:root {
  --bg: #ffffff;
  --bg-alt: #f8fafc;
  --text: #111827;
  --muted: #6b7280;
  --line: #e5e7eb;
  --primary: #0052ff;
  --primary-hover: #0041cc;
  --yellow: #f0b90b;
  --radius: 16px;
  --max: 1120px;
  --header-h: 72px;
}

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

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 16px); }

body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

body.menu-open { overflow: hidden; }

a { color: inherit; text-decoration: none; }
button, input { font-family: inherit; }
img { max-width: 100%; height: auto; display: block; }

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 3px solid rgba(0, 82, 255, 0.35);
  outline-offset: 3px;
  border-radius: 4px;
}

.container { width: min(var(--max), calc(100% - 40px)); margin: 0 auto; }
.container.narrow { max-width: 720px; }
.narrow-block { max-width: 720px; margin-bottom: 32px; }

.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 32px;
  height: var(--header-h);
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  font-size: 14px;
  font-weight: 700;
}

.logo img { width: 36px; height: 36px; }

.nav { display: flex; gap: 28px; margin-left: auto; }
.nav a { font-size: 15px; font-weight: 500; color: var(--muted); }
.nav a:hover { color: var(--text); }

.header-actions { display: flex; align-items: center; gap: 8px; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 40px;
  padding: 0 20px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  border: 0;
  cursor: pointer;
}

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-hover); }
.btn-outline {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--line);
}
.btn-outline:hover { border-color: var(--text); background: var(--bg-alt); }
.btn-lg { height: 52px; padding: 0 32px; font-size: 16px; }

.hamburger {
  display: none;
  width: 40px;
  height: 40px;
  border: 0;
  background: transparent;
  cursor: pointer;
  border-radius: 8px;
}

.mobile-nav {
  display: none;
  position: fixed;
  inset: var(--header-h) 0 0;
  background: var(--bg);
  z-index: 90;
  padding: 24px;
}

.mobile-nav.open { display: block; }
.mobile-nav a {
  display: block;
  padding: 16px 0;
  font-size: 18px;
  font-weight: 500;
  border-bottom: 1px solid var(--line);
}

.breadcrumb {
  padding: 16px 0 0;
  font-size: 14px;
  color: var(--muted);
}

.breadcrumb a:hover { color: var(--text); }
.breadcrumb .sep { margin: 0 8px; color: var(--line); }
.breadcrumb [aria-current="page"] { color: var(--text); }

.hero { padding: 48px 0 64px; }
.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.kicker {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  letter-spacing: 0.04em;
  margin-bottom: 16px;
}

.hero h1 {
  font-size: clamp(2rem, 4.5vw, 2.75rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.03em;
  margin-bottom: 20px;
}

.lead { font-size: 18px; color: var(--muted); margin-bottom: 28px; max-width: 520px; }

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 24px;
}

.disclaimer-box {
  font-size: 13px;
  color: var(--muted);
  background: var(--bg-alt);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px 16px;
  max-width: 520px;
  line-height: 1.5;
}

.section { padding: 72px 0; }
.section-alt { background: var(--bg-alt); }

.section-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.section-sub { color: var(--muted); margin-bottom: 40px; }

.flow-steps {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px 0;
  margin-bottom: 32px;
}

.flow-steps li {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  position: relative;
  min-width: 120px;
  padding: 0 16px 8px;
}

.flow-steps li:not(:last-child)::after {
  content: "↓";
  position: absolute;
  right: -6px;
  top: 18px;
  color: var(--muted);
  font-size: 14px;
  transform: rotate(-90deg);
}

.flow-num {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 16px;
  margin-bottom: 10px;
}

.flow-label { font-size: 14px; font-weight: 600; color: var(--text); }

.overview-note {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
  color: var(--muted);
}

.toc-section { padding-top: 48px; padding-bottom: 48px; }

.toc {
  list-style: none;
  counter-reset: toc;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.toc li {
  counter-increment: toc;
  border-bottom: 1px solid var(--line);
}

.toc a {
  display: flex;
  gap: 12px;
  padding: 14px 0;
  font-weight: 500;
  color: var(--text);
}

.toc a::before {
  content: counter(toc) ".";
  color: var(--muted);
  font-variant-numeric: tabular-nums;
  min-width: 1.5em;
}

.toc a:hover { color: var(--primary); }

.prose p { color: var(--muted); margin-bottom: 16px; }
.prose h2:not(.section-title) {
  font-size: 1.4rem;
  font-weight: 750;
  margin: 36px 0 14px;
  color: var(--text);
}
.prose h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin: 28px 0 12px;
  color: var(--text);
}
.prose ul {
  margin: 0 0 20px 1.25em;
  color: var(--muted);
}
.prose ul li { margin-bottom: 8px; }
.prose ul strong { color: var(--text); }

.step-list {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  border-left: 2px solid var(--line);
  margin-left: 12px;
}

.step-list li {
  position: relative;
  padding: 0 0 16px 24px;
  color: var(--muted);
  font-weight: 500;
}

.step-list li:last-child { padding-bottom: 0; }

.step-list li::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 8px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--primary);
}

.step-list li:not(:last-child)::after {
  content: "↓";
  display: block;
  margin-top: 8px;
  color: var(--line);
  font-size: 12px;
  line-height: 1;
}

.content-img {
  margin: 24px 0;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  max-width: 480px;
}

.content-figure {
  margin: 24px 0;
  max-width: 800px;
}

.content-figure .content-img,
.content-figure .pay-wall { margin-bottom: 10px; }

.content-figure figcaption {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.5;
}

