@import url('https://fonts.googleapis.com/css2?family=Nunito+Sans:wght@300;400;500;600;700&family=Rubik:wght@300;400;500;600;700&display=swap');

/* ============================================================
   CSS 自定义属性
   ============================================================ */
:root {
  --c-primary: #99ffcc;
  --c-accent: #00ff41;
  --c-dark: #001e3c;
  --c-dark-mid: #002a52;
  --c-dark-light: #003666;
  --c-text: #c8ffe8;
  --c-text-muted: #7ab8a0;
  --c-text-dim: #4a8070;
  --c-card-bg: #002040;
  --c-card-border: rgba(153, 255, 204, 0.12);
  --c-glow: rgba(0, 255, 65, 0.18);
  --r-card: 28px;
  --r-btn: 14px;
  --font-heading: 'Rubik', 'Nunito Sans', sans-serif;
  --font-body: 'Nunito Sans', 'Rubik', sans-serif;
  --nav-h: 100px;
  --max-w: 1200px;
  --prose-w: 780px;
  --trans-base: 240ms ease;
}

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

html {
  font-size: 17px;
  line-height: 1.65;
  scroll-behavior: smooth;
  background: var(--c-dark);
  color: var(--c-text);
}

body {
  font-family: var(--font-body);
  background: var(--c-dark);
  color: var(--c-text);
  min-height: 100vh;
  overflow-x: hidden;
}

img { display: block; max-width: 100%; height: auto; }
a { color: var(--c-primary); text-decoration: none; }
a:hover { color: var(--c-accent); }
p { margin-bottom: 1rem; }

/* ============================================================
   有机细胞底纹
   ============================================================ */
@keyframes breathing {
  0%, 100% { transform: scale(1); opacity: 0.35; }
  50% { transform: scale(1.06); opacity: 0.55; }
}

@keyframes pulse-glow {
  0%, 100% { opacity: 0.4; filter: blur(24px); }
  50% { opacity: 0.7; filter: blur(18px); }
}

@keyframes float-cell {
  0% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-12px) rotate(4deg); }
  100% { transform: translateY(0) rotate(0deg); }
}

@keyframes stagger-in {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* 点阵底纹 */
.dot-grid {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image:
    radial-gradient(circle, rgba(153,255,204,0.18) 1px, transparent 1px);
  background-size: 28px 28px;
}

/* 细胞形背景 */
.cell-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.cell-bg::before,
.cell-bg::after {
  content: '';
  position: absolute;
  border-radius: 60% 40% 70% 30% / 50% 60% 40% 50%;
  background: radial-gradient(ellipse at center, rgba(0,255,65,0.12), transparent 70%);
  animation: breathing 6s ease-in-out infinite, float-cell 10s ease-in-out infinite;
}

.cell-bg::before {
  width: 600px; height: 500px;
  top: -100px; right: -80px;
  animation-delay: 0s;
}

.cell-bg::after {
  width: 400px; height: 350px;
  bottom: -60px; left: -60px;
  animation-delay: 3s;
  background: radial-gradient(ellipse at center, rgba(153,255,204,0.10), transparent 70%);
}

/* hero blob */
.hero-blob {
  position: absolute;
  width: 480px; height: 420px;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  border-radius: 60% 40% 55% 45% / 45% 55% 45% 55%;
  background: radial-gradient(ellipse at 40% 40%, rgba(0,255,65,0.22), transparent 65%);
  animation: breathing 5s ease-in-out infinite, float-cell 8s ease-in-out infinite;
  pointer-events: none;
  z-index: 0;
}

/* ============================================================
   全局导航
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(0, 30, 60, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--c-card-border);
}

.brand-row {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0.75rem 1.5rem 0;
  display: flex;
  align-items: center;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--c-primary);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: 0.02em;
  text-decoration: none;
}

.brand-link:hover { color: var(--c-accent); }
.brand-mark { width: 28px; height: 28px; }
.brand-logo { height: 28px; width: auto; }
.brand-name { white-space: nowrap; }

.main-nav {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem 0.6rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 0;
  align-items: center;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  padding: 0.55rem 0.9rem;
  min-height: 42px;
  font-size: 0.88rem;
  font-family: var(--font-body);
  font-weight: 500;
  color: var(--c-text-muted);
  border-radius: 8px;
  transition: color var(--trans-base), background var(--trans-base);
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--c-primary);
  background: rgba(153, 255, 204, 0.08);
}

