:root {
  --blue: #2b9fff;
  --blue-dark: #0a6fd4;
  --blue-deep: #0b4f9c;
  --sky: #e8f5ff;
  --ink: #1a2433;
  --muted: #5a6b7d;
  --line: #d7e6f3;
  --card: #ffffff;
  --bg: #f4f9fd;
  --accent: #ff7a3d;
  --radius: 16px;
  --shadow: 0 12px 40px rgba(11, 79, 156, 0.08);
  --max: 1120px;
  --font: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  color: var(--ink);
  background:
    radial-gradient(circle at 10% -10%, #d9efff 0%, transparent 42%),
    radial-gradient(circle at 90% 0%, #fff1e8 0%, transparent 36%),
    linear-gradient(180deg, #f7fbff 0%, var(--bg) 48%, #eef6fc 100%);
  line-height: 1.75;
  min-height: 100vh;
}

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

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

a:hover {
  color: var(--blue);
}

.container {
  width: min(100% - 32px, var(--max));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(255, 255, 255, 0.88);
  border-bottom: 1px solid rgba(215, 230, 243, 0.9);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 72px;
  position: relative;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  font-weight: 700;
  font-size: 1.05rem;
}

.brand img {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  object-fit: cover;
  box-shadow: 0 6px 16px rgba(43, 159, 255, 0.25);
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  align-items: center;
}

.nav a {
  color: var(--muted);
  font-size: 0.95rem;
  font-weight: 600;
}

.nav a:hover,
.nav a.active {
  color: var(--blue-dark);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  border: none;
  background: linear-gradient(135deg, var(--blue) 0%, var(--blue-dark) 100%);
  color: #fff !important;
  font-weight: 700;
  box-shadow: 0 10px 24px rgba(43, 159, 255, 0.35);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 28px rgba(43, 159, 255, 0.42);
}

.btn-ghost {
  background: #fff;
  color: var(--blue-dark) !important;
  border: 1px solid var(--line);
  box-shadow: none;
}

.btn-accent {
  background: linear-gradient(135deg, #ff9460 0%, var(--accent) 100%);
  box-shadow: 0 10px 24px rgba(255, 122, 61, 0.28);
}

.hero {
  padding: 48px 0 28px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 36px;
  align-items: center;
}

.eyebrow {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  background: var(--sky);
  color: var(--blue-dark);
  font-size: 0.85rem;
  font-weight: 700;
  margin-bottom: 14px;
}

.hero h1 {
  font-size: clamp(1.8rem, 3.4vw, 2.7rem);
  line-height: 1.25;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.hero-lead {
  color: var(--muted);
  font-size: 1.05rem;
  margin-bottom: 24px;
  max-width: 36em;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 18px;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  color: var(--muted);
  font-size: 0.92rem;
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  width: 100%;
  border-radius: 24px;
  box-shadow: var(--shadow);
  border: 1px solid rgba(255, 255, 255, 0.7);
}

.hero-badge {
  position: absolute;
  left: 16px;
  bottom: 16px;
  background: rgba(255, 255, 255, 0.94);
  padding: 10px 14px;
  border-radius: 12px;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--blue-deep);
  box-shadow: var(--shadow);
}

.section {
  padding: 42px 0;
}

.section-head {
  margin-bottom: 24px;
}

.section-head h2 {
  font-size: clamp(1.45rem, 2.4vw, 2rem);
  margin-bottom: 10px;
}

.section-head p {
  color: var(--muted);
  max-width: 48em;
}

.panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px;
}

.prose h2,
.prose h3 {
  margin: 1.4em 0 0.65em;
  line-height: 1.35;
}

.prose h2:first-child,
.prose h3:first-child {
  margin-top: 0;
}

.prose p {
  margin-bottom: 1em;
  color: #243447;
}

.prose ul,
.prose ol {
  margin: 0 0 1.1em 1.2em;
  color: #243447;
}

.prose li {
  margin-bottom: 0.45em;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.feature-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform 0.2s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
}

.feature-card img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  background: #eef5fb;
}

.feature-card .body {
  padding: 16px 18px 20px;
}

.feature-card h3 {
  font-size: 1.05rem;
  margin-bottom: 8px;
}

.feature-card p {
  color: var(--muted);
  font-size: 0.94rem;
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  align-items: center;
  margin-bottom: 28px;
}

