  color: #2F855A;
  font-weight: 700;
  font-size: 1.2rem;
}

/* ========================================
   课程卡片
   ======================================== */
.courses-section {
  background: var(--bg-light);
}

.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 2rem;
}

.course-card {
  background: var(--bg-white);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: var(--shadow-card);
  border: 1px solid var(--border);
  transition: transform 0.25s, box-shadow 0.25s;
}

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

.course-header {
  padding: 1.75rem 2rem;
  color: white;
}

.course-header.basic {
  background: linear-gradient(135deg, #2C5282 0%, #3182CE 100%);
}

.course-header.tuner {
  background: linear-gradient(135deg, #276749 0%, #38A169 100%);
}

.course-header.ethics {
  background: linear-gradient(135deg, #553C9A 0%, #805AD5 100%);
}

.course-badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  background: rgba(255,255,255,0.2);
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.course-header h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.course-header p {
  opacity: 0.9;
  font-size: 0.9rem;
}

.course-body {
  padding: 2rem;
}

.course-price {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.course-price-main {
  font-size: 2rem;
  font-weight: 800;
  color: var(--text-dark);
}

.course-price-sub {
  color: var(--text-gray);
  font-size: 0.875rem;
}

.course-features {
  list-style: none;
  margin-bottom: 1.5rem;
}

.course-features li {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  color: var(--text-gray);
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}

.course-features li::before {
  content: '✓';
  color: var(--primary);
  font-weight: 700;
  flex-shrink: 0;
}

.course-cta {
  width: 100%;
  justify-content: center;
}

/* ========================================
   企业服务卡片
   ======================================== */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.service-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2rem;
  text-align: center;
  transition: all 0.25s;
}

.service-card:hover {
  border-color: var(--primary-light);
  box-shadow: var(--shadow-md);
}

.service-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 1.25rem;
  background: var(--gradient-primary);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
}

.service-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--text-dark);
}

.service-card p {
  color: var(--text-gray);
  font-size: 0.9rem;
  margin-bottom: 1.25rem;
}

.service-price {
  color: var(--text-light);
  font-size: 0.85rem;
  margin-bottom: 1rem;
}

/* ========================================
   为什么选择
   ======================================== */
.why-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
}

.why-item {
  text-align: center;
  padding: 1.5rem;
}

.why-icon {
  width: 60px;
  height: 60px;
  margin: 0 auto 1rem;
  background: var(--bg-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.why-item h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--text-dark);
}

.why-item p {
  color: var(--text-gray);
  font-size: 0.9rem;
}

/* ========================================
   页脚
   ======================================== */
.footer {
  background: #0f172a;
  color: #cbd5e1;
  padding: 4rem 2rem 2rem;
}

.footer-content {
  max-width: 1280px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
}

.footer-brand .logo {
  margin-bottom: 1rem;
}

.footer-brand .logo-name {
  color: #ffffff;
}

.footer-brand .logo-tagline {
  color: #94a3b8;
}

.footer-brand p {
  color: #94a3b8;
  font-size: 0.9rem;
  line-height: 1.7;
}

.footer-column h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: white;
}

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

.footer-column li {
  margin-bottom: 0.75rem;
}

.footer-column a {
  color: var(--text-light);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s;
}

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

/* Footer - 备选类名 */
.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.footer-col h4 {
  font-size: 0.9rem;
  font-weight: 600;
  color: white;
  margin-bottom: 1rem;
}

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

.footer-col li {
  margin-bottom: 0.5rem;
}

.footer-col a {
  color: var(--text-light);
  text-decoration: none;
  font-size: 0.85rem;
  transition: color 0.2s;
}

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

.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 0.75rem;
}

.footer-logo-icon {
  width: 36px;
  height: 36px;
  background: var(--gradient-primary);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 600;
  font-size: 1rem;
}

.footer-logo span {
  font-size: 1.1rem;
  font-weight: 600;
  color: white;
}

.footer-bottom {
  max-width: 1280px;
  margin: 3rem auto 0;
  padding-top: 2rem;
  border-top: 1px solid rgba(255,255,255,0.08);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  gap: 0.5rem;
  font-size: 13px;
  color: #64748b;
}