/* ============================================================
   布局框架
   ============================================================ */
main { width: 100%; }

.wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ============================================================
   Hero（首页）
   ============================================================ */
.hero-section {
  position: relative;
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 3rem;
  padding: 5rem 0 4rem;
  overflow: hidden;
}

.hero-media {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 400px;
}

.hero-img {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 520px;
  border-radius: 40px;
  object-fit: cover;
  aspect-ratio: 4/3;
  box-shadow: 0 0 60px rgba(0,255,65,0.2), 0 0 120px rgba(153,255,204,0.08);
  filter: saturate(1.1) contrast(1.02);
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: right;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 1.2rem;
}

.hero-eyebrow {
  display: inline-block;
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--c-accent);
  text-transform: uppercase;
  border: 1px solid rgba(0,255,65,0.3);
  padding: 0.3rem 0.8rem;
  border-radius: 999px;
  margin-bottom: 0;
}

.hero-h1 {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 4.5vw, 3.6rem);
  font-weight: 700;
  line-height: 1.15;
  color: var(--c-primary);
  letter-spacing: -0.02em;
}

.hero-lead {
  font-size: 1.05rem;
  color: var(--c-text-muted);
  max-width: 480px;
  line-height: 1.7;
  margin-bottom: 0;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: flex-end;
  flex-wrap: wrap;
}

/* ============================================================
   通用按钮
   ============================================================ */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.6rem;
  min-height: 46px;
  background: var(--c-accent);
  color: var(--c-dark);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.95rem;
  border-radius: var(--r-btn);
  text-decoration: none;
  transition: background var(--trans-base), transform var(--trans-base), box-shadow var(--trans-base);
  box-shadow: 0 0 20px rgba(0,255,65,0.35);
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.btn-primary:hover {
  background: var(--c-primary);
  transform: translateY(-2px);
  box-shadow: 0 0 32px rgba(0,255,65,0.5);
  color: var(--c-dark);
}

.btn-ghost {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.6rem;
  min-height: 46px;
  background: transparent;
  color: var(--c-primary);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: var(--r-btn);
  border: 1.5px solid rgba(153,255,204,0.4);
  text-decoration: none;
  transition: border-color var(--trans-base), color var(--trans-base), background var(--trans-base);
  white-space: nowrap;
}

.btn-ghost:hover {
  border-color: var(--c-accent);
  color: var(--c-accent);
  background: rgba(0,255,65,0.06);
}

/* ============================================================
   通用节段
   ============================================================ */
.section-title {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--c-primary);
  margin-bottom: 1.75rem;
  letter-spacing: -0.01em;
}

.content-section {
  padding: 3rem 0;
}

/* ============================================================
   卡片
   ============================================================ */
.card {
  background: var(--c-card-bg);
  border-radius: var(--r-card);
  border: 1px solid var(--c-card-border);
  overflow: hidden;
  transition: transform var(--trans-base), box-shadow var(--trans-base), border-color var(--trans-base);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0,0,0,0.4), 0 0 24px rgba(153,255,204,0.08);
  border-color: rgba(153,255,204,0.28);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.card-body {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.card-thumb {
  width: 100%;
  height: 180px;
  object-fit: cover;
}

.card-title {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--c-primary);
  display: block;
}

.card-desc {
  font-size: 0.9rem;
  color: var(--c-text-muted);
  line-height: 1.55;
  flex: 1;
}

.card-cta {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--c-accent);
  margin-top: 0.5rem;
}

.card-date {
  font-size: 0.8rem;
  color: var(--c-text-dim);
}

/* ============================================================
   子页链接组
   ============================================================ */
.sub-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.sub-link {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  padding: 1.1rem 1.5rem;
  min-height: 44px;
  background: var(--c-card-bg);
  border-radius: var(--r-card);
  border: 1px solid var(--c-card-border);
  text-decoration: none;
  flex: 1 1 220px;
  transition: border-color var(--trans-base), background var(--trans-base), transform var(--trans-base);
}

.sub-link:hover {
  border-color: rgba(153,255,204,0.3);
  background: rgba(0,32,64,0.9);
  transform: translateY(-2px);
}

.sub-link strong {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--c-primary);
}