.split.reverse .copy {
  order: 2;
}

.split.reverse .media {
  order: 1;
}

.split .media img {
  width: 100%;
  border-radius: 18px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  max-height: 560px;
  object-fit: cover;
  object-position: top;
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.step {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow);
}

.step .num {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--sky);
  color: var(--blue-dark);
  font-weight: 800;
  margin-bottom: 12px;
}

.step h3 {
  font-size: 1rem;
  margin-bottom: 8px;
}

.step p {
  color: var(--muted);
  font-size: 0.92rem;
}

.gallery {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}

.gallery figure {
  margin: 0;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.gallery img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
}

.gallery figcaption {
  padding: 10px 12px 14px;
  font-size: 0.86rem;
  color: var(--muted);
}

.faq details {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px 18px;
  margin-bottom: 10px;
}

.faq summary {
  cursor: pointer;
  font-weight: 700;
  color: var(--ink);
}

.faq details p {
  margin-top: 10px;
  color: var(--muted);
}

.cta-band {
  margin: 20px 0 10px;
  padding: 36px;
  border-radius: 24px;
  background: linear-gradient(135deg, rgba(43, 159, 255, 0.98), rgba(11, 79, 156, 0.96));
  color: #fff;
  text-align: center;
  box-shadow: var(--shadow);
}

.cta-band h2 {
  margin-bottom: 10px;
}

.cta-band p {
  opacity: 0.92;
  margin-bottom: 18px;
}

.links-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 16px;
  margin-top: 12px;
}

.chip {
  display: inline-block;
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--sky);
  color: var(--blue-deep);
  font-size: 0.88rem;
  font-weight: 600;
}

.site-footer {
  margin-top: 48px;
  padding: 36px 0 28px;
  background: #0d2b4a;
  color: #d7e6f3;
}

.site-footer a {
  color: #b8d8f5;
}

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

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 24px;
  margin-bottom: 24px;
}

.footer-grid h3 {
  color: #fff;
  margin-bottom: 12px;
  font-size: 1rem;
}

.footer-grid ul {
  list-style: none;
}

.footer-grid li {
  margin-bottom: 8px;
}

.copyright {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: 16px;
  font-size: 0.88rem;
  color: #9db6cc;
}

.error-page {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 60px 0;
}

.error-page .code {
  font-size: clamp(3rem, 10vw, 6rem);
  font-weight: 800;
  color: var(--blue);
  line-height: 1;
  margin-bottom: 10px;
}

.toc {
  background: var(--sky);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px 20px;
  margin-bottom: 24px;
}

.toc h2 {
  font-size: 1.05rem;
  margin-bottom: 10px;
}

.toc ol {
  margin-left: 1.1em;
}

.toc li {
  margin-bottom: 6px;
}

.menu-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 10px;
  color: var(--blue-dark);
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

.menu-toggle .icon {
  display: block;
  width: 20px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  position: relative;
  box-shadow: 0 -6px 0 currentColor, 0 6px 0 currentColor;
}

@media (max-width: 980px) {
  .hero-grid,
  .split,
  .split.reverse,
  .feature-grid,
  .steps,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .split.reverse .copy,
  .split.reverse .media {
    order: initial;
  }

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

  .feature-card img,
  .gallery img,
  .split .media img {
    max-height: 420px;
  }
}

@media (max-width: 760px) {
  .menu-toggle {
    display: inline-flex;
  }

  .nav {
    display: none;
  }

  .nav.open {
    display: flex;
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    left: auto;
    width: min(280px, calc(100vw - 32px));
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 12px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 14px;
    box-shadow: var(--shadow);
    z-index: 120;
  }

  .nav.open a {
    padding: 10px 12px;
    border-radius: 10px;
  }

  .nav.open a:hover,
  .nav.open a.active {
    background: var(--sky);
  }

  .nav.open .btn {
    width: 100%;
    margin-top: 4px;
  }

  .header-inner {
    flex-wrap: nowrap;
    min-height: 64px;
  }

  .hero {
    padding-top: 28px;
  }

  .panel,
  .cta-band {
    padding: 20px;
  }

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

@media (max-width: 520px) {
  .feature-grid,
  .steps,
  .gallery {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }
}