/* 共通の色・幅。全体の印象を変える場合はここから編集。 */
:root {
  --ink: #172b40;
  --muted: #526273;
  --accent: #185adb;
  --line: #d7e0e8;
  --pale: #f3f6f9;
  --width: 1120px;
  --radius: 12px;
}
* { box-sizing: border-box; }
body { margin: 0; color: var(--ink); background: #fff; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif; line-height: 1.8; }
a { color: inherit; text-underline-offset: 5px; }
a:focus-visible, summary:focus-visible { outline: 3px solid var(--accent); outline-offset: 5px; }
.wrap { width: min(var(--width), calc(100% - 64px)); margin-inline: auto; }
.skip-link { position: absolute; top: -100px; background: white; padding: 12px; z-index: 2; }
.skip-link:focus { top: 8px; }
.site-header { min-height: 100px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 20px; font-size: 32px; font-weight: 850; letter-spacing: -.04em; text-decoration: none; }
.brand span { font-size: 12px; font-weight: 500; letter-spacing: .04em; }
nav { display: flex; gap: 30px; font-size: 14px; font-weight: 700; }
nav a { text-decoration: none; }
.hero { display: grid; grid-template-columns: 1.1fr 1fr; gap: 64px; align-items: center; padding-block: 80px 88px; }
.eyebrow { color: var(--accent); font-size: 13px; font-weight: 750; letter-spacing: .12em; margin: 0 0 20px; }
h1 { font-size: clamp(38px, 4.4vw, 58px); line-height: 1.45; letter-spacing: -.04em; margin: 0 0 24px; }
h1 span { color: var(--accent); }
.lead { font-size: 16px; color: var(--muted); line-height: 2; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.button { display: inline-flex; justify-content: center; align-items: center; gap: 28px; min-height: 52px; padding: 12px 26px; border: 1px solid var(--accent); border-radius: 6px; font-size: 14px; font-weight: 700; text-decoration: none; }
.primary { color: #fff; background: var(--accent); }
.primary:hover { background: #1044aa; }
.secondary { color: var(--accent); background: #fff; }
.secondary:hover { background: #edf3ff; }
.draft-note, .diagram-footnote { font-size: 12px; color: var(--muted); }
.draft-note { margin-top: 18px; }
.workflow { background: var(--pale); padding: 28px; border: 1px solid var(--line); border-radius: var(--radius); }
.diagram-label { display: flex; justify-content: space-between; gap: 10px; font-size: 10px; letter-spacing: .12em; font-weight: 700; margin: 0 0 26px; }
.diagram-label span { color: var(--muted); font-weight: 400; }
.marketplaces { display: flex; gap: 10px; }
.marketplaces span { flex: 1; padding: 10px 4px; text-align: center; font-weight: 700; background: #fff; border: 1px solid var(--line); border-radius: 6px; }
.connector { height: 26px; width: 1px; background: #9bb0c4; margin: auto; }
.workflow-core { background: var(--ink); color: #fff; border-radius: 8px; padding: 18px; text-align: center; }
.workflow-core strong { display: block; font-size: 32px; letter-spacing: .02em; line-height: 1.3; }
.workflow-core > span { font-size: 12px; color: #d9e6f3; }
.workflow-rows { margin-top: 18px; }
.workflow-rows > div { display: grid; grid-template-columns: 26px 1fr; column-gap: 10px; padding: 14px 0; border-bottom: 1px solid var(--line); }
.step-number { grid-row: span 2; color: var(--accent); font-size: 12px; padding-top: 3px; }
.workflow-rows strong { font-size: 14px; }
.workflow-rows div > span:last-child { color: var(--muted); font-size: 12px; }
.diagram-footnote { margin: 16px 0 0; font-size: 10px; }
.section { padding-block: 80px; }
h2 { margin: 0 0 36px; font-size: clamp(26px, 3vw, 34px); line-height: 1.6; letter-spacing: -.025em; }
h3 { font-size: 19px; margin: 12px 0; }
.features, .faq-section { background: var(--pale); }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 36px 40px; }
.feature-grid article, .feature-end { padding-top: 24px; border-top: 1px solid var(--line); }
.item-number, .flow-list li > span { color: var(--accent); font-size: 11px; letter-spacing: .1em; font-weight: 700; }
.feature-grid p, .flow-list p, .faq-list p, .contact-panel p { color: var(--muted); font-size: 14px; }
.feature-end > p { font-size: 24px; line-height: 1.6; color: var(--ink); margin: 8px 0 16px; }
.feature-end a { font-size: 13px; color: var(--accent); }
.flow-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; padding: 0; margin: 0; list-style: none; }
.flow-list li { padding-left: 22px; border-left: 2px solid var(--accent); }
.faq-layout { display: grid; grid-template-columns: 1fr 1.7fr; gap: 60px; }
.faq-list details { border-bottom: 1px solid var(--line); padding: 22px 0; }
.faq-list details:first-child { border-top: 1px solid var(--line); }
summary { cursor: pointer; font-size: 15px; font-weight: 700; padding-right: 10px; }
.faq-list p { margin-bottom: 0; }
.contact-panel { display: grid; grid-template-columns: 1.3fr 1fr; gap: 48px; border: 1px solid var(--line); border-radius: var(--radius); padding: 44px; }
.contact-panel h2 { margin-bottom: 12px; }
.contact-placeholder { border-left: 1px solid var(--line); padding-left: 36px; align-self: center; }
.placeholder-label { font-size: 11px; color: var(--muted); border: 1px solid var(--line); border-radius: 4px; padding: 4px 8px; }
.contact-panel .small { font-size: 12px; }
.site-footer { border-top: 1px solid var(--line); display: flex; align-items: center; gap: 24px; padding-block: 24px; }
.site-footer .brand { font-size: 24px; }
.site-footer p, .site-footer > span { font-size: 11px; color: var(--muted); }
.site-footer > span { margin-left: auto; }
/* スマホ: 列を縦に積み、操作と文章の幅を確保。 */
@media (max-width: 720px) {
  .wrap { width: calc(100% - 40px); }
  .site-header { min-height: 80px; gap: 12px; }
  .brand { font-size: 28px; }
  .brand span, .nav-feature { display: none; }
  .hero { grid-template-columns: 1fr; gap: 36px; padding-block: 44px 52px; }
  h1 { font-size: clamp(34px, 9vw, 48px); }
  .lead { font-size: 14px; }
  .desktop-break { display: none; }
  .actions { gap: 10px; }
  .actions .button { flex: 1; padding-inline: 12px; gap: 10px; white-space: nowrap; }
  .workflow { padding: 22px; }
  .section { padding-block: 52px; }
  .feature-grid, .flow-list, .faq-layout, .contact-panel { grid-template-columns: 1fr; gap: 26px; }
  .feature-end { padding-top: 18px; }
  .faq-layout { gap: 0; }
  .contact-panel { padding: 26px 22px; }
  .contact-placeholder { border-left: 0; border-top: 1px solid var(--line); padding: 26px 0 0; }
  .site-footer { flex-wrap: wrap; gap: 10px 18px; }
  .site-footer > span { margin-left: 0; }
}