.sub-link span {
  font-size: 0.83rem;
  color: var(--c-text-muted);
  line-height: 1.45;
}

/* ============================================================
   统计区块
   ============================================================ */
.stats-section {
  padding: 3rem 0;
  border-top: 1px solid var(--c-card-border);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.4rem;
  padding: 1.5rem 1rem;
  background: var(--c-card-bg);
  border-radius: var(--r-card);
  border: 1px solid var(--c-card-border);
  text-align: center;
}

.stat-num {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--c-accent);
  display: block;
  line-height: 1.1;
  animation: pulse-glow 4s ease-in-out infinite;
}

.stat-plus {
  font-size: 1.4rem;
  color: var(--c-primary);
}

.stat-label {
  font-size: 0.85rem;
  color: var(--c-text-muted);
  line-height: 1.4;
}

/* ============================================================
   功能页 Hero
   ============================================================ */
.feature-hero {
  position: relative;
  padding: 4rem 0 3rem;
  overflow: hidden;
}

.feature-hero-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 2rem;
  align-items: start;
  position: relative;
  z-index: 1;
}

.feature-hero-text {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.feature-hero-media {
  flex-shrink: 0;
}

.feature-hero-img {
  width: 320px;
  height: 220px;
  object-fit: cover;
  border-radius: 24px;
  box-shadow: 0 0 40px rgba(0,255,65,0.15);
}

.feature-h1 {
  font-family: var(--font-heading);
  font-size: clamp(1.6rem, 3.5vw, 2.8rem);
  font-weight: 700;
  color: var(--c-primary);
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.feature-lead {
  font-size: 1rem;
  color: var(--c-text-muted);
  max-width: 600px;
  line-height: 1.7;
  margin-bottom: 0;
}

/* ============================================================
   通用页面 Hero
   ============================================================ */
.page-hero {
  position: relative;
  padding: 4rem 0 3rem;
  overflow: hidden;
  border-bottom: 1px solid var(--c-card-border);
  margin-bottom: 0.5rem;
}

.page-hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  max-width: 700px;
}

.page-eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--c-accent);
  text-transform: uppercase;
  border-left: 3px solid var(--c-accent);
  padding-left: 0.7rem;
  margin-bottom: 0;
}

.page-h1 {
  font-family: var(--font-heading);
  font-size: clamp(1.6rem, 3.5vw, 2.6rem);
  font-weight: 700;
  color: var(--c-primary);
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.page-lead {
  font-size: 1rem;
  color: var(--c-text-muted);
  line-height: 1.7;
  max-width: 600px;
  margin-bottom: 0;
}

.page-date {
  font-size: 0.82rem;
  color: var(--c-text-dim);
  font-weight: 500;
}

/* ============================================================
   正文 prose
   ============================================================ */
.prose {
  max-width: var(--prose-w);
  color: var(--c-text);
  font-size: 1rem;
  line-height: 1.75;
}

.prose h2 {
  font-family: var(--font-heading);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--c-primary);
  margin: 2rem 0 0.8rem;
  letter-spacing: -0.01em;
}

.prose h3 {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--c-text);
  margin: 1.6rem 0 0.6rem;
}

.prose p { margin-bottom: 1rem; }

.prose ul, .prose ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

.prose li { margin-bottom: 0.4rem; }

.prose strong { color: var(--c-primary); font-weight: 700; }

.prose a {
  color: var(--c-accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

.prose blockquote {
  border-left: 3px solid var(--c-accent);
  padding-left: 1rem;
  color: var(--c-text-muted);
  font-style: italic;
  margin: 1.5rem 0;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.93rem;
}

.prose th {
  background: var(--c-dark-mid);
  color: var(--c-primary);
  padding: 0.6rem 1rem;
  text-align: left;
  font-weight: 600;
  border-bottom: 1px solid var(--c-card-border);
}

.prose td {
  padding: 0.55rem 1rem;
  border-bottom: 1px solid rgba(153,255,204,0.06);
  color: var(--c-text-muted);
}

.prose tr:hover td { background: rgba(153,255,204,0.03); }

/* ============================================================
   定价页
   ============================================================ */
.pricing-hero { margin-bottom: 1rem; }

.pricing-tiers-section { padding: 2.5rem 0; }

.pricing-tiers {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1.5rem;
  margin-bottom: 1rem;
}

