:root {
  --blue: #2f7bd8;
  --blue-dark: #0e2a43;
  --orange: #ff7a1a;
  --orange-dark: #ef6710;
  --line: #cce3f9;
  --text: #12263a;
  --muted: #63758a;
  --white: #fff;
  --orange-shadow: 0 12px 22px rgba(255, 122, 26, .28);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--text);
  font-family: "Noto Sans JP", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.85;
  background: #f8fafc;
}
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
.page-container { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }

.site-header {
  position: sticky; z-index: 20; top: 0;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(204, 227, 249, .7);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  min-height: 86px; gap: 22px;
}
.brand { display: grid; gap: 2px; flex: 0 0 auto; }
.brand-kicker {
  display: block; margin: 0; color: var(--blue-dark);
  font-size: 12px; font-weight: 900; line-height: 1.2;
}
.brand-main { display: block; color: #18569f; line-height: 1; }
.brand-name { display: block; margin: 0; font-size: 26px; font-weight: 900; line-height: 1; }
.nav {
  display: flex; align-items: center; justify-content: center; gap: 24px;
  color: #182d45; font-size: 14px; font-weight: 900; white-space: nowrap;
}
.nav a.is-current { color: var(--blue); }
.menu-toggle {
  display: none; width: 46px; height: 46px; padding: 0;
  border: 1px solid rgba(47, 123, 216, .28); border-radius: 10px;
  background: #fff; color: #1c4f88;
  flex-direction: column; align-items: center; justify-content: center; cursor: pointer;
}
.menu-toggle-line {
  display: block; width: 22px; height: 2px; background: currentColor; border-radius: 999px;
  transition: transform .25s ease, opacity .25s ease;
}
.menu-toggle-line + .menu-toggle-line { margin-top: 5px; }
.site-header.is-open .menu-toggle-line:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.site-header.is-open .menu-toggle-line:nth-child(2) { opacity: 0; }
.site-header.is-open .menu-toggle-line:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
.menu-overlay {
  display: none;
  position: fixed; inset: 0; background: rgba(10, 24, 42, .34);
  opacity: 0; pointer-events: none; transition: opacity .2s ease; z-index: 15;
}
.button {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 54px; padding: 0 24px; border: 0; border-radius: 8px;
  color: var(--white);
  background: linear-gradient(180deg, #ff8c2a, var(--orange));
  box-shadow: var(--orange-shadow);
  font: inherit; font-size: 15px; font-weight: 900; line-height: 1;
  white-space: nowrap; flex-shrink: 0; cursor: pointer;
}
.button.small { min-height: 48px; padding-inline: 20px; font-size: 13px; }
.button:hover { background: linear-gradient(180deg, #ff9438, var(--orange-dark)); transform: translateY(-1px); }

.footer {
  padding: 0; color: #d7e7f9;
  background: linear-gradient(120deg, #0d2b4c 0%, #123a62 60%, #185082 100%);
  font-size: 13px;
}
.footer-inner { padding: 34px 0 20px; }
.footer-top {
  display: grid; grid-template-columns: 1.25fr .85fr auto; gap: 24px; align-items: start;
  padding-bottom: 20px; border-bottom: 1px solid rgba(173, 210, 245, .25);
}
.footer-brand-logo { width: auto; height: 124px; max-width: 580px; object-fit: contain; object-position: left center; }
.footer-brand-text { margin: 10px 0 0; color: #c8ddf2; font-size: 13px; font-weight: 500; line-height: 1.8; }
.footer-links { display: grid; gap: 10px; margin: 0; padding: 0; list-style: none; }
.footer-links a { color: #d7e7f9; font-weight: 700; text-decoration: none; transition: color .2s ease; }
.footer-links a:hover { color: #fff; }
.footer-cta { display: inline-flex; min-height: 46px; font-size: 14px; }
.footer-bottom {
  display: flex; justify-content: space-between; gap: 12px; padding-top: 14px;
  color: #b9d3eb; font-size: 12px; font-weight: 500;
}

