/* ==========================================================================
   SupaNexus 中文首页样式（精简版：仅业务介绍，无超链接）
   依据 whale-ui/design-by-claude-v2.pen 中「Landing Page Chinese」（1440 宽）
   与「SupaNexus Mobile — Light」（390 宽）两个画板实现。
   设计 token 直接映射为 CSS 自定义属性，见 :root。
   ========================================================================== */

:root {
  --brand: #1212f9;
  --bg-light: #ffffff;
  --bg-muted: #f8f8fc;
  --text-primary: #0a0a0f;
  --text-secondary: #6b6b7b;
  --text-white: #ffffff;
  --border: #e4e4ef;
  --card-bg: #f4f4fc;
  --icon-box-bg: #e8e8ff;
  --brand-tint: rgba(18, 18, 249, 0.125);
  --brand-tint-border: rgba(18, 18, 249, 0.25);

  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue",
    Arial, sans-serif;

  --container: 1440px;
  --gutter: 64px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.5;
  color: var(--text-primary);
  background: var(--bg-light);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1,
h2,
h3,
p {
  margin: 0;
}

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

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

/* --------------------------------------------------------------------------
   通用元素
   -------------------------------------------------------------------------- */

.eyebrow {
  color: var(--brand);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1.5px;
  line-height: 1.4;
}

.section-title {
  font-size: 42px;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

.section-subtitle {
  color: var(--text-secondary);
  font-size: 16px;
  line-height: 1.6;
}

.section-stack {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 48px;
}

.section-stack-lg {
  gap: 56px;
}

.section-header {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 12px;
  max-width: 560px;
}

.section-header-wide {
  max-width: 700px;
}

.icon {
  width: 1em;
  height: 1em;
  flex-shrink: 0;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  fill: none;
}

.icon-box {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--icon-box-bg);
  color: var(--brand);
  border-radius: 10px;
  flex-shrink: 0;
}

.icon-box-sm {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: var(--brand-tint);
  font-size: 16px;
}

.card-grid {
  display: grid;
  gap: 20px;
  width: 100%;
  list-style: none;
  margin: 0;
  padding: 0;
}

.card-grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

/* --------------------------------------------------------------------------
   导航（仅品牌标识）
   -------------------------------------------------------------------------- */

.nav {
  background: var(--bg-light);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  height: 72px;
  display: flex;
  align-items: center;
}

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

.logo-mark {
  width: 28px;
  height: 28px;
  border-radius: 6px;
}

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

.hero {
  padding: 96px 0 80px;
  text-align: center;
}

.hero-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 32px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border: 1px solid var(--border);
  border-radius: 20px;
  background: var(--card-bg);
  color: var(--text-secondary);
  font-size: 12px;
  font-weight: 500;
  line-height: 1.4;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand);
}

.hero-title {
  font-size: 72px;
  font-weight: 800;
  line-height: 1.45;
  letter-spacing: -0.015em;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.hero-title .accent {
  color: var(--brand);
  font-style: normal;
}

.hero-subtitle {
  max-width: 620px;
  color: var(--text-secondary);
  font-size: 18px;
  line-height: 1.6;
}

.hero-note {
  color: var(--text-secondary);
  font-size: 13px;
}

/* --------------------------------------------------------------------------
   功能特性
   -------------------------------------------------------------------------- */

.features {
  padding: 80px 0;
}

.feature-card {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 28px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--card-bg);
}

.feature-card .icon-box {
  width: 44px;
  height: 44px;
  font-size: 20px;
}

.feature-card h3 {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.45;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   真实模型 / 定价方式：编号要点三列
   -------------------------------------------------------------------------- */

.real {
  background: var(--bg-muted);
  padding: 80px 0;
}

.pricing {
  padding: 80px 0;
}

.point-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 32px 40px;
  width: 100%;
  max-width: 1200px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.point {
  display: flex;
  gap: 16px;
}

.num-box {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  background: var(--brand-tint);
  border: 1px solid var(--brand-tint-border);
  color: var(--brand);
  font-size: 11px;
  font-weight: 700;
}

.point h3 {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.45;
  margin-bottom: 4px;
}

.point p {
  color: var(--text-secondary);
  font-size: 13px;
  line-height: 1.55;
}

/* --------------------------------------------------------------------------
   零数据留存
   -------------------------------------------------------------------------- */

.privacy {
  background: var(--bg-muted);
  padding: 80px 0;
}

.privacy .section-title {
  font-size: 40px;
}

.privacy-card {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 24px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-light);
}

