/* ============================================================
   Lead Radar 官网样式
   纯 CSS，无外部依赖。设计令牌 + 组件 + 响应式。
   ============================================================ */

:root {
  --bg: #ffffff;
  --bg-alt: #f6f8fb;
  --bg-dark: #0f172a;
  --text: #1e293b;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  --brand: #e74c3c;          /* 小红书红 */
  --brand-dark: #c0392b;
  --brand-soft: #fdecea;
  --accent: #f97316;
  --gradient: linear-gradient(135deg, #e74c3c 0%, #f97316 100%);
  --border: #e2e8f0;
  --card: #ffffff;
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.06), 0 1px 2px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 8px 24px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 20px 50px rgba(15, 23, 42, 0.12);
  --radius: 14px;
  --radius-lg: 20px;
  --max-w: 1120px;
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 76px;
}

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--brand);
  text-decoration: none;
}

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

.container-narrow {
  max-width: 780px;
}

/* ---------------- 顶部导航 ---------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.7);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text);
  font-weight: 700;
  font-size: 18px;
}

.brand-mark {
  font-size: 20px;
}

.brand-badge {
  font-size: 11px;
  font-weight: 600;
  color: var(--brand);
  background: var(--brand-soft);
  border: 1px solid #fbd3cf;
  padding: 2px 8px;
  border-radius: 999px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-links a {
  color: var(--text-muted);
  font-size: 14.5px;
  font-weight: 500;
  transition: color 0.2s;
}

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

.nav-cta {
  color: #fff !important;
  background: var(--brand);
  padding: 8px 18px;
  border-radius: 999px;
  transition: background 0.2s;
}

.nav-cta:hover {
  background: var(--brand-dark);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.25s, opacity 0.25s;
}

/* ---------------- Hero ---------------- */

.hero {
  background:
    radial-gradient(900px 380px at 85% -10%, rgba(249, 115, 22, 0.12), transparent 60%),
    radial-gradient(700px 360px at 8% 0%, rgba(231, 76, 60, 0.10), transparent 60%);
  padding: 96px 0 88px;
  text-align: center;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--brand-dark);
  background: var(--brand-soft);
  border: 1px solid #fbd3cf;
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 24px;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--brand);
  animation: pulse 1.8s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.45; transform: scale(0.8); }
}

.hero-title {
  font-size: clamp(38px, 6vw, 60px);
  font-weight: 800;
  letter-spacing: -1px;
  line-height: 1.15;
  margin-bottom: 22px;
}

.gradient-text {
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.hero-sub {
  font-size: 17px;
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto 34px;
}

.hero-actions {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 34px;
}

.hero-note {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 14px;
  color: var(--text-muted);
}

.badge {
  display: inline-block;
  font-size: 12.5px;
  font-weight: 600;
  color: var(--accent);
  background: #fff4e6;
  border: 1px solid #fde3c3;
  padding: 4px 12px;
  border-radius: 999px;
}

/* ---------------- 通用区块 ---------------- */

.section {
  padding: 84px 0;
}

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

.section-head {
  text-align: center;
  margin-bottom: 52px;
}

.section-kicker {
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 2.5px;
  color: var(--brand);
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(26px, 4vw, 36px);
  font-weight: 800;
  letter-spacing: -0.5px;
  margin-bottom: 14px;
}

.section-desc {
  color: var(--text-muted);
  font-size: 16px;
  max-width: 560px;
  margin: 0 auto;
}

/* ---------------- 按钮 ---------------- */

.btn {
  display: inline-block;
  font-size: 15px;
  font-weight: 600;
  padding: 12px 26px;
  border-radius: 999px;
  transition: transform 0.18s, box-shadow 0.18s, background 0.18s;
  border: none;
  cursor: pointer;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  color: #fff;
  background: var(--brand);
  box-shadow: 0 10px 24px rgba(231, 76, 60, 0.28);
}

.btn-primary:hover {
  background: var(--brand-dark);
  box-shadow: 0 14px 30px rgba(231, 76, 60, 0.34);
}

.btn-ghost {
  color: var(--text);
  background: #fff;
  border: 1.5px solid var(--border);
}

.btn-ghost:hover {
  border-color: var(--brand);
  color: var(--brand);
}

.btn-outline {
  color: var(--brand);
  background: #fff;
  border: 1.5px solid var(--brand);
  width: 100%;
  text-align: center;
}

.btn-outline:hover {
  background: var(--brand-soft);
}

/* ---------------- 工作原理步骤 ---------------- */

.steps {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-bottom: 44px;
  counter-reset: step;
}

.step {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 24px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s, box-shadow 0.2s;
}

.step:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: var(--brand-soft);
  color: var(--brand);
  font-weight: 800;
  font-size: 14px;
  margin-bottom: 16px;
}

.step h3 {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 8px;
}

.step p {
  font-size: 14px;
  color: var(--text-muted);
}

.chips {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.chip {
  font-size: 13.5px;
  font-weight: 600;
  color: var(--text-muted);
  background: #fff;
  border: 1px solid var(--border);
  padding: 8px 16px;
  border-radius: 999px;
}

/* ---------------- 为什么选择 Lead Radar ---------------- */

.highlights-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
}

.highlight-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
  box-shadow: var(--shadow-sm);
}