.page-hero {
  padding: 36px 0 28px;
  background: linear-gradient(180deg, #fff 0%, #eaf6ff 100%);
}
.breadcrumb {
  margin: 0 0 18px; color: var(--muted); font-size: 13px; font-weight: 700;
}
.breadcrumb ol {
  display: flex; flex-wrap: wrap; gap: 8px; align-items: center;
  margin: 0; padding: 0; list-style: none;
}
.breadcrumb li { display: flex; align-items: center; gap: 8px; }
.breadcrumb li:not(:last-child)::after {
  content: "/"; color: var(--muted); font-weight: 700;
}
.breadcrumb a { color: #18569f; }
.breadcrumb a:hover { text-decoration: underline; }
.toc {
  margin: 8px 0 32px;
  padding: 20px 22px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
}
.toc-title {
  margin: 0 0 10px; color: #123a62; font-size: 14px; font-weight: 900;
}
.toc ol { margin: 0; padding-left: 1.3em; }
.toc li { margin: 0 0 6px; font-size: 14px; font-weight: 700; }
.toc a { color: #18569f; text-decoration: none; }
.toc a:hover { text-decoration: underline; }
.page-kicker {
  margin: 0 0 8px; color: var(--blue); font-size: 12px; font-weight: 900; letter-spacing: .2em;
}
.page-title {
  margin: 0; color: #0b1f33; font-size: clamp(28px, 4vw, 42px);
  font-weight: 900; line-height: 1.4;
}
.page-lead {
  margin: 16px 0 0; max-width: 720px; color: #334155; font-size: 16px; font-weight: 500;
}

.blog-index { padding: 36px 0 80px; }
.blog-card {
  display: grid; grid-template-columns: minmax(240px, 360px) 1fr;
  gap: 28px; align-items: center;
  padding: 18px; border: 1px solid var(--line); border-radius: 16px;
  background: #fff; box-shadow: 0 12px 28px rgba(47, 123, 216, .1);
  transition: transform .2s ease, box-shadow .2s ease;
}
.blog-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 36px rgba(47, 123, 216, .16);
}
.blog-card-thumb {
  overflow: hidden; border-radius: 12px; background: #eaf6ff;
}
.blog-card-thumb img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.blog-card-date { margin: 0 0 8px; color: var(--muted); font-size: 13px; font-weight: 700; }
.blog-card-title { margin: 0 0 10px; color: #123a62; font-size: 22px; font-weight: 900; line-height: 1.5; }
.blog-card-excerpt { margin: 0; color: #4a6078; font-size: 15px; font-weight: 500; line-height: 1.8; }

.article-hero { padding: 28px 0 0; background: linear-gradient(180deg, #fff 0%, #f7fbff 100%); }
.article-meta {
  display: flex; flex-wrap: wrap; gap: 12px; align-items: center;
  margin: 0 0 14px; color: var(--muted); font-size: 13px; font-weight: 700;
}
.article-title {
  margin: 0 0 22px; color: #0b1f33;
  font-size: clamp(26px, 3.6vw, 40px); font-weight: 900; line-height: 1.45;
}
.article-hero-image {
  overflow: hidden; border-radius: 16px;
  box-shadow: 0 18px 40px rgba(14, 42, 67, .16);
}
.article-hero-image img { width: 100%; }

