:root {
  --fg: #1b1b1b;
  --muted: #555;
  --bg: #fff;
  --accent: #0b5f8a;
  --accent-soft: #eef5f9;
  --line: #d4d9dd;
  --err: #1b1b1b;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font-family: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic UI", "Yu Gothic", Meiryo, "Noto Sans CJK JP", "Noto Sans JP", sans-serif;
  font-size: 1rem; line-height: 1.8; overflow-wrap: anywhere;
}
.wrap { max-width: 42rem; margin: 0 auto; padding: 0 1rem; }
a { color: var(--accent); text-underline-offset: 0.18em; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; }
.skip { position: absolute; left: -999px; top: 0; background: var(--bg); padding: .5rem 1rem; z-index: 10; }
.skip:focus { left: 0; }

.site-header { border-bottom: 1px solid var(--line); }
.header-inner { display: flex; flex-wrap: wrap; align-items: baseline; justify-content: space-between; gap: .25rem 1rem; padding-top: .75rem; padding-bottom: .75rem; }
.brand { font-weight: 700; font-size: 1.125rem; color: var(--fg); text-decoration: none; }
.site-header nav { display: flex; flex-wrap: wrap; gap: .25rem 1rem; }
.site-header nav a { color: var(--fg); text-decoration: none; padding: .25rem 0; border-bottom: 2px solid transparent; }
.site-header nav a:hover, .site-header nav a[aria-current="page"] { border-bottom-color: var(--accent); }

main { padding-top: 1.5rem; padding-bottom: 2.5rem; }
h1 { font-size: 1.625rem; line-height: 1.4; margin: 0 0 .5rem; }
h2 { font-size: 1.25rem; line-height: 1.5; margin: 2rem 0 .5rem; }
h3 { font-size: 1.0625rem; line-height: 1.5; margin: 1.5rem 0 .25rem; }
p { margin: .5rem 0 .75rem; }
ul, ol { padding-left: 1.4rem; margin: .5rem 0 .75rem; }
.lead { color: var(--muted); margin-bottom: 1.25rem; }

.tool { border: 1px solid var(--line); border-top: 4px solid var(--accent); border-radius: 4px; padding: .5rem 1rem 1rem; margin: 1.25rem 0; }
.tool h2 { margin-top: .75rem; }
.field { margin: .9rem 0; }
.field > label, .field > .label, legend { display: block; font-weight: 700; margin-bottom: .25rem; padding: 0; }
fieldset { border: 0; margin: .9rem 0; padding: 0; min-width: 0; }
.row { display: flex; flex-wrap: wrap; gap: .5rem; align-items: center; }
input[type="text"], input[type="date"], input[type="number"], select, textarea {
  font: inherit; color: var(--fg); background: var(--bg);
  border: 1px solid #8a949b; border-radius: 4px; padding: .45rem .6rem;
  width: 100%; max-width: 100%; min-height: 2.75rem; line-height: 1.5;
}
.row input[type="date"] { width: auto; flex: 1 1 11rem; min-width: 0; }
textarea { min-height: 12rem; resize: vertical; }
.choice { display: flex; align-items: flex-start; gap: .5rem; margin: .25rem 0; }
.choice input { margin: .45rem 0 0; width: 1.1rem; height: 1.1rem; flex: none; accent-color: var(--accent); }
.choice label { font-weight: 400; }
.inline-choices { display: flex; flex-wrap: wrap; gap: .25rem 1.5rem; }
button {
  font: inherit; min-height: 2.75rem; padding: .35rem 1rem; cursor: pointer;
  color: var(--accent); background: var(--bg); border: 1px solid var(--accent); border-radius: 4px;
}
button:hover { background: var(--accent-soft); }
.hint { color: var(--muted); font-size: .9375rem; margin: .25rem 0 0; }
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 0 1rem; }
@media (max-width: 30rem) { .grid2 { grid-template-columns: 1fr; } }

.result { background: var(--accent-soft); border-left: 4px solid var(--accent); padding: .6rem 1rem; margin-top: 1rem; min-height: 3.5rem; }
.result p { margin: .15rem 0; }
.result .big { font-size: 1.75rem; font-weight: 700; line-height: 1.4; }
.result .msg { color: var(--fg); }
.result .error { font-weight: 700; }
.result dl { margin: .25rem 0; display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: .15rem 1rem; }
.result dt { font-weight: 400; }
.result dd { margin: 0; font-weight: 700; text-align: right; font-variant-numeric: tabular-nums; }
.result dl[hidden], .result [hidden] { display: none; }

.prose { margin-top: 2rem; }
.note { border-top: 1px solid var(--line); padding-top: .75rem; margin-top: 1.5rem; color: var(--muted); font-size: .9375rem; }

.tool-list { list-style: none; padding: 0; margin: 1.25rem 0; }
.tool-list li { border: 1px solid var(--line); border-left: 4px solid var(--accent); border-radius: 4px; margin: .75rem 0; padding: .6rem 1rem; }
.tool-list a { font-weight: 700; font-size: 1.125rem; }
.tool-list p { margin: .15rem 0 0; color: var(--muted); }

.site-footer { border-top: 1px solid var(--line); padding: 1rem 0 2rem; font-size: .9375rem; color: var(--muted); }
.site-footer p { margin: 0; }