.highlight-icon {
  font-size: 26px;
  display: inline-block;
  margin-bottom: 14px;
}

.highlight-card h3 {
  font-size: 16.5px;
  font-weight: 700;
  margin-bottom: 8px;
}

.highlight-card p {
  font-size: 14px;
  color: var(--text-muted);
}

/* ---------------- 定价卡片 ---------------- */

.plans {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  align-items: stretch;
  margin-bottom: 26px;
}

.plan {
  position: relative;
  display: flex;
  flex-direction: column;
  background: var(--card);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 30px 24px 26px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
}

.plan:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.plan-featured {
  border-color: var(--brand);
  box-shadow: var(--shadow-lg);
  background: linear-gradient(180deg, #fffdfd 0%, #fff 100%);
}

.plan-featured:hover {
  box-shadow: 0 24px 56px rgba(231, 76, 60, 0.22);
}

.plan-ribbon {
  position: absolute;
  top: -13px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--gradient);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  padding: 5px 16px;
  border-radius: 999px;
  box-shadow: 0 6px 14px rgba(231, 76, 60, 0.35);
  white-space: nowrap;
}

.plan-head {
  margin-bottom: 18px;
}

.plan-name {
  font-size: 20px;
  font-weight: 800;
  margin-bottom: 4px;
}

.plan-tag {
  font-size: 13px;
  color: var(--brand);
  font-weight: 600;
}

.plan-price {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-bottom: 10px;
}

.price-currency {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
}

.price-value {
  font-size: 42px;
  font-weight: 800;
  letter-spacing: -1px;
  line-height: 1;
}

.price-period {
  font-size: 14px;
  color: var(--text-muted);
}

.plan-desc {
  font-size: 13.5px;
  color: var(--text-muted);
  margin-bottom: 18px;
}

.plan-features {
  list-style: none;
  flex: 1;
  margin-bottom: 22px;
}

.plan-features li {
  position: relative;
  padding-left: 24px;
  font-size: 14px;
  color: var(--text);
  margin-bottom: 10px;
}

.plan-features li::before {
  content: "✓";
  position: absolute;
  left: 0;
  top: 0;
  color: var(--brand);
  font-weight: 700;
}

.pricing-note {
  text-align: center;
  font-size: 13.5px;
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto;
}

/* ---------------- FAQ ---------------- */

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0 20px;
  box-shadow: var(--shadow-sm);
  transition: border-color 0.2s;
}

.faq-item[open] {
  border-color: var(--brand);
}

.faq-item summary {
  cursor: pointer;
  list-style: none;
  font-size: 15.5px;
  font-weight: 600;
  padding: 18px 28px 18px 0;
  position: relative;
  outline: none;
}

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

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  font-size: 22px;
  font-weight: 400;
  color: var(--brand);
  transition: transform 0.2s;
}

.faq-item[open] summary::after {
  transform: translateY(-50%) rotate(45deg);
}

.faq-item p {
  font-size: 14.5px;
  color: var(--text-muted);
  padding-bottom: 18px;
}

/* ---------------- CTA ---------------- */

.section-cta {
  background:
    radial-gradient(720px 320px at 20% 0%, rgba(231, 76, 60, 0.14), transparent 60%),
    radial-gradient(720px 320px at 85% 100%, rgba(249, 115, 22, 0.14), transparent 60%);
}

.cta-box {
  text-align: center;
}

.cta-box h2 {
  font-size: clamp(28px, 4.5vw, 40px);
  font-weight: 800;
  letter-spacing: -0.5px;
  margin-bottom: 18px;
}

.cta-box p {
  font-size: 16px;
  color: var(--text-muted);
  max-width: 560px;
  margin: 0 auto 30px;
}

/* ---------------- Footer ---------------- */

.site-footer {
  background: var(--bg-dark);
  color: var(--text-light);
  padding: 48px 0 26px;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
  margin-bottom: 30px;
}

.footer-inner .brand-name {
  font-size: 17px;
  font-weight: 700;
  color: #fff;
}

.footer-note {
  font-size: 13px;
  margin-top: 6px;
}

.footer-links {
  display: flex;
  gap: 22px;
  list-style: none;
}

.footer-links a {
  color: var(--text-light);
  font-size: 13.5px;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: #fff;
}

.footer-copy {
  font-size: 12.5px;
  border-top: 1px solid rgba(148, 163, 184, 0.2);
  padding-top: 20px;
  text-align: center;
}

/* ---------------- 响应式 ---------------- */

@media (max-width: 960px) {
  .steps {
    grid-template-columns: repeat(2, 1fr);
  }

  .plans {
    grid-template-columns: repeat(2, 1fr);
    max-width: 640px;
    margin-left: auto;
    margin-right: auto;
  }
}

@media (max-width: 720px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    padding: 10px 24px 18px;
    display: none;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links li {
    width: 100%;
  }

  .nav-links a {
    display: block;
    padding: 12px 0;
    font-size: 16px;
  }

  .nav-cta {
    text-align: center;
    margin-top: 10px;
    color: #fff !important;
  }

  .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 {
    padding: 64px 0 60px;
  }

  .section {
    padding: 60px 0;
  }

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

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

  .plans {
    grid-template-columns: 1fr;
    max-width: 420px;
    margin-left: auto;
    margin-right: auto;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}