/* ==========================================================================
   糖果云 (TangGuoYun) - 原生浅色极速样式表 (Light Theme Pure CSS)
   ========================================================================== */

:root {
  --bg-main: #eaeef4;
  --bg-card: #ffffff;
  --bg-subtle: #dbe1e8;
  --text-primary: #0b192c;
  --text-secondary: #1e293b;
  --text-muted: #475569;
  
  --primary-pink: #ff4e88;
  --primary-purple: #6c5ce7;
  --primary-cyan: #06b6d4;
  
  --gradient-candy: linear-gradient(135deg, #ff4e88 0%, #6c5ce7 100%);
  --gradient-candy-hover: linear-gradient(135deg, #f03a74 0%, #5b4bc4 100%);
  --gradient-subtle: linear-gradient(180deg, #ffffff 0%, #eaeef4 100%);
  --gradient-hero-bg: radial-gradient(circle at 50% 0%, rgba(255, 78, 136, 0.14) 0%, rgba(108, 92, 231, 0.10) 45%, #eaeef4 100%);
  
  --border-light: #cbd5e1;
  --border-active: #94a3b8;
  
  --shadow-sm: 0 3px 8px rgba(15, 23, 42, 0.07);
  --shadow-md: 0 12px 28px -5px rgba(108, 92, 231, 0.12), 0 8px 12px -6px rgba(15, 23, 42, 0.06);
  --shadow-lg: 0 22px 40px -10px rgba(255, 78, 136, 0.18), 0 12px 22px -3px rgba(15, 23, 42, 0.08);
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

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

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

/* 统一布局容器 */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* 通用按钮规范 (CTA) */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  border: none;
  text-align: center;
  white-space: nowrap;
}

.btn-primary {
  background: var(--gradient-candy);
  color: #ffffff !important;
  box-shadow: 0 4px 15px rgba(255, 78, 136, 0.35);
}

.btn-primary:hover {
  background: var(--gradient-candy-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 22px rgba(255, 78, 136, 0.45);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary) !important;
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background: var(--bg-subtle);
  border-color: var(--border-active);
  transform: translateY(-2px);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.125rem;
}

/* 导航栏 */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(234, 238, 244, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.4rem;
  font-weight: 800;
  background: var(--gradient-candy);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: -0.5px;
}

.nav-logo-img {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  object-fit: cover;
  box-shadow: 0 4px 12px rgba(255, 78, 136, 0.25);
  border: 1px solid rgba(255, 255, 255, 0.9);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 600;
  color: #1e293b;
  transition: color 0.2s;
}

.nav-link:hover {
  color: #be185d;
}

.nav-cta {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* 主视觉 Hero 区域 */
.hero {
  position: relative;
  padding: 90px 0 60px;
  background: var(--gradient-hero-bg);
  overflow: hidden;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 18px;
  background: rgba(190, 24, 93, 0.08);
  border: 1px solid rgba(190, 24, 93, 0.22);
  border-radius: var(--radius-full);
  color: #be185d;
  font-size: 0.875rem;
  font-weight: 700;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 3.2rem;
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -1px;
  margin-bottom: 20px;
  color: #0f172a;
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, #1e1b4b 0%, #5b21b6 50%, #be185d 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-weight: 900;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: #334155;
  font-weight: 500;
  max-width: 760px;
  margin: 0 auto 36px;
  line-height: 1.75;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 40px;
}

/* 首页 AI 美图展台卡片 */
.hero-image-wrapper {
  max-width: 620px;
  margin: 0 auto 50px;
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 20px 40px -15px rgba(108, 92, 231, 0.22), 0 10px 20px -5px rgba(15, 23, 42, 0.08);
  border: 4px solid #ffffff;
  background: var(--bg-card);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.hero-image-wrapper:hover {
  transform: translateY(-4px);
  box-shadow: 0 25px 50px -12px rgba(255, 78, 136, 0.28);
}

.hero-candy-img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
  max-height: 400px;
}

.hero-image-caption {
  padding: 12px 20px;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  color: var(--text-primary);
  font-size: 0.925rem;
  font-weight: 700;
  border-top: 1px solid var(--border-light);
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  max-width: 960px;
  margin: 0 auto;
  padding: 28px;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

.metric-item {
  text-align: center;
}

.metric-value {
  font-size: 2rem;
  font-weight: 800;
  color: var(--primary-purple);
  line-height: 1.1;
  margin-bottom: 6px;
}

.metric-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* 区块通用标题 */
.section {
  padding: 80px 0;
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 50px;
}

