/* ============================================
   AI智能获客助手 · 宣传网站样式
   主色：翡翠绿（#0fbf7f 系）
   ============================================ */

:root {
  --primary: #0fbf7f;
  --primary-dark: #0a9963;
  --primary-light: #e6f9f1;
  --ink: #12211b;
  --ink-2: #3d4f47;
  --ink-3: #6b7d74;
  --bg: #ffffff;
  --bg-alt: #f4faf7;
  --bg-dark: #0d1f18;
  --bg-dark-2: #12291f;
  --line: #e3ece7;
  --radius: 16px;
  --radius-lg: 24px;
  --shadow: 0 4px 24px rgba(18, 33, 27, 0.07);
  --shadow-lg: 0 12px 40px rgba(18, 33, 27, 0.12);
  --font:
    "PingFang SC", "Microsoft YaHei", "Segoe UI", "Helvetica Neue", Arial,
    sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}
.container-narrow {
  max-width: 820px;
}

img {
  max-width: 100%;
}
a {
  color: inherit;
  text-decoration: none;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 22px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all 0.25s ease;
  white-space: nowrap;
}
.btn-lg {
  padding: 14px 32px;
  font-size: 16px;
}
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  box-shadow: 0 6px 20px rgba(15, 191, 127, 0.35);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 26px rgba(15, 191, 127, 0.45);
}
.btn-ghost {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.35);
  color: #fff;
  backdrop-filter: blur(4px);
}
.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.18);
}
.btn-light {
  background: #fff;
  color: var(--primary-dark);
}
.btn-light:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 26px rgba(0, 0, 0, 0.2);
}
.btn-outline-light {
  border-color: rgba(255, 255, 255, 0.6);
  color: #fff;
}
.btn-outline-light:hover {
  background: rgba(255, 255, 255, 0.12);
}

/* ---------- 导航 ---------- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(13, 31, 24, 0.75);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  transition: background 0.3s;
}
.nav-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  height: 64px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 17px;
  color: #fff;
}
.logo-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: linear-gradient(135deg, var(--primary), #0aa86e);
  font-size: 16px;
  box-shadow: 0 3px 10px rgba(15, 191, 127, 0.4);
}
.nav-links {
  display: flex;
  gap: 4px;
  margin-left: auto;
}
.nav-links a {
  color: rgba(255, 255, 255, 0.78);
  font-size: 14px;
  padding: 7px 12px;
  border-radius: 8px;
  transition: all 0.2s;
}
.nav-links a:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.1);
}
.nav-cta {
  padding: 8px 18px;
  font-size: 14px;
}
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  margin-left: auto;
}
.nav-toggle span {
  width: 22px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: all 0.3s;
}
.nav-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle.open span:nth-child(2) {
  opacity: 0;
}
.nav-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: 150px 0 90px;
  color: #fff;
  overflow: hidden;
  background: var(--bg-dark);
}
.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(
      700px 420px at 15% 0%,
      rgba(15, 191, 127, 0.28),
      transparent 60%
    ),
    radial-gradient(
      600px 400px at 90% 20%,
      rgba(10, 153, 99, 0.22),
      transparent 60%
    ),
    radial-gradient(
      500px 380px at 60% 100%,
      rgba(15, 191, 127, 0.12),
      transparent 60%
    ),
    linear-gradient(180deg, #0d1f18 0%, #0f2a1f 100%);
}
.hero-inner {
  position: relative;
  text-align: center;
}
.hero-badge {
  display: inline-block;
  padding: 7px 18px;
  border-radius: 999px;
  background: rgba(15, 191, 127, 0.14);
  border: 1px solid rgba(15, 191, 127, 0.4);
  color: #7ee8bd;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 26px;
}
.hero h1 {
  font-size: 56px;
  line-height: 1.18;
  font-weight: 800;
  letter-spacing: 1px;
  margin-bottom: 22px;
}
.grad-text {
  background: linear-gradient(120deg, #34e39e, #7ee8bd 55%, #b6f5da);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-sub {
  font-size: 17px;
  color: rgba(255, 255, 255, 0.75);
  max-width: 640px;
  margin: 0 auto 34px;
}
.hero-sub strong {
  color: #7ee8bd;
  font-weight: 600;
}
.hero-actions {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}
.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 760px;
  margin: 64px auto 0;
}
.stat {
  padding: 20px 12px;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
}
.stat-num {
  font-size: 34px;
  font-weight: 800;
  color: #34e39e;
}
.stat-num span {
  font-size: 16px;
  font-weight: 600;
  margin-left: 2px;
}
.stat-label {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
  margin-top: 4px;
}