.privacy-card .icon-box {
  width: 40px;
  height: 40px;
  font-size: 18px;
}

.privacy-card h3 {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.45;
}

.privacy-card p {
  color: var(--text-secondary);
  font-size: 13px;
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   三步上手
   -------------------------------------------------------------------------- */

.steps {
  padding: 80px 0;
}

.steps-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  width: 100%;
  list-style: none;
  margin: 0;
  padding: 0;
}

.step {
  display: flex;
  flex-direction: column;
  gap: 20px;
  padding: 40px 36px;
  background: var(--bg-light);
}

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

.step-head {
  display: flex;
  align-items: center;
  gap: 16px;
  color: var(--text-secondary);
  font-size: 22px;
}

.step-circle {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--brand);
  color: var(--text-white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 800;
}

.step h3 {
  font-size: 20px;
  font-weight: 700;
  line-height: 1.45;
}

.step p {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   常见问题
   -------------------------------------------------------------------------- */

.faq {
  background: var(--bg-muted);
  padding: 80px 0;
}

.faq-inner {
  display: flex;
  align-items: flex-start;
  gap: 64px;
}

.faq-left {
  flex: 0 0 360px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-left .section-title {
  font-size: 36px;
}

.faq-left .section-subtitle {
  max-width: 340px;
  font-size: 15px;
}

.faq-list {
  flex: 1 1 auto;
  min-width: 0;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-light);
  overflow: hidden;
}

.faq-item {
  padding: 20px 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.faq-item + .faq-item {
  border-top: 1px solid var(--border);
}

.faq-item h3 {
  font-size: 14px;
  font-weight: 600;
  line-height: 1.45;
}

.faq-item p {
  color: var(--text-secondary);
  font-size: 13px;
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   页脚
   -------------------------------------------------------------------------- */

.footer {
  background: var(--bg-muted);
  padding: 64px 0 40px;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.footer-brand .logo {
  font-size: 16px;
}

.footer-brand .logo-mark {
  width: 24px;
  height: 24px;
  border-radius: 5px;
}

.footer-tagline {
  max-width: 260px;
  color: var(--text-secondary);
  font-size: 13px;
  line-height: 1.6;
}

.footer-bottom {
  margin-top: 48px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  color: var(--text-secondary);
  font-size: 12px;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 16px;
}

.footer-legal a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.15s ease;
}

.footer-legal a:hover {
  color: var(--text-primary);
}

/* --------------------------------------------------------------------------
   响应式：平板
   -------------------------------------------------------------------------- */

@media (max-width: 1100px) {
  :root {
    --gutter: 40px;
  }

  .hero-title {
    font-size: 56px;
  }

  .card-grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .point-grid {
    grid-template-columns: 1fr;
    max-width: 640px;
    gap: 24px;
  }

  .faq-inner {
    flex-direction: column;
    gap: 32px;
  }

  .faq-left {
    flex-basis: auto;
  }
}

/* --------------------------------------------------------------------------
   响应式：手机（依据 390 宽画板）
   -------------------------------------------------------------------------- */

@media (max-width: 767px) {
  :root {
    --gutter: 20px;
  }

  .nav-inner {
    height: 56px;
  }

  .hero {
    padding: 56px 0 48px;
  }

  .hero-inner {
    gap: 20px;
  }

  .hero-title {
    font-size: 36px;
    line-height: 1.25;
    gap: 8px;
  }

  .hero-title span,
  .hero-title .accent {
    display: block;
  }

  .hero-subtitle {
    font-size: 15px;
  }

  .hero-subtitle br {
    display: none;
  }

  .hero-note {
    font-size: 12px;
  }

  .features,
  .real,
  .privacy,
  .pricing,
  .steps,
  .faq {
    padding: 56px 0;
  }

  .section-stack,
  .section-stack-lg {
    gap: 32px;
  }

  .section-title,
  .privacy .section-title,
  .faq-left .section-title {
    font-size: 28px;
  }

  .section-subtitle {
    font-size: 14px;
  }

  .card-grid-4 {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .feature-card {
    padding: 20px;
    gap: 12px;
  }

  .privacy-card {
    padding: 18px;
    gap: 10px;
  }

  .point {
    gap: 12px;
  }

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

  .step {
    padding: 24px 20px;
    gap: 14px;
  }

  .step h3 {
    font-size: 18px;
  }

  .faq-item {
    padding: 16px 18px;
  }

  .footer {
    padding: 40px 0 24px;
  }

  .footer-bottom {
    margin-top: 32px;
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
}