:root {
  --ink: #173147;
  --muted: #617283;
  --white: #fff;
  --canvas: #f3f8fb;
  --blue-soft: #eaf6fb;
  --blue: #1b7392;
  --blue-dark: #14566f;
  --nurse: #d96878;
  --nurse-dark: #a93f51;
  --nurse-soft: #fff0f3;
  --line: #dce8ef;
  --shadow: 0 14px 38px rgba(37, 85, 113, .08);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans JP", sans-serif;
  font-size: 16px;
  line-height: 1.8;
}
a { color: var(--blue); }
.nowrap { white-space: nowrap; }
.container { width: min(100% - 32px, 1040px); margin-inline: auto; }
.article-width { max-width: 820px; }

.topbar { border-bottom: 1px solid var(--line); background: rgba(255,255,255,.96); }
.topbar-inner { display: flex; min-height: 68px; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; }
.brand img { display: block; width: 172px; height: auto; }
.head-link { position: relative; padding-right: 19px; color: var(--ink); font-size: 14px; font-weight: 700; text-decoration: none; }
.head-link::after { content: ""; position: absolute; right: 2px; top: 42%; width: 7px; height: 7px; border-right: 2px solid var(--blue); border-bottom: 2px solid var(--blue); transform: rotate(45deg); }

.article-hero { padding: 42px 0 46px; background: linear-gradient(180deg, #f5fbfe 0%, #fff 100%); }
.kicker { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 0 0 12px; color: var(--muted); font-size: 13px; font-weight: 700; }
.cluster-mark { display: grid; width: 28px; height: 28px; place-items: center; border-radius: 50%; color: var(--white); background: var(--nurse); }
.cluster-mark svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.type-badge { display: inline-flex; align-items: center; gap: 4px; min-height: 23px; padding: 4px 8px; border-radius: 999px; color: var(--blue-dark); background: var(--blue-soft); font-size: 12px; line-height: 1; }
.type-badge svg { width: 12px; height: 12px; fill: none; stroke: currentColor; stroke-width: 1.4; stroke-linecap: round; stroke-linejoin: round; }
h1 { max-width: 15em; margin: 0; font-size: clamp(37px, 7vw, 55px); line-height: 1.18; letter-spacing: -.045em; }
.title-break { display: block; }
.lead { max-width: 40em; margin: 17px 0 0; color: var(--muted); font-size: 16px; }

.image-slot {
  display: grid;
  min-height: 250px;
  align-items: end;
  margin: 52px 0 0;
  padding: 18px;
  overflow: hidden;
  border-radius: 22px;
  background-image: var(--article-image), linear-gradient(135deg, var(--blue-soft), var(--nurse-soft));
  background-position: center;
  background-size: cover;
  box-shadow: var(--shadow);
}
.image-slot-hero { min-height: 300px; margin-top: 25px; }
.image-slot figcaption { width: fit-content; max-width: 90%; padding: 7px 11px; border-radius: 10px; color: var(--ink); background: rgba(255,255,255,.9); font-size: 13px; font-weight: 700; }
.image-slot-caption-right { justify-items: end; }
.article-body > .image-slot + section { padding-top: 28px; }

.answer-card { margin-top: 26px; padding: 19px; border-radius: 22px; background: var(--white); box-shadow: var(--shadow); }
.answer-label { margin: 0 0 11px; color: var(--blue-dark); font-size: 13px; font-weight: 750; }
.answer-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 11px; }
.answer-item { display: grid; grid-template-columns: 48px 1fr; gap: 12px; align-items: center; min-width: 0; padding: 14px; border-radius: 16px; background: var(--canvas); }
.answer-item p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.65; }
.answer-item strong { color: var(--ink); }
.answer-icon { display: grid; width: 48px; height: 48px; place-items: center; border-radius: 15px; color: var(--nurse-dark); background: var(--nurse-soft); font-size: 16px; font-weight: 800; line-height: 1; }
.answer-item:last-child .answer-icon { font-size: 12px; }

.article-body { padding-bottom: 68px; }
.article-body > section { padding: 62px 0 4px; }
.article-body h2 { max-width: 22em; margin: 0 0 17px; font-size: clamp(26px, 5vw, 34px); line-height: 1.35; letter-spacing: -.035em; }
.article-body h3, .article-body h4 { line-height: 1.45; }
.article-body p { margin: 0 0 14px; }
.section-number { margin: 0 0 4px !important; color: var(--nurse); font-size: 13px; font-weight: 800; letter-spacing: .1em; }
.note-box { margin-top: 20px !important; padding: 14px 16px; border-radius: 14px; color: var(--muted); background: var(--blue-soft); font-size: 14px; }