/* ========================================
   页面特定样式
   ======================================== */
.page-header {
  padding: 8rem 2rem 4rem;
  background: var(--gradient-hero);
  color: white;
  text-align: center;
}

.page-header h1 {
  font-size: 2.25rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.page-header p {
  font-size: 1.1rem;
  opacity: 0.92;
  max-width: 600px;
  margin: 0 auto;
}

/* ========================================
   CTA Banner
   ======================================== */
.cta-banner {
  background: var(--gradient-primary);
  color: white;
  text-align: center;
  padding: 4rem 2rem;
}

.cta-banner h2 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
}

.cta-banner p {
  opacity: 0.92;
  margin-bottom: 2rem;
  font-size: 1.1rem;
}

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

.cta-banner .btn-primary:hover {
  background: var(--bg-light);
}

/* ========================================
   三频段指示器
   ======================================== */
.frequency-bars {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin: 2rem 0;
}

.frequency-bar {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.frequency-label {
  width: 80px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-gray);
}

.frequency-track {
  flex: 1;
  height: 10px;
  background: var(--bg-light);
  border-radius: 5px;
  overflow: hidden;
}

.frequency-fill {
  height: 100%;
  border-radius: 5px;
  transition: width 0.5s ease;
}

.frequency-fill.survival {
  background: var(--survival);
}

.frequency-fill.relationship {
  background: var(--relationship);
}

.frequency-fill.meaning {
  background: var(--meaning);
}

.frequency-value {
  width: 40px;
  text-align: right;
  font-weight: 700;
  color: var(--text-dark);
}

/* ========================================
   定价卡片
   ======================================== */
.pricing-card {
  background: var(--bg-white);
  border-radius: 12px;
  padding: 2.5rem;
  box-shadow: var(--shadow-card);
  border: 1px solid var(--border);
  text-align: center;
}

.pricing-card.featured {
  border: 2px solid var(--primary);
  position: relative;
}

.pricing-card.featured::before {
  content: '推荐';
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent);
  color: white;
  padding: 0.25rem 1rem;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 700;
}

.pricing-card h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.pricing-amount {
  font-size: 2.75rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

.pricing-amount span {
  font-size: 1rem;
  font-weight: 400;
  color: var(--text-gray);
}

.pricing-note {
  color: var(--text-light);
  font-size: 0.85rem;
  margin-bottom: 2rem;
}

/* ========================================
   隐私保证
   ======================================== */
.privacy-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background: #F0FFF4;
  color: #276749;
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 500;
  border: 1px solid #C6F6D5;
}

/* ========================================
   响应式
   ======================================== */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 2rem;
  }

  .hero p {
    font-size: 1rem;
  }

  .hero-stats {
    gap: 2rem;
  }

  .nav-links {
    display: none;
  }

  .section-title h2 {
    font-size: 1.75rem;
  }

  .services-grid {
    grid-template-columns: 1fr;
  }

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

  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
  }
}


/* ========================================
   课程页FAQ问答区块
   ======================================== */

.faq-section {
  max-width: 800px;
  margin: 5rem auto 0;
  padding: 3rem 2rem;
  border-top: 1px solid rgba(255,255,255,0.1);
}

.faq-title {
  text-align: center;
  font-size: 1.8rem;
  font-weight: 700;
  color: #e2e8f0;
  margin-bottom: 2.5rem;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.faq-item {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 12px;
  padding: 2rem;
}

.faq-item h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: #e2e8f0;
  margin-bottom: 1rem;
  line-height: 1.6;
}

.faq-item p {
  font-size: 0.95rem;
  color: #94a3b8;
  line-height: 1.8;
  margin-bottom: 0.75rem;
}

.faq-item ul {
  padding-left: 1.5rem;
  margin-bottom: 0.75rem;
}

.faq-item li {
  font-size: 0.95rem;
  color: #94a3b8;
  line-height: 1.8;
  margin-bottom: 0.25rem;
}

.faq-highlight {
  background: rgba(167, 139, 250, 0.1);
  border-left: 3px solid #a78bfa;
  padding: 0.75rem 1rem;
  border-radius: 0 8px 8px 0;
  color: #c4b5fd !important;
}

@media (max-width: 768px) {
  .faq-section {
    margin-top: 3rem;
    padding: 2rem 1.25rem;
  }
  .faq-item {
    padding: 1.25rem;
  }
}