.article-body {
  --body-indent: 36px;
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
  padding: 48px 0 80px;
  padding-left: var(--body-indent);
}
.article-body h2 {
  width: calc(100% + var(--body-indent));
  margin: 48px 0 18px calc(var(--body-indent) * -1);
  padding-bottom: 10px;
  border-bottom: 3px solid #d7ebfb;
  color: #123a62; font-size: 24px; font-weight: 900; line-height: 1.5;
  scroll-margin-top: 96px;
}
.article-body p { margin: 0 0 18px; font-size: 17px; font-weight: 500; color: #1b2d40; }
.article-body .lead-text { font-size: 18px; }
.article-body ul, .article-body ol {
  margin: 0 0 22px; padding-left: 1.3em; font-size: 17px; font-weight: 500;
}
.article-body li { margin: 0 0 10px; }
.article-body a {
  color: #18569f; font-weight: 700; text-decoration: underline;
  text-underline-offset: 3px;
}
.article-body .toc a { text-decoration: none; }
.article-body .toc ol { margin: 0 0 0 0; padding-left: 1.3em; }
.article-body .note {
  margin: 8px 0 22px; padding: 16px 18px;
  border-left: 4px solid var(--blue);
  border-radius: 0 10px 10px 0;
  background: #eef7ff;
  color: #27425c; font-size: 15px;
}
.article-figure {
  width: 100%;
  margin: 32px 0 36px;
}
.article-figure img {
  width: 100%; border-radius: 14px;
  border: 1px solid var(--line);
  box-shadow: 0 12px 28px rgba(47, 123, 216, .12);
}
.article-figure figcaption {
  margin-top: 10px; color: var(--muted); font-size: 13px; font-weight: 700; text-align: center;
}
.article-figure.poster {
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}
.steps {
  display: grid; gap: 12px; margin: 8px 0 24px;
}
.step-item {
  display: grid; grid-template-columns: 42px 1fr; gap: 12px; align-items: start;
  padding: 14px 16px; border: 1px solid var(--line); border-radius: 12px; background: #fff;
}
.step-num {
  width: 42px; height: 42px; border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  color: #fff; background: var(--blue); font-size: 15px; font-weight: 900;
}
.step-item h3 { margin: 0 0 4px; color: #123a62; font-size: 16px; font-weight: 900; }
.step-item p { margin: 0; font-size: 15px; color: #4a6078; }
.compare-table {
  width: 100%; margin: 8px 0 22px; border-collapse: collapse;
  overflow: hidden; border-radius: 12px; background: #fff;
}
.compare-table th, .compare-table td {
  padding: 12px 14px; border: 1px solid var(--line); text-align: left; font-size: 15px;
}
.compare-table th { background: #eaf6ff; color: #123a62; font-weight: 900; }
.compare-table td { font-weight: 500; }
.compare-table .pick { background: #fff7ed; font-weight: 800; color: #c05612; }
.cta-box {
  margin: 28px 0;
  padding: 28px 24px;
  border-radius: 16px;
  background: linear-gradient(180deg, #123a62 0%, #0f2f53 100%);
  color: #fff;
  text-align: center;
}
.cta-box h3 { margin: 0 0 8px; font-size: 22px; font-weight: 900; }
.cta-box p { margin: 0 0 18px; color: #d7eaff; font-size: 15px; }
.cta-box a { text-decoration: none; }
.cta-box.affiliate {
  background: linear-gradient(180deg, #06c755 0%, #05a848 100%);
}
.cta-box.affiliate p { color: #e9ffe9; }
.cta-box .button { min-width: min(100%, 280px); }
.cta-buttons {
  display: flex; flex-wrap: wrap; gap: 12px; justify-content: center;
}
.cta-box .button.ghost {
  color: #fff;
  background: transparent;
  box-shadow: none;
  border: 2px solid rgba(255, 255, 255, .7);
}
.cta-box .button.ghost:hover {
  background: rgba(255, 255, 255, .12);
  transform: translateY(-1px);
}
.cta-box.affiliate .button {
  color: #056b2d;
  background: #fff;
  box-shadow: 0 10px 20px rgba(0, 0, 0, .12);
}
.cta-box.affiliate .button:hover {
  background: #f3fff6;
  transform: translateY(-1px);
}
.disclaimer {
  margin: 8px 0 0; color: var(--muted); font-size: 13px; text-align: center;
}
.back-link {
  display: inline-flex; margin-top: 12px; color: #18569f; font-weight: 800;
}
.back-link:hover { text-decoration: underline; }

@media (max-width: 980px) {
  body.menu-open { overflow: hidden; }
  .header-inner { min-height: auto; padding: 16px 0; flex-wrap: wrap; }
  .menu-toggle { display: inline-flex; margin-left: auto; }
  .menu-overlay { display: block; }
  .site-header.is-open + .menu-overlay { opacity: 1; pointer-events: auto; }
  .nav {
    display: none; order: 3; width: 100%; flex-direction: column; align-items: flex-start; gap: 12px;
    padding: 14px 0 4px; border-top: 1px solid rgba(204, 227, 249, .7); white-space: normal;
  }
  .site-header.is-open .nav { display: flex; }
  .site-header .button.small { display: none; }
  .footer-top { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .blog-card { grid-template-columns: 1fr; }
}
@media (max-width: 620px) {
  .page-container, .article-body { width: min(100% - 28px, 1120px); }
  .article-body { --body-indent: 20px; }
  .brand-name { font-size: 22px; }
  .footer-cta { width: 100%; }
  .article-body p, .article-body li { font-size: 16px; }
  .cta-box .button { width: 100%; }
}