.pricing-tier {
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  position: relative;
}

.tier-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--c-dark);
  background: var(--c-accent);
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  align-self: flex-start;
}

.tier-label {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--c-primary);
  display: block;
}

.tier-price {
  font-family: var(--font-heading);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--c-accent);
  line-height: 1.1;
}

.tier-desc {
  font-size: 0.88rem;
  color: var(--c-text-muted);
  line-height: 1.55;
  margin-bottom: 0;
}

.pricing-cta-row {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  padding: 2rem 0;
}

/* ============================================================
   FAQ 页
   ============================================================ */
.faq-prose { max-width: var(--prose-w); }

.faq-bottom-nav,
.privacy-bottom-nav,
.about-cta-row,
.feature-nav-cta,
.contact-bottom-nav {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  padding: 2rem 0;
}

.related-section {
  padding: 2.5rem 0;
  border-top: 1px solid var(--c-card-border);
}

/* ============================================================
   关于页
   ============================================================ */
.about-hero {
  position: relative;
  padding: 4rem 0 3rem;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 2rem;
  align-items: center;
  overflow: hidden;
  border-bottom: 1px solid var(--c-card-border);
}

.about-hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}

.about-hero-media { flex-shrink: 0; z-index: 1; }

.about-img {
  width: 300px;
  height: 200px;
  object-fit: cover;
  border-radius: 24px;
  box-shadow: 0 0 40px rgba(153,255,204,0.12);
}

.about-values {
  padding: 3rem 0;
}

.values-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1.25rem;
}

.value-item {
  padding: 1.5rem;
  background: var(--c-card-bg);
  border-radius: var(--r-card);
  border: 1px solid var(--c-card-border);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  transition: border-color var(--trans-base);
}

.value-item:hover { border-color: rgba(153,255,204,0.28); }

.value-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  color: var(--c-primary);
  display: block;
}

.value-desc {
  font-size: 0.88rem;
  color: var(--c-text-muted);
  line-height: 1.55;
  margin-bottom: 0;
}

/* ============================================================
   联系页
   ============================================================ */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1.5rem;
  margin-top: 0.5rem;
}

.contact-card {
  padding: 1.75rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.contact-type {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--c-primary);
  display: block;
}

.contact-info {
  font-size: 0.9rem;
  color: var(--c-text-muted);
  line-height: 1.6;
  margin-bottom: 0;
}

.contact-cards { padding: 2.5rem 0; }

/* ============================================================
   同级页面侧边
   ============================================================ */
.siblings-aside {
  padding: 2rem 0;
  border-top: 1px solid var(--c-card-border);
}

.aside-title {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--c-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 1rem;
}

.sib-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.sib-link {
  display: inline-flex;
  align-items: center;
  padding: 0.55rem 1rem;
  min-height: 42px;
  background: var(--c-card-bg);
  border-radius: 10px;
  border: 1px solid var(--c-card-border);
  font-size: 0.88rem;
  color: var(--c-text-muted);
  text-decoration: none;
  transition: color var(--trans-base), border-color var(--trans-base);
}

.sib-link:hover {
  color: var(--c-primary);
  border-color: rgba(153,255,204,0.25);
}

/* ============================================================
   子页卡片区
   ============================================================ */
.children-section { padding: 2.5rem 0; }

/* ============================================================
   首页特色功能区
   ============================================================ */
.features-section { padding: 3rem 0; }
.home-content { padding: 3rem 0; }
.sub-pages-section { padding: 2rem 0; }

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  background: var(--c-dark-mid);
  border-top: 1px solid var(--c-card-border);
  margin-top: 4rem;
}

.footer-cta-block {
  background: linear-gradient(135deg, rgba(0,255,65,0.12) 0%, rgba(153,255,204,0.06) 100%);
  border-bottom: 1px solid var(--c-card-border);
  padding: 3rem 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.25rem;
  text-align: center;
}

.footer-cta-text {
  font-family: var(--font-heading);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--c-primary);
  margin-bottom: 0;
}

.footer-cols {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2.5rem 1.5rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-col-title {
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--c-accent);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 0.4rem;
}

.footer-col a {
  font-size: 0.9rem;
  color: var(--c-text-muted);
  padding: 0.25rem 0;
  min-height: 36px;
  display: inline-flex;
  align-items: center;
  transition: color var(--trans-base);
}

