:root {
  font-family: Meiryo, "Yu Gothic", system-ui, sans-serif;
  color: #202b33;
  background: #fff;
  font-size: 16px;
  line-height: 1.7;
  --accent: #155f78;
  --ink: #202b33;
  --muted: #53616a;
  --line: #d6dee0;
  --wash: #f6f9fa;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; }
a { color: var(--accent); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
button, input { font: inherit; }
h1, h2, h3, p { margin: 0; }
h1, h2, h3 { color: var(--ink); }
h1 { font-size: clamp(2rem, 3.1vw, 2.65rem); line-height: 1.35; letter-spacing: -.035em; }
h2 { font-size: 1.35rem; line-height: 1.45; letter-spacing: -.02em; }
h3 { font-size: 1.06rem; line-height: 1.5; }
p + p { margin-top: 1em; }
ul { padding-left: 1.25em; }
li { margin: .3em 0; }
.shell { max-width: 1160px; margin-inline: auto; padding-inline: 30px; }
.skip { position: absolute; top: -100px; left: 10px; z-index: 2; padding: 10px; background: #fff; }
.skip:focus { top: 10px; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); }
[hidden] { display: none !important; }

header { border-bottom: 1px solid var(--line); }
header .shell { display: flex; align-items: center; justify-content: space-between; gap: 22px; min-height: 72px; }
.brand { color: var(--ink); font-size: 1.16rem; font-weight: 700; text-decoration: none; white-space: nowrap; letter-spacing: -.025em; }
.brand small { display: inline-block; margin-left: .4em; padding-left: .65em; border-left: 1px solid var(--line); color: var(--muted); font-size: .76rem; font-weight: 400; letter-spacing: 0; }
nav { display: flex; flex-wrap: wrap; column-gap: 22px; row-gap: 3px; font-size: .88rem; }
nav a { color: var(--ink); text-decoration: none; }
nav a:hover { color: var(--accent); text-decoration: underline; }

main { padding-top: 32px; }
.draft { width: fit-content; margin: 17px 0 22px; padding-top: 9px; border-top: 1px solid var(--line); color: var(--muted); font-size: .83rem; line-height: 1.5; }
.intro { max-width: 770px; }
.eyebrow { margin-bottom: 7px; color: var(--accent); font-size: .83rem; font-weight: 700; letter-spacing: .035em; }
.intro > p:last-child { max-width: 720px; margin-top: 11px; color: var(--muted); font-size: 1rem; line-height: 1.75; }
.layout { display: grid; grid-template-columns: minmax(295px, 340px) minmax(0, 1fr); align-items: start; gap: 36px; border-top: 2px solid var(--ink); padding-top: 22px; }
.layout > * { min-width: 0; }
.panel { border: 1px solid var(--line); border-radius: 2px; background: var(--wash); padding: 22px 24px 24px; }
.panel h2, .result h2 { margin-bottom: 14px; }
.panel label { display: block; margin: 12px 0 4px; font-size: .88rem; font-weight: 700; line-height: 1.5; }
.panel label span { float: right; color: var(--muted); font-size: .81rem; font-weight: 400; }
.panel input { display: block; width: 100%; height: 44px; padding: 8px 11px; border: 1px solid #aab8be; border-radius: 2px; background: #fff; color: var(--ink); font-variant-numeric: tabular-nums; }
.panel input:focus { border-color: var(--accent); }
.panel input::placeholder { color: #697881; opacity: 1; }
.hint { color: var(--muted); font-size: .84rem; line-height: 1.65; }
.panel .hint { margin: 5px 0 9px; }
.advanced { margin-top: 13px; border-top: 1px solid var(--line); }
.advanced summary { padding: 11px 0 2px; color: var(--accent); font-size: .86rem; font-weight: 700; line-height: 1.4; cursor: pointer; }
.advanced summary span { display: block; margin: 4px 0 0 19px; color: var(--muted); font-size: .77rem; font-weight: 400; }
.advanced-fields { padding-top: 5px; }.panel button { display: block; width: 100%; min-height: 46px; margin-top: 18px; padding: 9px 16px; border: 1px solid var(--accent); border-radius: 2px; background: var(--accent); color: #fff; font-weight: 700; cursor: pointer; }
.panel button:hover { background: #104c61; }
.error { margin-top: 10px; color: #9a2b26; font-size: .9rem; }
.result { min-width: 0; padding: 4px 0 0; }
.result-head { display: flex; align-items: baseline; justify-content: space-between; flex-wrap: wrap; gap: 4px 20px; }
.result-head h2 { margin-bottom: 0; }
.tag { color: var(--muted); font-size: .78rem; }
.result-context { margin-top: 17px; color: var(--muted); font-size: .76rem; font-weight: 700; letter-spacing: .06em; }
#scenario { margin-top: 2px; font-size: .95rem; line-height: 1.6; }
.table-scroll { max-width: 100%; overflow-x: auto; overscroll-behavior-inline: contain; margin: 18px 0 0; border-top: 1px solid var(--ink); border-bottom: 1px solid var(--line); scrollbar-color: #8ca3aa #e9eef0; }
table { width: 100%; min-width: 620px; border-collapse: collapse; text-align: left; font-size: .89rem; }
caption { padding: 0 0 7px; color: var(--muted); text-align: left; font-size: .83rem; }
th, td { padding: 12px 9px; border-bottom: 1px solid var(--line); vertical-align: top; }
tr:last-child td { border-bottom: 0; }
th { color: var(--muted); font-size: .78rem; font-weight: 700; white-space: nowrap; }
td:nth-child(2), td:nth-child(3), td:nth-child(4) { font-variant-numeric: tabular-nums; white-space: nowrap; }
td:nth-child(4) { color: var(--accent); font-size: 1.01rem; font-weight: 700; }
.notice { margin: 10px 0; padding: 10px 12px; border-left: 3px solid var(--accent); background: var(--wash); font-size: .88rem; }
#break-even { margin: 13px 0 0; padding: 11px 0 0; border-top: 1px solid var(--line); color: var(--ink); font-size: .9rem; }
.assumptions { margin-top: 20px; padding-top: 16px; border-top: 1px solid var(--line); color: var(--muted); font-size: .83rem; }
.assumptions h3 { font-size: .88rem; }
.assumptions ul { margin: 8px 0 0; }
.assumptions li { margin: .35em 0; }

