:root {
  --blue: #1e6fd9;
  --blue-dark: #1557b0;
  --blue-soft: #e8f2fc;
  --ink: #1a2332;
  --muted: #5a6678;
  --line: #d9e2ec;
  --bg: #f5f8fc;
  --white: #ffffff;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(21, 87, 176, 0.08);
  --max: 1120px;
  --font: "Noto Sans SC", "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: var(--bg);
  line-height: 1.75;
  font-size: 16px;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--blue); text-decoration: none; }
a:hover { color: var(--blue-dark); text-decoration: underline; }
ul, ol { padding-left: 1.2em; }
h1, h2, h3, h4 { line-height: 1.35; color: var(--ink); font-weight: 700; }
h1 { font-size: clamp(1.7rem, 3vw, 2.35rem); margin-bottom: 0.7rem; }
h2 { font-size: clamp(1.35rem, 2.4vw, 1.85rem); margin: 0 0 0.8rem; }
h3 { font-size: 1.15rem; margin: 0 0 0.55rem; }
p { margin-bottom: 1rem; color: var(--muted); }
.container { width: min(100% - 2rem, var(--max)); margin-inline: auto; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.96);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 68px;
  gap: 1rem;
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--ink);
  text-decoration: none;
  font-weight: 700;
  font-size: 1.05rem;
}
.brand:hover { text-decoration: none; color: var(--blue); }
.brand img {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  object-fit: cover;
}
.nav {
  display: flex;
  align-items: center;
  gap: 0.35rem 1.1rem;
  flex-wrap: wrap;
}
.nav a {
  color: var(--ink);
  font-size: 0.95rem;
  font-weight: 500;
  text-decoration: none;
  padding: 0.35rem 0;
}
.nav a:hover,
.nav a.active { color: var(--blue); }
.menu-toggle {
  display: none;
  width: 42px;
  height: 42px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  background: var(--white);
  border-radius: 10px;
  padding: 0;
  cursor: pointer;
  color: var(--ink);
  flex-shrink: 0;
}
.menu-toggle-icon,
.menu-toggle-icon::before,
.menu-toggle-icon::after {
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition: transform .2s ease, opacity .2s ease;
}
.menu-toggle-icon {
  position: relative;
}
.menu-toggle-icon::before,
.menu-toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
}
.menu-toggle-icon::before { top: -6px; }
.menu-toggle-icon::after { top: 6px; }
.menu-toggle[aria-expanded="true"] .menu-toggle-icon {
  background: transparent;
}
.menu-toggle[aria-expanded="true"] .menu-toggle-icon::before {
  top: 0;
  transform: rotate(45deg);
}
.menu-toggle[aria-expanded="true"] .menu-toggle-icon::after {
  top: 0;
  transform: rotate(-45deg);
}

/* Hero */
.hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 12% 20%, rgba(30,111,217,0.18), transparent 42%),
    radial-gradient(circle at 88% 10%, rgba(56,189,248,0.16), transparent 36%),
    linear-gradient(180deg, #eff6ff 0%, #f5f8fc 70%);
  padding: 3.2rem 0 2.4rem;
  border-bottom: 1px solid var(--line);
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 2rem;
  align-items: center;
}
.hero-badge {
  display: inline-block;
  background: var(--blue-soft);
  color: var(--blue-dark);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  margin-bottom: 0.9rem;
}
.hero p.lead {
  font-size: 1.05rem;
  color: var(--muted);
  max-width: 38rem;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 1.4rem 0 1rem;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.85rem 1.35rem;
  border-radius: 12px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: transform .15s ease, background .15s ease, box-shadow .15s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary {
  background: var(--blue);
  color: #fff;
  box-shadow: 0 8px 20px rgba(30,111,217,0.28);
}
.btn-primary:hover { background: var(--blue-dark); color: #fff; }
.btn-secondary {
  background: #fff;
  color: var(--blue-dark);
  border: 1px solid #bdd4f5;
}
.btn-secondary:hover { background: var(--blue-soft); color: var(--blue-dark); }
.hero-visual {
  display: flex;
  justify-content: center;
}
.phone-frame {
  width: min(100%, 280px);
  background: #111827;
  border-radius: 28px;
  padding: 10px;
  box-shadow: var(--shadow), 0 20px 50px rgba(15, 40, 80, 0.18);
}
.phone-frame img {
  border-radius: 20px;
  width: 100%;
}
.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem 1.4rem;
  color: var(--muted);
  font-size: 0.92rem;
  margin-top: 0.5rem;
}

/* Sections */
.section { padding: 3rem 0; }
.section.alt { background: #fff; border-block: 1px solid var(--line); }
.section-head {
  max-width: 46rem;
  margin-bottom: 1.6rem;
}
.section-head p { margin-bottom: 0; }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.1rem;
}
.feature-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.2rem;
  box-shadow: var(--shadow);
}
.feature-card h3 { color: var(--blue-dark); }
.feature-card p { margin-bottom: 0; font-size: 0.96rem; }