/* ---------- 通用 Section ---------- */
.section {
  padding: 92px 0;
}
.section-alt {
  background: var(--bg-alt);
}
.section-dark {
  background: linear-gradient(180deg, var(--bg-dark), var(--bg-dark-2));
  color: #fff;
}
.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 56px;
}
.section-tag {
  display: inline-block;
  padding: 5px 16px;
  border-radius: 999px;
  background: var(--primary-light);
  color: var(--primary-dark);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 2px;
  margin-bottom: 16px;
}
.section-tag.light {
  background: rgba(15, 191, 127, 0.16);
  color: #7ee8bd;
}
.section-head h2 {
  font-size: 36px;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 14px;
}
.section-head p {
  color: var(--ink-3);
  font-size: 16px;
}
.section-dark .section-head p {
  color: rgba(255, 255, 255, 0.65);
}

/* ---------- 痛点 ---------- */
.pain-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.pain-card {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 24px;
  box-shadow: var(--shadow);
  transition:
    transform 0.25s,
    box-shadow 0.25s;
}
.pain-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.pain-icon {
  font-size: 30px;
  margin-bottom: 12px;
}
.pain-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}
.pain-card p {
  font-size: 14px;
  color: var(--ink-3);
  margin-bottom: 14px;
}
.pain-fix {
  font-size: 13.5px;
  font-weight: 600;
  color: var(--primary-dark);
  background: var(--primary-light);
  border-radius: 10px;
  padding: 9px 12px;
}

/* ---------- 核心能力 ---------- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.feature-card {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 32px 26px;
  box-shadow: var(--shadow);
  transition:
    transform 0.25s,
    box-shadow 0.25s,
    border-color 0.25s;
}
.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(15, 191, 127, 0.45);
}
.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 54px;
  height: 54px;
  border-radius: 15px;
  background: var(--primary-light);
  font-size: 26px;
  margin-bottom: 18px;
}
.feature-card h3 {
  font-size: 19px;
  margin-bottom: 10px;
}
.feature-card > p {
  font-size: 14px;
  color: var(--ink-3);
  margin-bottom: 16px;
}
.feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 7px;
}
.feature-list li {
  font-size: 13.5px;
  color: var(--ink-2);
  padding-left: 22px;
  position: relative;
}
.feature-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

/* ---------- 获客闭环 ---------- */
.loop-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 48px;
}
.loop-card {
  position: relative;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 22px 26px;
  box-shadow: var(--shadow);
  overflow: hidden;
  transition:
    transform 0.25s,
    box-shadow 0.25s;
}
.loop-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.loop-step {
  position: absolute;
  top: 10px;
  right: 16px;
  font-size: 44px;
  font-weight: 800;
  color: var(--primary-light);
  line-height: 1;
}
.loop-icon {
  font-size: 28px;
  margin-bottom: 12px;
}
.loop-card h3 {
  font-size: 17px;
  margin-bottom: 8px;
}
.loop-card p {
  font-size: 13.5px;
  color: var(--ink-3);
}
.loop-flow {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
  padding: 22px;
  border-radius: var(--radius-lg);
  background: var(--primary-light);
}
.flow-node {
  padding: 9px 20px;
  border-radius: 999px;
  background: #fff;
  color: var(--primary-dark);
  font-weight: 700;
  font-size: 14px;
  box-shadow: 0 2px 10px rgba(15, 191, 127, 0.18);
}
.flow-arrow {
  color: var(--primary);
  font-size: 20px;
  font-weight: 700;
}

/* ---------- 优势 ---------- */
.why-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.why-card {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  padding: 30px 26px;
  transition:
    transform 0.25s,
    background 0.25s,
    border-color 0.25s;
}
.why-card:hover {
  transform: translateY(-4px);
  background: rgba(15, 191, 127, 0.09);
  border-color: rgba(15, 191, 127, 0.4);
}
.why-icon {
  font-size: 30px;
  margin-bottom: 14px;
}
.why-card h3 {
  font-size: 18px;
  margin-bottom: 10px;
  color: #eafff5;
}
.why-card p {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.65);
}