.shift-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin-top: 25px; }
.shift-heading { display: flex; min-height: 50px; align-items: center; gap: 10px; margin: 0 0 11px; font-size: 16px; }
.shift-heading > span { flex: 0 0 auto; padding: 5px 9px; border-radius: 999px; color: var(--white); background: var(--nurse); font-size: 12px; }
.shift-heading.three > span { background: var(--blue); }
.hospital-card { margin-bottom: 12px; padding: 16px; border-radius: 18px; background: var(--canvas); }
.hospital-card h4 { margin: 0 0 10px; font-size: 16px; }
.shift-row { display: grid; grid-template-columns: 52px 1fr; align-items: center; gap: 8px; margin-top: 6px; padding: 7px 10px; border-radius: 10px; background: var(--white); font-size: 14px; }
.shift-row > span { color: var(--muted); font-size: 12px; font-weight: 700; }
.shift-row strong { font-variant-numeric: tabular-nums; }
.shift-row.night { border-left: 4px solid var(--nurse); }
.shift-row.evening { border-left: 4px solid #6f98d8; }
.shift-row.deep { border-left: 4px solid var(--blue-dark); }
.hospital-card a { display: inline-block; margin-top: 10px; font-size: 13px; font-weight: 700; }
.checked-date { color: var(--muted); font-size: 13px; }

.timeline-diagram { margin: 25px 0; padding: 20px; border-radius: 20px; background: var(--canvas); }
.timeline-scale { display: grid; grid-template-columns: repeat(5, 1fr); margin: 0 0 10px 82px; color: var(--muted); font-size: 11px; text-align: center; }
.timeline-row { display: grid; grid-template-columns: 70px minmax(0, 1fr); gap: 12px; align-items: center; margin-top: 10px; }
.timeline-row > strong { font-size: 13px; }
.timeline-track { position: relative; height: 36px; border-radius: 12px; background: repeating-linear-gradient(90deg, var(--white) 0, var(--white) calc(25% - 1px), var(--line) calc(25% - 1px), var(--line) 25%); }
.timeline-bar { position: absolute; top: 5px; display: grid; height: 26px; place-items: center; overflow: hidden; border-radius: 9px; color: var(--white); font-size: 11px; font-weight: 800; white-space: nowrap; }
.two-shift { left: 18.75%; width: 68.75%; background: var(--nurse); }
.evening-shift { left: 11.5%; width: 35.5%; background: #6f98d8; }
.deep-shift { left: 45.8%; width: 38.6%; background: var(--blue-dark); }
.timeline-diagram > p { margin: 13px 0 0; color: var(--muted); font-size: 12px; text-align: right; }
.subheading { margin: 34px 0 12px; font-size: 21px; }

.number-compare { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 24px 0 11px; }
.number-card { padding: 20px; border-radius: 18px; background: var(--canvas); }
.number-card > span { display: block; color: var(--muted); font-size: 13px; font-weight: 700; }
.number-card strong { display: block; margin-top: 2px; color: var(--nurse-dark); font-size: clamp(31px, 7vw, 42px); line-height: 1.3; letter-spacing: -.04em; }
.number-card small { color: var(--muted); }
.number-source { color: var(--muted); font-size: 13px; }

.average-diagram { margin: 24px 0; padding: 22px; border-radius: 20px; background: var(--canvas); }
.diagram-label { margin: 0 0 14px; color: var(--muted); font-size: 12px; font-weight: 700; text-align: center; }
.average-people, .average-operation { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 8px; }
.average-people span, .average-operation span { padding: 8px 11px; border-radius: 10px; background: var(--white); font-size: 13px; font-weight: 700; text-align: center; }
.average-people b, .average-operation b { color: var(--nurse); }
.average-operation { margin: 16px auto; }
.average-operation::before { content: "↓"; width: 100%; color: var(--blue); font-size: 20px; text-align: center; }
.average-result { display: grid; width: min(100%, 310px); justify-items: center; margin: 0 auto; padding: 16px; border-radius: 16px; color: var(--white); background: var(--blue); }
.average-result small { opacity: .88; }
.average-result strong { font-size: 28px; line-height: 1.35; }
.fact-callout { display: flex; align-items: center; gap: 18px; margin: 22px 0; padding: 18px 20px; border-radius: 18px; background: var(--nurse-soft); }
.fact-callout > strong { flex: none; color: var(--nurse-dark); font-size: clamp(38px, 7vw, 54px); line-height: 1; }
.fact-callout p { margin: 0; }