.shot-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}
.shot-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.shot-item img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  background: #eef3f9;
}
.shot-item figcaption {
  padding: 0.75rem 0.85rem 0.95rem;
  font-size: 0.9rem;
  color: var(--muted);
}
.shot-item strong {
  display: block;
  color: var(--ink);
  margin-bottom: 0.25rem;
  font-size: 0.98rem;
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  align-items: center;
}
.split.reverse .split-text { order: 2; }
.split.reverse .split-media { order: 1; }
.split-media {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0.75rem;
  box-shadow: var(--shadow);
}
.split-media img {
  width: 100%;
  border-radius: 10px;
  max-height: 560px;
  object-fit: contain;
  background: #f0f5fb;
}
.split-text ul { margin-bottom: 1rem; color: var(--muted); }
.split-text li { margin-bottom: 0.4rem; }

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  counter-reset: step;
}
.step {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.15rem;
  position: relative;
}
.step::before {
  counter-increment: step;
  content: counter(step);
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--blue);
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 700;
  margin-bottom: 0.7rem;
}
.step p { margin: 0; font-size: 0.95rem; }

.faq details {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.95rem 1.1rem;
  margin-bottom: 0.7rem;
}
.faq summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--ink);
}
.faq details p {
  margin: 0.7rem 0 0;
  font-size: 0.96rem;
}

.prose {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.4rem 1.5rem;
  box-shadow: var(--shadow);
}
.prose h2 { margin-top: 1.6rem; }
.prose h2:first-child { margin-top: 0; }
.prose h3 { margin-top: 1.2rem; }
.prose a { font-weight: 500; }
.toc {
  background: var(--blue-soft);
  border: 1px solid #c9def7;
  border-radius: 12px;
  padding: 1rem 1.1rem;
  margin-bottom: 1.4rem;
}
.toc strong { display: block; margin-bottom: 0.45rem; color: var(--blue-dark); }
.toc a { display: inline-block; margin-right: 0.9rem; margin-bottom: 0.35rem; }

.page-hero {
  padding: 2.2rem 0 1.2rem;
  background: linear-gradient(180deg, #eef5ff, #f5f8fc);
  border-bottom: 1px solid var(--line);
}
.page-hero p { max-width: 46rem; margin-bottom: 0; }

.cta-band {
  background: linear-gradient(135deg, #1e6fd9, #0f4ea8);
  color: #fff;
  border-radius: 18px;
  padding: 1.8rem 1.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
  box-shadow: var(--shadow);
}
.cta-band h2, .cta-band p { color: #fff; margin: 0; }
.cta-band p { opacity: 0.92; margin-top: 0.4rem; }
.cta-band .btn-primary {
  background: #fff;
  color: var(--blue-dark);
  box-shadow: none;
}
.cta-band .btn-primary:hover { background: #e8f2fc; color: var(--blue-dark); }

/* Footer */
.site-footer {
  background: #122033;
  color: #c9d5e5;
  padding: 2.4rem 0 1.4rem;
  margin-top: 2rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}
.site-footer h3 {
  color: #fff;
  font-size: 1rem;
  margin-bottom: 0.7rem;
}
.site-footer a { color: #c9d5e5; }
.site-footer a:hover { color: #fff; }
.site-footer p { color: #9eb0c7; }
.footer-links { list-style: none; padding: 0; }
.footer-links li { margin-bottom: 0.4rem; }
.copyright {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 1rem;
  font-size: 0.88rem;
  color: #8ea0b8;
}

/* Error pages */
.error-wrap {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 3rem 1rem;
}
.error-wrap .code {
  font-size: clamp(3.5rem, 10vw, 6rem);
  font-weight: 800;
  color: var(--blue);
  line-height: 1;
  margin-bottom: 0.5rem;
}

/* Tables */
.table-wrap { overflow-x: auto; margin: 1rem 0; }
table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
}
th, td {
  border-bottom: 1px solid var(--line);
  padding: 0.75rem 0.9rem;
  text-align: left;
  font-size: 0.95rem;
}
th { background: var(--blue-soft); color: var(--blue-dark); }
td { color: var(--muted); }

@media (max-width: 960px) {
  .hero-grid,
  .split,
  .split.reverse,
  .feature-grid,
  .steps,
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .split.reverse .split-text,
  .split.reverse .split-media { order: initial; }
  .shot-grid { grid-template-columns: repeat(3, 1fr); }
  .hero { padding-top: 2rem; }
  .phone-frame { width: min(100%, 240px); }
}

@media (max-width: 720px) {
  .menu-toggle { display: inline-flex; }
  .nav {
    display: none;
    position: absolute;
    top: calc(100% - 1px);
    left: 0;
    right: 0;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.55rem 0.85rem 0.85rem;
    background: rgba(255,255,255,0.98);
    border: 1px solid var(--line);
    border-radius: 0 0 14px 14px;
    box-shadow: 0 14px 28px rgba(21, 87, 176, 0.12);
    z-index: 120;
  }
  .nav.open { display: flex; }
  .nav a {
    width: 100%;
    padding: 0.7rem 0.35rem;
    border-bottom: 1px solid var(--line);
  }
  .nav a:last-child { border-bottom: none; }
  .shot-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .btn { width: 100%; }
  .section { padding: 2.2rem 0; }
  .prose { padding: 1.1rem; }
}

@media (max-width: 420px) {
  .shot-grid { grid-template-columns: 1fr 1fr; gap: 0.7rem; }
}