/* ---------- 适用对象 ---------- */
.audience-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}
.audience-card {
  text-align: center;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 34px 22px;
  box-shadow: var(--shadow);
  transition:
    transform 0.25s,
    box-shadow 0.25s,
    border-color 0.25s;
}
.audience-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(15, 191, 127, 0.45);
}
.audience-icon {
  font-size: 40px;
  margin-bottom: 14px;
}
.audience-card h3 {
  font-size: 17px;
  margin-bottom: 8px;
}
.audience-card p {
  font-size: 13.5px;
  color: var(--ink-3);
}

/* ---------- FAQ ---------- */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.faq-item {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition:
    border-color 0.25s,
    box-shadow 0.25s;
}
.faq-item.open {
  border-color: rgba(15, 191, 127, 0.5);
  box-shadow: var(--shadow);
}
.faq-q {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 19px 24px;
  background: none;
  border: none;
  font-family: inherit;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  cursor: pointer;
  text-align: left;
}
.faq-arrow {
  flex-shrink: 0;
  width: 26px;
  height: 26px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--primary-light);
  color: var(--primary-dark);
  font-size: 16px;
  font-weight: 700;
  transition: transform 0.3s;
}
.faq-item.open .faq-arrow {
  transform: rotate(45deg);
}
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
}
.faq-a p {
  padding: 0 24px 20px;
  font-size: 14.5px;
  color: var(--ink-3);
}

/* ---------- CTA ---------- */
.cta {
  padding: 96px 0;
  background:
    radial-gradient(
      600px 300px at 20% 20%,
      rgba(255, 255, 255, 0.12),
      transparent 60%
    ),
    linear-gradient(135deg, var(--primary), var(--primary-dark));
}
.cta-inner {
  text-align: center;
  color: #fff;
}
.cta h2 {
  font-size: 36px;
  font-weight: 800;
  margin-bottom: 14px;
}
.cta p {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 32px;
}

/* ---------- Footer ---------- */
.footer {
  background: var(--bg-dark);
  color: rgba(255, 255, 255, 0.7);
}
.footer-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 40px;
  padding: 60px 24px 44px;
}
.footer-brand .logo-text {
  color: #fff;
  font-weight: 700;
  font-size: 17px;
}
.footer-brand p {
  margin-top: 14px;
  font-size: 13.5px;
  color: rgba(255, 255, 255, 0.55);
}
.footer-col {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.footer-col h4 {
  color: #fff;
  font-size: 15px;
  margin-bottom: 6px;
}
.footer-col a {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.6);
  transition: color 0.2s;
  width: fit-content;
}
.footer-col a:hover {
  color: #7ee8bd;
}
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding: 20px 24px;
  text-align: center;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.45);
}

/* ---------- 回到顶部 ---------- */
.back-top {
  position: fixed;
  right: 26px;
  bottom: 26px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: none;
  background: var(--primary);
  color: #fff;
  font-size: 20px;
  cursor: pointer;
  box-shadow: 0 6px 20px rgba(15, 191, 127, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all 0.3s;
  z-index: 90;
}
.back-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.back-top:hover {
  background: var(--primary-dark);
}

/* ---------- 滚动动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition:
    opacity 0.6s ease,
    transform 0.6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .hero h1 {
    font-size: 44px;
  }
  .pain-grid,
  .feature-grid,
  .why-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .loop-grid,
  .audience-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero-stats {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(13, 31, 24, 0.97);
    padding: 16px 24px 24px;
    gap: 6px;
    transform: translateY(-130%);
    transition: transform 0.3s ease;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  }
  .nav-links.open {
    transform: translateY(0);
  }
  .nav-links a {
    padding: 12px;
    font-size: 15px;
  }
  .nav-toggle {
    display: flex;
  }
  .nav-cta {
    display: none;
  }

  .hero {
    padding: 120px 0 70px;
  }
  .hero h1 {
    font-size: 34px;
  }
  .hero-sub {
    font-size: 15px;
  }
  .section {
    padding: 64px 0;
  }
  .section-head h2 {
    font-size: 27px;
  }
  .cta h2 {
    font-size: 27px;
  }

  .pain-grid,
  .feature-grid,
  .why-grid,
  .loop-grid,
  .audience-grid,
  .hero-stats {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 28px;
  }
  .loop-flow {
    gap: 8px;
  }
  .flow-arrow {
    display: none;
  }
}