:root {
  --blue: #1a6cff;
  --blue-dark: #0d4fd6;
  --blue-soft: #e8f1ff;
  --ink: #1a1f2e;
  --muted: #5a6478;
  --line: #dce3ef;
  --bg: #f5f8fc;
  --white: #ffffff;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(26, 108, 255, 0.08);
  --max: 1100px;
  --font: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  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 {
  text-decoration: underline;
}

.container {
  width: min(100% - 32px, var(--max));
  margin: 0 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 {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 68px;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 700;
  font-size: 1.05rem;
  text-decoration: none;
}

.brand img {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  object-fit: cover;
}

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

.nav a {
  color: var(--muted);
  font-size: 0.95rem;
  text-decoration: none;
}

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

.menu-toggle {
  display: none;
  border: 1px solid var(--line);
  background: var(--white);
  border-radius: 8px;
  padding: 8px 12px;
  cursor: pointer;
  color: var(--ink);
  font-size: 0.9rem;
}

/* Hero */
.hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 15% 20%, rgba(26, 108, 255, 0.18), transparent 40%),
    radial-gradient(circle at 85% 10%, rgba(64, 196, 255, 0.16), transparent 35%),
    linear-gradient(180deg, #ffffff 0%, #eef5ff 100%);
  padding: 56px 0 40px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 36px;
  align-items: center;
}

.hero-badge {
  display: inline-block;
  background: var(--blue-soft);
  color: var(--blue-dark);
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 0.85rem;
  margin-bottom: 14px;
}

.hero h1 {
  margin: 0 0 14px;
  font-size: clamp(1.7rem, 3.2vw, 2.45rem);
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.hero-lead {
  color: var(--muted);
  font-size: 1.05rem;
  margin: 0 0 24px;
  max-width: 36em;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 18px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 10px;
  border: none;
  font-weight: 600;
  font-size: 0.98rem;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.btn:hover {
  text-decoration: none;
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--blue);
  color: #fff;
  box-shadow: 0 8px 20px rgba(26, 108, 255, 0.28);
}

.btn-primary:hover {
  background: var(--blue-dark);
  color: #fff;
}

.btn-secondary {
  background: #fff;
  color: var(--blue-dark);
  border: 1px solid #c7d8f8;
}

.btn-secondary:hover {
  background: var(--blue-soft);
  color: var(--blue-dark);
}

.hero-note {
  font-size: 0.9rem;
  color: var(--muted);
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  width: min(100%, 340px);
  margin: 0 auto;
  border-radius: 22px;
  box-shadow: 0 18px 50px rgba(13, 79, 214, 0.22);
  border: 4px solid #fff;
}

/* Sections */
.section {
  padding: 56px 0;
}

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

.section-head {
  margin-bottom: 28px;
  max-width: 48em;
}

.section-head h2 {
  margin: 0 0 10px;
  font-size: clamp(1.35rem, 2.4vw, 1.85rem);
  line-height: 1.3;
}

.section-head p {
  margin: 0;
  color: var(--muted);
}

.prose p {
  margin: 0 0 1em;
  color: #2c3448;
}

.prose h3 {
  margin: 1.6em 0 0.6em;
  font-size: 1.2rem;
}

.prose ul,
.prose ol {
  margin: 0 0 1.1em;
  padding-left: 1.3em;
  color: #2c3448;
}

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

/* Feature blocks */
.feature-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  align-items: center;
  margin-bottom: 42px;
}

.feature-block:last-child {
  margin-bottom: 0;
}

.feature-block.reverse .feature-copy {
  order: 2;
}

.feature-block.reverse .feature-media {
  order: 1;
}

.feature-media {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.feature-media.single {
  grid-template-columns: 1fr;
  justify-items: center;
}

.feature-media img {
  border-radius: 16px;
  box-shadow: var(--shadow);
  border: 1px solid var(--line);
  background: #fff;
}

.feature-media.single img {
  width: min(100%, 320px);
}

.feature-copy h3 {
  margin: 0 0 10px;
  font-size: 1.25rem;
}

.feature-copy p {
  margin: 0 0 0.85em;
  color: #2c3448;
}

.shot-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.shot-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

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

.shot-card figcaption {
  padding: 12px 14px 14px;
  font-size: 0.92rem;
  color: var(--muted);
}

