:root {
  --ink: #17232f;
  --muted: #5f6b76;
  --blue: #093b70;
  --blue-2: #0e6fa8;
  --cyan: #38a8be;
  --orange: #ee8f49;
  --paper: #ffffff;
  --wash: #f3f7fa;
  --line: #dfe7ed;
  --shadow: 0 20px 60px rgba(9, 59, 112, .1);
  --serif: Georgia, "Times New Roman", serif;
  --sans: "Trebuchet MS", Inter, Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 78px; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; }
.shell { width: min(1180px, calc(100% - 48px)); margin-inline: auto; }
.skip-link { position: fixed; top: -60px; left: 16px; z-index: 100; padding: 10px 16px; color: white; background: var(--blue); }
.skip-link:focus { top: 10px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid rgba(223, 231, 237, .85);
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(14px);
}
.nav { height: 72px; display: flex; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--blue); font-weight: 800; letter-spacing: .08em; text-decoration: none; }
.brand-mark { display: grid; place-items: center; width: 32px; height: 32px; border: 2px solid var(--blue); font-family: var(--serif); font-style: italic; font-size: 21px; line-height: 1; }
.nav-links { display: flex; align-items: center; gap: 30px; }
.nav-links a { color: #52606d; font-size: 14px; text-decoration: none; transition: color .2s; }
.nav-links a:hover { color: var(--blue); }
.nav-toggle { display: none; width: 38px; height: 38px; padding: 8px; border: 0; background: transparent; }
.nav-toggle span { display: block; height: 2px; margin: 5px 0; background: var(--blue); transition: transform .2s, opacity .2s; }

.hero { padding: 92px 0 76px; text-align: center; }
.eyebrow { display: flex; align-items: center; justify-content: center; gap: 10px; margin-bottom: 24px; color: var(--blue-2); font-size: 13px; font-weight: 700; letter-spacing: .14em; text-transform: uppercase; }
.eyebrow span { width: 30px; height: 2px; background: var(--cyan); }
.hero h1 { max-width: 1000px; margin: 0 auto; font-family: var(--serif); font-size: clamp(42px, 6.4vw, 78px); font-weight: 500; line-height: 1.06; letter-spacing: -.035em; }
.hero h1 span { color: var(--blue); font-style: italic; }
.tagline { margin: 20px 0 28px; color: var(--muted); font-family: var(--serif); font-size: 22px; font-style: italic; }
.authors { display: flex; flex-wrap: wrap; justify-content: center; gap: 5px 20px; max-width: 980px; margin: 0 auto; font-size: 16px; }
.authors a { color: var(--blue-2); text-underline-offset: 3px; }
sup { font-size: .65em; }
.affiliations { display: flex; flex-wrap: wrap; justify-content: center; gap: 2px 20px; margin: 12px auto 0; color: var(--muted); font-size: 13px; }
.author-note { margin: 5px 0 22px; color: #7b8791; font-size: 12px; }
.hero-actions { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; padding: 9px 18px; border: 1px solid var(--blue); color: var(--blue); background: white; font-size: 14px; font-weight: 700; text-decoration: none; transition: transform .2s, box-shadow .2s, background .2s; }
.button.primary { color: white; background: var(--blue); }
a.button:hover { transform: translateY(-2px); box-shadow: 0 8px 22px rgba(9,59,112,.18); }
.button.disabled { border-color: #ccd5dc; color: #89949d; cursor: default; }
.hero-visual { position: relative; margin-top: 58px; padding: 18px 18px 14px; border: 1px solid var(--line); background: white; box-shadow: var(--shadow); }
.hero-visual::before { content: "KEY RESULT"; position: absolute; top: -14px; left: 24px; padding: 5px 12px; color: white; background: var(--blue); font-size: 11px; font-weight: 800; letter-spacing: .12em; }
.hero-visual img { width: 100%; }
.hero-visual p { max-width: 820px; margin: 12px auto 0; color: var(--muted); font-size: 13px; }