.section-tag {
  text-transform: uppercase;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 1px;
  color: var(--primary-pink);
  margin-bottom: 10px;
  display: block;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 14px;
  line-height: 1.3;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
}

/* 核心优势卡片 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  padding: 32px 24px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
  transition: all 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(108, 92, 231, 0.3);
}

.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: rgba(108, 92, 231, 0.08);
  color: var(--primary-purple);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.feature-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.feature-desc {
  font-size: 0.925rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* 流媒体与 AI 支持 */
.ecosystem-section {
  background: var(--bg-subtle);
  border-top: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
}

.eco-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}

.eco-card {
  background: var(--bg-card);
  padding: 36px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
}

.eco-card-title {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 20px;
}

.eco-card-title svg {
  color: var(--primary-pink);
}

.eco-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.eco-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 18px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-primary);
  transition: all 0.2s;
}

.eco-tag:hover {
  border-color: var(--primary-purple);
  background: #ffffff;
  color: var(--primary-purple);
}

/* 套餐价格对比 */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.pricing-card {
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
  transition: all 0.3s ease;
}

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

.pricing-card.popular {
  border: 2px solid var(--primary-pink);
  box-shadow: var(--shadow-lg);
}

.popular-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--gradient-candy);
  color: #ffffff;
  padding: 4px 18px;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.5px;
}

.plan-name {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.plan-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.plan-price {
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 24px;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.plan-price span {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.plan-features {
  margin-bottom: 32px;
  flex-grow: 1;
}

.plan-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.plan-features svg {
  color: var(--primary-purple);
  flex-shrink: 0;
}

/* 用户评价 */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  padding: 32px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
}

.review-stars {
  color: #f59e0b;
  display: flex;
  gap: 4px;
  margin-bottom: 16px;
}

.review-text {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.author-avatar {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-full);
  background: var(--gradient-candy);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.95rem;
}

.author-info h4 {
  font-size: 0.95rem;
  font-weight: 700;
}

.author-info p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* 常见问题 FAQ (纯 CSS 手风琴) */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.faq-item summary {
  padding: 20px 24px;
  font-size: 1.05rem;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "+";
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--primary-pink);
  transition: transform 0.2s;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-answer {
  padding: 0 24px 20px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
  border-top: 1px solid var(--bg-subtle);
  padding-top: 16px;
}

/* 页脚 - 严格规则：仅保留 4 个标题，在新标签页打开 */
.footer {
  background: #ffffff;
  border-top: 1px solid var(--border-light);
  padding: 40px 0;
  text-align: center;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  margin-bottom: 24px;
}

.footer-link {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-secondary);
  transition: color 0.2s;
}

.footer-link:hover {
  color: var(--primary-pink);
}

.footer-copyright {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* 子页面内容框架 (about / terms / privacy / sitemap) */
.page-header {
  background: var(--gradient-hero-bg);
  padding: 60px 0 40px;
  text-align: center;
  border-bottom: 1px solid var(--border-light);
}

.page-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.page-content {
  padding: 60px 0;
}

.content-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow-sm);
  line-height: 1.8;
}

.content-card h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 28px 0 14px;
  color: var(--text-primary);
}

.content-card h2:first-child {
  margin-top: 0;
}

.content-card p {
  color: var(--text-secondary);
  margin-bottom: 16px;
}

.content-card ul {
  list-style: disc;
  padding-left: 24px;
  margin-bottom: 16px;
  color: var(--text-secondary);
}

.content-card li {
  margin-bottom: 8px;
}

/* 移动端响应式 (@media) */
@media (max-width: 992px) {
  .hero-title { font-size: 2.5rem; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .pricing-grid { grid-template-columns: 1fr; max-width: 500px; margin: 0 auto; }
  .reviews-grid { grid-template-columns: 1fr; }
  .articles-grid { grid-template-columns: 1fr !important; }
  .hero-metrics { grid-template-columns: repeat(2, 1fr); gap: 20px; }
}

@media (max-width: 768px) {
  .nav-menu { display: none; } /* 移动端隐藏冗余菜单，保留品牌与极速 CTA */
  .hero { padding: 50px 0 40px; }
  .hero-title { font-size: 2rem; }
  .hero-subtitle { font-size: 1rem; }
  .hero-actions { flex-direction: column; width: 100%; }
  .hero-actions .btn { width: 100%; }
  
  .features-grid { grid-template-columns: 1fr; }
  .eco-grid { grid-template-columns: 1fr; }
  .articles-grid { grid-template-columns: 1fr !important; }
  
  .footer-nav { flex-direction: column; gap: 18px; }
  .content-card { padding: 24px; }
}