.shot-card strong {
  display: block;
  color: var(--ink);
  margin-bottom: 4px;
}

/* Steps */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  counter-reset: step;
}

.step {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 18px;
  box-shadow: var(--shadow);
}

.step::before {
  counter-increment: step;
  content: "0" counter(step);
  display: inline-block;
  font-weight: 700;
  color: var(--blue);
  margin-bottom: 8px;
}

.step h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
}

.step p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

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

.faq summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--ink);
}

.faq details p {
  margin: 10px 0 0;
  color: var(--muted);
}

/* Legal / content pages */
.page-hero {
  background: linear-gradient(180deg, #ffffff, #eef5ff);
  padding: 42px 0 28px;
  border-bottom: 1px solid var(--line);
}

.page-hero h1 {
  margin: 0 0 10px;
  font-size: clamp(1.5rem, 2.8vw, 2rem);
}

.page-hero p {
  margin: 0;
  color: var(--muted);
}

.content-wrap {
  padding: 36px 0 60px;
}

.content-panel {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 28px 26px;
  box-shadow: var(--shadow);
}

.breadcrumb {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 14px;
}

.breadcrumb a {
  color: var(--muted);
}

.related-links {
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.related-links h3 {
  margin: 0 0 10px;
  font-size: 1.05rem;
}

.related-links ul {
  margin: 0;
  padding-left: 1.2em;
}

.related-links li {
  margin-bottom: 6px;
}

/* Error pages */
.error-page {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 60px 16px;
}

.error-page h1 {
  font-size: 3.5rem;
  margin: 0 0 8px;
  color: var(--blue);
}

.error-page p {
  color: var(--muted);
  margin: 0 0 22px;
}

/* Footer */
.site-footer {
  background: #0f1b33;
  color: #c9d4ea;
  padding: 40px 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 24px;
}

.footer-brand {
  display: flex;
  gap: 12px;
  align-items: flex-start;
}

.footer-brand img {
  width: 44px;
  height: 44px;
  border-radius: 10px;
}

.footer-brand strong {
  display: block;
  color: #fff;
  margin-bottom: 6px;
}

.footer-brand p,
.site-footer p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.7;
}

.site-footer h4 {
  margin: 0 0 12px;
  color: #fff;
  font-size: 0.98rem;
}

.site-footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

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

.site-footer a {
  color: #c9d4ea;
  text-decoration: none;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 16px;
  font-size: 0.88rem;
  color: #8fa0bf;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  justify-content: space-between;
}

.toc {
  background: var(--blue-soft);
  border-radius: 12px;
  padding: 16px 18px;
  margin-bottom: 24px;
}

.toc strong {
  display: block;
  margin-bottom: 8px;
}

.toc a {
  display: inline-block;
  margin: 0 12px 6px 0;
  color: var(--blue-dark);
  font-size: 0.95rem;
}

.highlight-box {
  background: linear-gradient(135deg, #f0f6ff, #ffffff);
  border: 1px solid #cfe0ff;
  border-radius: 14px;
  padding: 18px 20px;
  margin: 20px 0;
}

.inline-shots {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin: 20px 0 8px;
}

.inline-shots img {
  border-radius: 12px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

/* Mobile */
@media (max-width: 900px) {
  .hero-grid,
  .feature-block,
  .feature-block.reverse,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .feature-block.reverse .feature-copy,
  .feature-block.reverse .feature-media {
    order: initial;
  }

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

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

  .inline-shots {
    grid-template-columns: 1fr 1fr;
  }

  .menu-toggle {
    display: inline-flex;
  }

  .nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: flex-start;
    padding: 8px 0 16px;
  }

  .nav.open {
    display: flex;
  }

  .header-inner {
    flex-wrap: wrap;
  }

  .hero {
    padding: 36px 0 28px;
  }

  .hero-visual {
    order: -1;
  }

  .hero-visual img {
    width: min(100%, 260px);
  }

  .section {
    padding: 40px 0;
  }

  .content-panel {
    padding: 20px 16px;
  }
}

@media (max-width: 560px) {
  .steps,
  .shot-grid {
    grid-template-columns: 1fr;
  }

  .feature-media {
    grid-template-columns: 1fr;
  }

  .feature-media img {
    width: min(100%, 280px);
    margin: 0 auto;
  }

  .cta-row {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }
}