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

.footer-bottom {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 1.25rem 1.5rem;
  border-top: 1px solid var(--c-card-border);
  text-align: center;
}

.footer-bottom p {
  font-size: 0.8rem;
  color: var(--c-text-dim);
  margin-bottom: 0;
  line-height: 1.6;
}

/* ============================================================
   动画控制（stagger）
   ============================================================ */
.card, .sub-link, .value-item, .stat-item, .pricing-tier, .contact-card {
  animation: stagger-in 0.5s ease both;
}

.card:nth-child(2), .sub-link:nth-child(2), .value-item:nth-child(2), .stat-item:nth-child(2), .pricing-tier:nth-child(2), .contact-card:nth-child(2) { animation-delay: 0.06s; }
.card:nth-child(3), .sub-link:nth-child(3), .value-item:nth-child(3), .stat-item:nth-child(3), .pricing-tier:nth-child(3), .contact-card:nth-child(3) { animation-delay: 0.12s; }
.card:nth-child(4), .sub-link:nth-child(4), .value-item:nth-child(4), .stat-item:nth-child(4), .pricing-tier:nth-child(4) { animation-delay: 0.18s; }
.card:nth-child(5), .sub-link:nth-child(5) { animation-delay: 0.24s; }
.card:nth-child(6), .sub-link:nth-child(6) { animation-delay: 0.30s; }

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

/* ============================================================
   响应式 — 平板
   ============================================================ */
@media (max-width: 900px) {
  .hero-section {
    grid-template-columns: 1fr;
    min-height: auto;
    padding: 3rem 0;
    text-align: center;
  }

  .hero-content {
    text-align: center;
    align-items: center;
    order: -1;
  }

  .hero-actions { justify-content: center; }

  .hero-media { min-height: 260px; }

  .hero-img { max-width: 400px; }

  .feature-hero-inner { grid-template-columns: 1fr; }
  .feature-hero-media { display: none; }

  .about-hero { grid-template-columns: 1fr; }
  .about-hero-media { display: none; }

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

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

/* ============================================================
   响应式 — 手机（375px+）
   ============================================================ */
@media (max-width: 600px) {
  :root { --nav-h: auto; }

  html { font-size: 16px; }

  .brand-row { padding: 0.6rem 1rem 0; }

  .main-nav {
    padding: 0 1rem 0.5rem;
    gap: 0.15rem 0;
  }

  .nav-link {
    font-size: 0.82rem;
    padding: 0.5rem 0.65rem;
    min-height: 42px;
  }

  .wrap { padding: 0 1rem; }

  .hero-section { padding: 2.5rem 0; gap: 2rem; }

  .hero-h1 { font-size: 1.75rem; }

  .hero-img { max-width: 100%; border-radius: 24px; }

  .hero-blob { width: 280px; height: 240px; }

  .hero-actions { flex-direction: column; align-items: center; }

  .btn-primary, .btn-ghost {
    width: 100%;
    max-width: 320px;
    justify-content: center;
    min-height: 48px;
    font-size: 1rem;
  }

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

  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 0.75rem; }

  .stat-num { font-size: 1.5rem; }

  .pricing-tiers { grid-template-columns: 1fr 1fr; gap: 0.75rem; }

  .pricing-tier { padding: 1.25rem 1rem; }

  .pricing-cta-row, .faq-bottom-nav, .privacy-bottom-nav,
  .about-cta-row, .feature-nav-cta, .contact-bottom-nav {
    flex-direction: column;
  }

  .footer-cta-block { padding: 2rem 1rem; }

  .footer-cols { grid-template-columns: 1fr; gap: 1.5rem; padding: 2rem 1rem; }

  .footer-col a { min-height: 42px; }

  .sub-links { flex-direction: column; }
  .sub-link { flex: none; }

  .values-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }

  .page-hero { padding: 2.5rem 0 2rem; }
  .feature-hero { padding: 2.5rem 0 2rem; }
  .about-hero { padding: 2.5rem 0 2rem; }
  .about-values { padding: 2rem 0; }

  .section-title { font-size: 1.25rem; }

  .page-h1 { font-size: 1.5rem; }
  .feature-h1 { font-size: 1.5rem; }

  .sib-links { flex-direction: column; }
  .sib-link { width: 100%; }
}