.reading { margin-top: 54px; }
.reading h2 { margin-bottom: 14px; }
.cards { border-top: 1px solid var(--ink); }
.cards > a { display: grid; grid-template-columns: minmax(0, 1fr) auto; column-gap: 24px; padding: 19px 2px; border-bottom: 1px solid var(--line); color: var(--ink); text-decoration: none; }
.cards h3 { grid-column: 1; }
.cards p { grid-column: 1; margin-top: 5px; color: var(--muted); font-size: .9rem; }
.cards span { grid-column: 2; grid-row: 1 / 3; align-self: center; color: var(--accent); font-size: .88rem; white-space: nowrap; text-decoration: underline; text-underline-offset: 3px; }
.cards > a:hover h3 { color: var(--accent); }
.sources { max-width: 900px; margin-top: 54px; padding-top: 20px; border-top: 1px solid var(--ink); font-size: .88rem; }
.sources h2 { margin-bottom: 9px; }
.sources p { color: var(--muted); }
.sources ul { display: flex; flex-wrap: wrap; gap: 4px 28px; margin: 12px 0 0; }
.sources li { padding-right: 6px; }
footer { margin-top: 52px !important; padding-top: 18px !important; padding-bottom: 28px !important; border-top: 1px solid var(--line); color: var(--muted); font-size: .84rem; }
footer p { margin: 0; }

.article { max-width: 810px; }
.article .draft { margin: 0 0 25px; }
.article .lead { margin-top: 16px; color: #34424b; font-size: 1.08rem; line-height: 1.85; }
.article > p:not(.draft,.eyebrow,.lead,.hint) { margin-top: 15px; }
.article h2 { margin-top: 40px; padding-top: 12px; border-top: 1px solid var(--line); }
.article h2 + p { margin-top: 10px; }
.article ul { margin-top: 10px; }
.article .table-scroll { margin-top: 16px; }
.article table { min-width: 500px; }
.article .sources { margin-top: 46px; }
.article .sources h2 { margin: 0; padding: 0; border: 0; }
.guide-comparison { margin-top: 16px; border-top: 1px solid var(--ink); }
.guide-comparison > div { padding: 17px 0; border-bottom: 1px solid var(--line); }
.guide-comparison h3 { margin-bottom: 5px; }
.guide-comparison p { color: var(--muted); }
.guide-next { margin-top: 40px; padding: 0 0 22px; border-bottom: 1px solid var(--line); }
.article .guide-next h2 { margin-top: 0; border-top: 2px solid var(--ink); }
.guide-cta { display: inline-block; margin-top: 4px; padding: 11px 16px; border: 1px solid var(--accent); background: var(--accent); color: #fff; font-weight: 700; line-height: 1.5; text-decoration: none; }
.guide-cta:hover { background: #104c61; }

@media (max-width: 850px) {
  .shell { padding-inline: 22px; }
  header .shell { display: block; padding-block: 13px 11px; }
  nav { margin-top: 8px; column-gap: 19px; }
  .layout { grid-template-columns: minmax(255px, 300px) minmax(0, 1fr); gap: 22px; }
  .panel { padding: 17px; }
}
@media (max-width: 680px) {
  .shell { padding-inline: 18px; }
  main { padding-top: 21px; }
  .intro > p:last-child { font-size: .94rem; line-height: 1.65; }
  .draft { margin: 13px 0 18px; font-size: .77rem; }
  .layout { display: block; padding-top: 15px; }
  .panel { padding: 17px 17px 18px; }
  .panel h2, .result h2 { font-size: 1.23rem; }
  .panel label { margin-top: 10px; }
  .panel .hint { margin-bottom: 7px; }
  .result { margin-top: 28px; padding-top: 14px; border-top: 2px solid var(--ink); }
  .table-scroll::before { content: "表は左右にスクロールできます →"; display: block; padding: 8px 9px 4px; color: var(--accent); font-size: .81rem; }
  .result table { min-width: 650px; }
  .result th:first-child, .result td:first-child { position: sticky; left: 0; z-index: 1; min-width: 137px; background: #fff; box-shadow: 1px 0 0 var(--line); }
  .result th:first-child { z-index: 2; }
  .reading, .sources { margin-top: 40px; }
  .cards > a { display: block; padding: 15px 1px; }
  .cards span { display: inline-block; margin-top: 10px; }
  .article h2 { margin-top: 32px; }
  footer { margin-top: 42px !important; }
}
@media (max-width: 420px) {
  .brand { font-size: 1.07rem; }
  .brand small { font-size: .72rem; }
  nav { column-gap: 14px; font-size: .84rem; }
  h1 { font-size: 1.9rem; }
  .tag { font-size: .76rem; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }