:root {
  color-scheme: light;
  --paper: #f7f9fc;
  --surface: #ffffff;
  --ink: #0b1f3a;
  --muted: #55657c;
  --line: #cbd7e8;
  --green: #1d4ed8;
  --green-dark: #173b8f;
  --green-soft: #eaf2ff;
  --blue-bright: #3b82f6;
  --marker: #8cc8ff;
  --yellow: #f2c14e;
  --red: #b33a3a;
  --shadow: 0 14px 35px rgba(11, 31, 58, 0.1);
  --max: 1160px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Pretendard Variable", Pretendard, SUIT, "Noto Sans KR", sans-serif;
  line-height: 1.72;
  word-break: keep-all;
}
a { color: inherit; text-underline-offset: 0.22em; }
button, input, select { font: inherit; }
button { cursor: pointer; }
:focus-visible { outline: 3px solid var(--yellow); outline-offset: 3px; }
.skip-link { position: fixed; top: -5rem; left: 1rem; z-index: 100; padding: .7rem 1rem; background: var(--ink); color: white; }
.skip-link:focus { top: 1rem; }
.site-header { position: sticky; top: 0; z-index: 20; background: rgba(247, 249, 252, .94); border-bottom: 1px solid var(--line); backdrop-filter: blur(12px); }
.header-inner { width: min(calc(100% - 2rem), var(--max)); min-height: 72px; margin: auto; display: flex; align-items: center; justify-content: space-between; gap: 2rem; }
.brand { display: inline-flex; align-items: center; gap: .7rem; font-size: 1.15rem; font-weight: 850; text-decoration: none; letter-spacing: -.04em; }
.brand-mark { display: grid; place-items: center; width: 2rem; height: 2rem; color: white; background: var(--green); border-radius: 50% 50% 50% 12%; font-size: .9rem; }
.site-nav { display: flex; align-items: center; gap: 1.4rem; font-size: .94rem; font-weight: 650; }
.site-nav a { text-decoration: none; }
.site-nav a:hover { color: var(--green); }
.today-date { margin-left: auto; color: var(--green-dark); font-size: .82rem; font-weight: 760; white-space: nowrap; }
.menu-toggle { display: none; border: 1px solid var(--line); background: var(--surface); padding: .45rem .7rem; border-radius: .45rem; }
.page { width: min(calc(100% - 2rem), var(--max)); margin: 0 auto; }
.ledger { position: relative; padding-left: clamp(1rem, 4vw, 4.4rem); }
.ledger::before { content: ""; position: absolute; left: clamp(.25rem, 1.9vw, 1.8rem); top: 0; bottom: 0; width: 2px; background: var(--green); opacity: .6; }
.hero { min-height: 520px; display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(320px, .9fr); align-items: center; gap: clamp(2rem, 6vw, 6rem); padding-block: clamp(4rem, 9vw, 7rem); }
.hero h1, .page-hero h1 { margin: 0; max-width: 760px; font-size: clamp(2.8rem, 7.2vw, 6.4rem); line-height: .98; letter-spacing: -.075em; color: var(--ink); background: linear-gradient(118deg, #0b1f3a 4%, #173b8f 46%, #2563eb 78%, #3b82f6 100%); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.hero p, .page-hero p { max-width: 660px; margin: 1.8rem 0 0; color: var(--muted); font-size: clamp(1.05rem, 2vw, 1.28rem); }
.marker, .prose p > strong, .prose li > strong { padding: 0 .08em; color: var(--ink); background: linear-gradient(to top, rgba(140, 200, 255, .72) 0 38%, transparent 38% 100%); -webkit-box-decoration-break: clone; box-decoration-break: clone; }
.hero-tools { border-top: 3px solid var(--ink); border-bottom: 1px solid var(--ink); }
.hero-tools a { display: grid; grid-template-columns: 2.8rem 1fr auto; align-items: center; gap: .8rem; padding: 1.05rem 0; border-top: 1px solid var(--line); text-decoration: none; }
.hero-tools a:first-child { border-top: 0; }
.hero-tools a:hover strong { color: var(--green); }
.tool-index { font-variant-numeric: tabular-nums; color: var(--green); }
.tool-type { color: var(--muted); font-size: .88rem; }
.section { padding-block: clamp(3.5rem, 8vw, 6.5rem); border-top: 1px solid var(--line); }
.section-heading { display: grid; grid-template-columns: minmax(220px, .65fr) minmax(0, 1.35fr); gap: 2rem; margin-bottom: 2.5rem; }
.section-heading h2 { margin: 0; font-size: clamp(1.9rem, 4vw, 3.4rem); line-height: 1.08; letter-spacing: -.055em; }
.section-heading p { margin: .25rem 0 0; color: var(--muted); max-width: 680px; }
.tool-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); border-top: 2px solid var(--ink); }
.tool-card { min-height: 190px; padding: 1.5rem 1.2rem 1.5rem 0; border-bottom: 1px solid var(--line); text-decoration: none; }
.tool-card:nth-child(odd) { padding-right: 2rem; border-right: 1px solid var(--line); }
.tool-card:nth-child(even) { padding-left: 2rem; }
.tool-card h3 { margin: .5rem 0; font-size: 1.35rem; letter-spacing: -.035em; }
.tool-card p { margin: 0; color: var(--muted); }
.tool-card:hover h3 { color: var(--green); }
.tag { display: inline-block; color: var(--green-dark); font-size: .8rem; font-weight: 800; }
.page-hero { padding-block: clamp(4rem, 9vw, 7rem) clamp(2rem, 5vw, 4rem); }
.page-hero h1 { font-size: clamp(2.6rem, 6vw, 5.3rem); }
.breadcrumb { display: flex; gap: .55rem; margin-bottom: 1.4rem; color: var(--muted); font-size: .9rem; }
.breadcrumb a { color: var(--green-dark); }
.calculator-shell { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(300px, .85fr); gap: 0; margin-bottom: clamp(4rem, 8vw, 7rem); border: 1px solid var(--ink); background: var(--surface); box-shadow: var(--shadow); }
.mascot-guide { display: flex; align-items: center; gap: 1rem; min-width: 0; }
.calculator-shell > .mascot-guide { grid-column: 1 / -1; padding: .8rem clamp(1rem, 3vw, 2rem); border-bottom: 1px solid var(--line); background: #f5f9ff; }
.hero-side { display: grid; gap: 1.2rem; align-content: center; }
.home-mascot { max-width: 580px; }
.home-mascot .mascot-guide { align-items: flex-end; }
.mascot-figure { flex: 0 0 104px; width: 104px; filter: drop-shadow(0 12px 16px rgba(29, 78, 216, .2)); animation: mascot-float 3.4s ease-in-out infinite; transform-origin: 50% 80%; }
.home-mascot .mascot-figure { flex-basis: 126px; width: 126px; }
.mascot-svg { display: block; width: 100%; height: auto; overflow: visible; }
.mascot-body { fill: #2563eb; stroke: #0b1f3a; stroke-width: 4; }
.mascot-shine { fill: none; stroke: rgba(255, 255, 255, .78); stroke-linecap: round; stroke-width: 8; }
.mascot-antenna path, .mascot-arms path { fill: none; stroke: #0b1f3a; stroke-linecap: round; stroke-width: 5; }
.mascot-antenna circle { fill: #8cc8ff; stroke: #0b1f3a; stroke-width: 3; }
.mascot-eye { fill: white; stroke: #0b1f3a; stroke-width: 3; transform-box: fill-box; transform-origin: center; animation: mascot-blink 5.4s infinite; }
.mascot-pupil { fill: #0b1f3a; }
.mascot-mouth { fill: none; stroke: #0b1f3a; stroke-linecap: round; stroke-width: 4; }
.mascot-questions { fill: #1d4ed8; font-size: 31px; font-weight: 900; animation: question-drift 2.8s ease-in-out infinite alternate; }
.mascot-bubble { position: relative; max-width: 620px; padding: .85rem 1.05rem; border: 1px solid #8fb3ec; border-radius: 1rem 1rem 1rem .2rem; background: white; color: var(--ink); font-size: .93rem; font-weight: 690; box-shadow: 0 8px 20px rgba(23, 59, 143, .08); }
.mascot-bubble::before { content: ""; position: absolute; left: -9px; bottom: 10px; width: 16px; height: 16px; border-left: 1px solid #8fb3ec; border-bottom: 1px solid #8fb3ec; background: white; transform: rotate(45deg); }
.mascot-guide[data-mascot-state="result"] .mascot-figure { animation: mascot-result .65s cubic-bezier(.2, .8, .25, 1); }
.mascot-guide[data-mascot-state="result"] .mascot-mouth { d: path("M74 128 Q91 150 108 128"); }
.mascot-guide[data-mascot-state="error"] .mascot-body { fill: #6b8fdc; }
.mascot-guide[data-mascot-state="error"] .mascot-mouth { d: path("M80 141 Q91 126 102 141"); }
.mascot-guide[data-mascot-state="error"] .mascot-questions { fill: var(--red); }
.calculator-form { padding: clamp(1.4rem, 4vw, 3rem); }
.field-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.2rem; }
.field { display: grid; gap: .42rem; font-weight: 720; font-size: .92rem; }
.input-wrap { display: grid; grid-template-columns: 1fr auto; align-items: center; border: 1px solid var(--line); background: var(--paper); }
.input-wrap:focus-within { border-color: var(--green); box-shadow: 0 0 0 3px rgba(23, 107, 69, .13); }
.input-wrap input { width: 100%; min-width: 0; padding: .85rem .7rem; border: 0; outline: 0; background: transparent; color: var(--ink); font-weight: 760; font-variant-numeric: tabular-nums; }
.input-wrap span { padding-right: .8rem; color: var(--muted); font-size: .85rem; }
.field select { padding: .82rem .7rem; border: 1px solid var(--line); background: var(--paper); color: var(--ink); }
.primary-button { margin-top: 1.5rem; width: 100%; border: 0; background: var(--green); color: white; padding: .95rem 1.2rem; font-weight: 800; }
.primary-button:hover { background: var(--green-dark); }
.form-error { color: var(--red); font-weight: 700; margin: 1rem 0 0; }
.receipt { position: relative; padding: clamp(1.5rem, 4vw, 3rem); background: var(--green-soft); border-left: 1px dashed var(--green); }
.receipt::after { content: ""; position: absolute; inset: .75rem; border: 1px solid rgba(29, 78, 216, .22); pointer-events: none; }
.receipt-label { position: relative; z-index: 1; margin: 0 0 1.4rem; font-weight: 850; color: var(--green-dark); }
.receipt dl { position: relative; z-index: 1; margin: 0; }
.receipt dl div { display: flex; justify-content: space-between; gap: 1.5rem; padding: .78rem 0; border-bottom: 1px dotted rgba(11, 31, 58, .35); }
.receipt dt { color: var(--muted); }
.receipt dd { margin: 0; text-align: right; font-weight: 800; font-variant-numeric: tabular-nums; }
.receipt .receipt-total { margin-top: .7rem; border-top: 2px solid var(--ink); border-bottom: 0; font-size: 1.15rem; }
.receipt-empty, .result-note { position: relative; z-index: 1; color: var(--muted); }
.result-note { margin: 1.5rem 0 0; font-size: .8rem; }
.article-grid { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(230px, .5fr); gap: clamp(2rem, 6vw, 6rem); align-items: start; }
.prose { max-width: 760px; }
.prose h2 { margin: 3.3rem 0 1rem; font-size: clamp(1.7rem, 3vw, 2.5rem); line-height: 1.2; letter-spacing: -.045em; }
.prose h2:first-child { margin-top: 0; }
.prose h3 { margin: 2rem 0 .6rem; font-size: 1.2rem; }
.prose p, .prose li { color: #334762; }
.prose strong { color: var(--ink); }
.formula { margin: 1.4rem 0; padding: 1.2rem 1.4rem; border-left: 4px solid var(--green); background: var(--green-soft); font-weight: 760; overflow-wrap: anywhere; }
.notice { padding: 1rem 1.2rem; border: 1px solid #d9a800; background: #fff8d7; }
.toc { position: sticky; top: 100px; padding: 1.4rem; border-top: 3px solid var(--ink); background: var(--surface); }
.toc strong { display: block; margin-bottom: .7rem; }
.toc a { display: block; padding: .35rem 0; color: var(--muted); font-size: .9rem; }
.faq details { border-top: 1px solid var(--line); padding: 1rem 0; }
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary { cursor: pointer; font-weight: 800; }
.faq p { margin-bottom: 0; }
.related-links { display: flex; flex-wrap: wrap; gap: .7rem; }
.related-links a { padding: .6rem .9rem; border: 1px solid var(--line); background: var(--surface); text-decoration: none; font-weight: 700; }
.site-footer { margin-top: 5rem; background: var(--ink); color: #edf4ef; }
.footer-inner { width: min(calc(100% - 2rem), var(--max)); margin: auto; padding: 3.2rem 0; display: grid; grid-template-columns: 1fr auto; gap: 2rem; }
.footer-inner p { color: #b9c7be; max-width: 520px; }
.footer-links { display: grid; grid-template-columns: repeat(2, auto); gap: .5rem 1.4rem; align-content: start; }
.footer-links a { color: #edf4ef; }
.copyright { grid-column: 1 / -1; padding-top: 1.2rem; border-top: 1px solid #465149; font-size: .82rem; color: #9eaca3; }

@keyframes mascot-float {
  0%, 100% { transform: translateY(0) rotate(-1deg); }
  50% { transform: translateY(-7px) rotate(1deg); }
}

@keyframes mascot-blink {
  0%, 46%, 52%, 100% { transform: scaleY(1); }
  48%, 50% { transform: scaleY(.08); }
}

@keyframes question-drift {
  from { transform: translateY(0); opacity: .55; }
  to { transform: translateY(-7px); opacity: 1; }
}

@keyframes mascot-result {
  0% { transform: translateY(0) scale(1); }
  42% { transform: translateY(-15px) scale(1.05); }
  72% { transform: translateY(2px) scale(.98); }
  100% { transform: translateY(0) scale(1); }
}

@media (max-width: 800px) {
  .menu-toggle { display: block; }
  .site-nav { display: none; position: absolute; top: 72px; left: 0; right: 0; padding: 1rem; background: var(--surface); border-bottom: 1px solid var(--line); }
  .site-nav[data-open] { display: grid; }
  .hero, .calculator-shell, .article-grid, .section-heading { grid-template-columns: 1fr; }
  .hero { min-height: auto; }
  .field-grid { grid-template-columns: 1fr; }
  .receipt { border-left: 0; border-top: 1px dashed var(--green); min-height: 260px; }
  .toc { position: static; order: -1; }
  .today-date { margin-left: auto; font-size: .75rem; }
}

@media (max-width: 560px) {
  body { line-height: 1.65; }
  .ledger { padding-left: 1rem; }
  .ledger::before { left: .15rem; }
  .tool-list { grid-template-columns: 1fr; }
  .tool-card:nth-child(odd), .tool-card:nth-child(even) { padding: 1.3rem 0; border-right: 0; }
  .footer-inner { grid-template-columns: 1fr; }
  .copyright { grid-column: 1; }
  .today-date { position: absolute; top: 48px; left: 4.6rem; font-size: .68rem; }
  .calculator-shell > .mascot-guide { align-items: flex-end; padding: .7rem .85rem; }
  .mascot-figure { flex-basis: 78px; width: 78px; }
  .home-mascot .mascot-figure { flex-basis: 94px; width: 94px; }
  .mascot-bubble { padding: .7rem .8rem; font-size: .84rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .mascot-figure, .mascot-eye, .mascot-questions { animation: none !important; }
}