.mini-flow { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-top: 23px; }
.mini-flow > div { padding: 17px; border-radius: 17px; background: var(--canvas); }
.mini-flow span { display: grid; width: 28px; height: 28px; place-items: center; margin-bottom: 10px; border-radius: 50%; color: var(--white); background: var(--blue); font-size: 12px; font-weight: 800; }
.mini-flow p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.65; }
.mini-flow strong { color: var(--ink); }

.check-list { display: grid; gap: 9px; margin: 22px 0 0; padding: 0; list-style: none; }
.check-list li { display: grid; grid-template-columns: 38px 1fr; gap: 12px; align-items: center; padding: 15px 16px; border-radius: 15px; background: var(--canvas); }
.check-list li > span { color: var(--nurse); font-size: 12px; font-weight: 800; }
.check-list strong { display: block; }
.check-list p { margin: 1px 0 0; color: var(--muted); font-size: 14px; line-height: 1.55; }

.tool-links { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 22px; }
.tool-links > a { position: relative; display: grid; grid-template-columns: 45px minmax(0,1fr) 12px; gap: 12px; align-items: center; min-width: 0; min-height: 110px; padding: 16px; border-radius: 18px; color: var(--ink); background: var(--blue-soft); text-decoration: none; }
.tool-link-icon { display: grid; width: 45px; height: 45px; place-items: center; border-radius: 14px; color: var(--nurse-dark); background: var(--white); }
.tool-link-icon svg { width: 26px; height: 26px; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.tool-links strong { display: block; line-height: 1.5; }
.tool-links small { display: block; margin-top: 4px; color: var(--muted); line-height: 1.5; }
.tool-links i { width: 9px; height: 9px; border-right: 2px solid var(--blue); border-bottom: 2px solid var(--blue); transform: rotate(-45deg); }

.source-section > p { color: var(--muted); }
.source-section details { border-bottom: 1px solid var(--line); }
.source-section summary { position: relative; min-height: 62px; padding: 15px 42px 15px 0; color: var(--ink); cursor: pointer; font-weight: 700; list-style: none; }
.source-section summary::-webkit-details-marker { display: none; }
.source-section summary::after { content: "+"; position: absolute; top: 50%; right: 6px; color: var(--nurse); font-size: 23px; font-weight: 400; transform: translateY(-50%); }
.source-section details[open] summary::after { content: "−"; }
.details-body { padding: 0 0 25px; color: var(--muted); }
.formula { display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 8px; margin: 20px 0; padding: 17px; border-radius: 15px; color: var(--ink); background: var(--canvas); text-align: center; }
.formula span, .formula strong { padding: 5px 8px; border-radius: 8px; background: var(--white); }
.formula b { color: var(--nurse); }
.source-list p { margin: 7px 0; }
.detail-note { font-size: 13px; }

.site-foot { padding: 30px 0; color: var(--muted); background: var(--canvas); font-size: 13px; }
.foot-links { display: flex; flex-wrap: wrap; gap: 16px; margin-bottom: 9px; }
.foot-links a { color: var(--ink); }
.site-foot p { margin: 0; }

a:focus-visible, summary:focus-visible { outline: 3px solid rgba(27,115,146,.3); outline-offset: 3px; }

@media (max-width: 700px) {
  .container { width: min(100% - 24px, 1040px); }
  .article-hero { padding: 29px 0 34px; }
  h1 { font-size: clamp(32px, 9.5vw, 42px); }
  .image-slot { min-height: 210px; margin-top: 38px; padding: 13px; }
  .image-slot-hero { min-height: 230px; margin-top: 21px; }
  .answer-grid, .shift-columns, .mini-flow, .tool-links { grid-template-columns: 1fr; }
  .answer-item { grid-template-columns: 43px 1fr; }
  .answer-icon { width: 43px; height: 43px; }
  .article-body > section { padding-top: 48px; }
  .number-card { padding: 16px 13px; }
  .number-card strong { font-size: clamp(29px, 8.5vw, 38px); }
  .timeline-diagram { padding: 14px 11px; }
  .timeline-scale { margin-left: 59px; font-size: 9px; }
  .timeline-row { grid-template-columns: 51px minmax(0,1fr); gap: 8px; }
  .timeline-row > strong { font-size: 12px; }
  .timeline-bar { font-size: 10px; }
  .average-diagram { padding: 17px 12px; }
  .fact-callout { align-items: flex-start; flex-direction: column; gap: 9px; }
}

@media (max-width: 360px) {
  .brand img { width: 152px; }
  .head-link { font-size: 12px; }
  h1 { font-size: 32px; }
  .answer-card { padding: 13px; }
  .answer-item { padding: 12px; }
  .number-compare { grid-template-columns: 1fr; }
  .hospital-card { padding: 14px; }
  .shift-row { grid-template-columns: 45px 1fr; padding-inline: 8px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}