.pay-figure { margin: 0 auto 40px; }

.timeline { list-style: none; max-width: 640px; margin: 24px 0 32px; }

.timeline li {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 24px;
  padding-bottom: 40px;
  position: relative;
}

.timeline li:not(:last-child)::before {
  content: "";
  position: absolute;
  left: 27px;
  top: 56px;
  bottom: 0;
  width: 2px;
  background: var(--line);
}

.tl-marker {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 14px;
  flex-shrink: 0;
}

.tl-body h3 { font-size: 20px; margin: 0 0 8px; color: var(--text); }
.tl-body p { color: var(--muted); margin: 0; }

.inline-cta {
  margin-top: 32px;
  padding: 24px;
  background: var(--bg-alt);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.inline-cta.center {
  text-align: center;
  background: var(--bg);
  margin-top: 40px;
}

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

.inline-cta .btn { margin-bottom: 12px; }
.inline-cta.center .btn { margin-bottom: 0; }

.inline-cta-note {
  font-size: 14px;
  color: var(--muted);
  margin: 0;
}

.inline-cta-note a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.pay-wall { margin: 0 auto; border-radius: var(--radius); }

.pay-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.pay-cards article {
  padding: 28px;
  background: var(--bg);
  border-radius: var(--radius);
  border: 1px solid var(--line);
  display: flex;
  flex-direction: column;
}

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

.pay-cards h3 { font-size: 18px; margin-bottom: 8px; }
.pay-cards > article > p { font-size: 15px; color: var(--muted); margin-bottom: 16px; }

.card-points {
  list-style: none;
  margin: 0 0 16px;
  padding: 0;
  flex: 1;
}

.card-points li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 8px;
}

.card-points li::before {
  content: "·";
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

.text-link {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
}

.text-link:hover { text-decoration: underline; text-underline-offset: 2px; }

.source-link {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.source-note {
  font-size: 14px;
  padding: 12px 16px;
  border-left: 3px solid var(--line);
}

.verification-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin: 24px 0;
}

.verification-grid > div {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0 24px 20px;
}

.update-log time {
  color: var(--text);
  font-weight: 600;
}

.table-wrap {
  overflow-x: auto;
  margin: 24px 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.fee-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  min-width: 480px;
}

.fee-table th,
.fee-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--line);
}

.fee-table th {
  background: var(--bg-alt);
  font-weight: 600;
  color: var(--text);
}

.fee-table td { color: var(--muted); }
.fee-table tr:last-child td { border-bottom: 0; }

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

.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0 20px;
  background: var(--bg);
}

.faq-item summary {
  padding: 20px 0;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
}

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

.faq-item p {
  padding-bottom: 20px;
  color: var(--muted);
  font-size: 15px;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.related-card {
  display: block;
  padding: 24px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.2s, box-shadow 0.2s;
}

.related-card:hover {
  border-color: var(--primary);
  box-shadow: 0 4px 16px rgba(0, 82, 255, 0.08);
}

.related-card h3 {
  font-size: 17px;
  margin-bottom: 6px;
}

.related-card p {
  font-size: 14px;
  color: var(--muted);
  margin: 0;
}

.cta-band {
  background: linear-gradient(135deg, #0052ff, #003db3);
  color: #fff;
  padding: 80px 0;
  text-align: center;
}

.cta-inner h2 { font-size: 2rem; margin-bottom: 12px; }
.cta-inner p { opacity: 0.9; margin-bottom: 28px; }
.cta-band .btn-primary { background: #fff; color: var(--primary); }
.cta-band .btn-primary:hover { background: #f0f4ff; }

.footer {
  padding: 32px 0;
  border-top: 1px solid var(--line);
}

.footer-bar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
}

.footer-risk,
.footer-updated {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
}

.footer-risk { max-width: 720px; }
.footer-updated {
  flex-shrink: 0;
  white-space: nowrap;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 24px;
}

.footer nav { display: flex; gap: 24px; margin-left: auto; }
.footer nav a { font-size: 14px; color: var(--muted); }

.meta-bar {
  width: 100%;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  font-size: 13px;
  color: var(--muted);
  margin-top: 8px;
}

.disclaimer {
  width: 100%;
  font-size: 13px;
  color: var(--muted);
  margin-top: 8px;
  line-height: 1.6;
}

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-visual { order: -1; max-width: 480px; margin: 0 auto; }
  .pay-cards { grid-template-columns: 1fr; }
  .related-grid { grid-template-columns: 1fr 1fr; }
  .flow-steps {
    flex-direction: column;
    align-items: stretch;
    max-width: 280px;
    margin-left: auto;
    margin-right: auto;
  }
  .flow-steps li {
    flex-direction: row;
    gap: 16px;
    text-align: left;
    min-width: 0;
    padding: 0 0 24px;
  }
  .flow-steps li:not(:last-child)::after {
    content: "↓";
    position: absolute;
    left: 18px;
    top: auto;
    bottom: 4px;
    right: auto;
    transform: none;
  }
  .flow-num { margin-bottom: 0; flex-shrink: 0; }
}

@media (max-width: 768px) {
  .nav { display: none; }
  .hamburger { display: grid; place-items: center; }
  .footer nav { margin-left: 0; }
  .related-grid { grid-template-columns: 1fr; }
  .hero-cta { flex-direction: column; }
  .hero-cta .btn { width: 100%; }
  .verification-grid { grid-template-columns: 1fr; }
  .footer-bar { flex-direction: column; }
  .footer-updated { white-space: normal; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}