.metrics-band { color: white; background: var(--blue); }
.metrics { display: grid; grid-template-columns: repeat(4, 1fr); }
.metrics article { position: relative; padding: 38px 30px 34px; border-left: 1px solid rgba(255,255,255,.16); }
.metrics article:last-child { border-right: 1px solid rgba(255,255,255,.16); }
.metrics strong { display: block; font-family: var(--serif); font-size: clamp(30px, 4vw, 48px); font-weight: 400; line-height: 1; }
.metrics span { display: block; margin-top: 8px; font-weight: 700; }
.metrics small { display: block; margin-top: 3px; color: #b9d3e4; font-size: 12px; }

.section { padding: 110px 0; }
.section-heading { max-width: 820px; margin-bottom: 50px; }
.section-heading > span, .mini-label { color: var(--blue-2); font-size: 12px; font-weight: 800; letter-spacing: .14em; text-transform: uppercase; }
.section-heading h2 { margin: 8px 0 0; font-family: var(--serif); font-size: clamp(36px, 5vw, 58px); font-weight: 500; line-height: 1.1; letter-spacing: -.025em; }
.section-heading p { max-width: 700px; margin: 18px 0 0; color: var(--muted); }
.overview-grid { display: grid; grid-template-columns: 1.45fr .8fr; gap: 70px; align-items: start; }
.abstract h3 { margin-top: 0; color: var(--blue); font-size: 15px; letter-spacing: .12em; text-transform: uppercase; }
.abstract p { color: #44515c; font-family: var(--serif); font-size: 19px; line-height: 1.75; }
.question-card { position: relative; margin-top: 8px; padding: 40px 34px 34px; border-top: 4px solid var(--cyan); background: var(--wash); }
.question-number { position: absolute; top: -27px; right: 24px; color: rgba(9,59,112,.09); font-family: var(--serif); font-size: 130px; line-height: 1; }
.question-card h3 { position: relative; margin-top: 0; font-family: var(--serif); font-size: 27px; font-weight: 500; line-height: 1.25; }
.question-card p { position: relative; color: var(--muted); }
.triplet { position: relative; display: flex; align-items: center; justify-content: space-between; gap: 5px; margin-top: 28px; color: var(--blue); font-size: 12px; font-weight: 800; }
.triplet span { padding: 5px 8px; border: 1px solid #a9c9db; background: white; }
.triplet i { color: var(--cyan); font-style: normal; }

.method-section { background: var(--wash); }
.method-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.method-card { position: relative; min-height: 390px; padding: 34px 30px 28px; overflow: hidden; border: 1px solid var(--line); background: white; }
.method-card::after { content: ""; position: absolute; right: -45px; bottom: -65px; width: 170px; height: 170px; border: 26px solid rgba(56,168,190,.08); border-radius: 50%; }
.method-index { color: #94a0a9; font-size: 12px; font-weight: 800; letter-spacing: .1em; }
.method-icon { display: grid; place-items: center; width: 56px; height: 56px; margin: 42px 0 24px; color: white; background: var(--blue-2); font-family: var(--serif); font-size: 30px; font-style: italic; }
.ric .method-icon { background: var(--orange); }
.dic .method-icon { background: var(--blue); }
.method-card h3 { margin: 0; font-family: var(--serif); font-size: 25px; font-weight: 500; line-height: 1.25; }
.method-card p { color: var(--muted); font-size: 14px; }
.formula { position: relative; z-index: 1; margin-top: 20px; padding-top: 16px; border-top: 1px solid var(--line); font-family: var(--serif); font-size: 13px; font-style: italic; }
.formula span { color: var(--blue); font-weight: 700; font-style: normal; }
.selection-flow { display: grid; grid-template-columns: .75fr 1.25fr; gap: 60px; align-items: center; margin-top: 22px; padding: 52px; color: white; background: var(--blue); }
.flow-copy h3 { margin: 6px 0 10px; font-family: var(--serif); font-size: 32px; font-weight: 500; }
.flow-copy p { margin: 0; color: #c5d9e8; font-size: 14px; }
.selection-flow .mini-label { color: #71c7d7; }
.flow-diagram { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.flow-node { min-width: 112px; padding: 16px 10px; border: 1px solid rgba(255,255,255,.35); text-align: center; font-size: 11px; }
.flow-node strong { font-size: 14px; }
.flow-stack { display: grid; grid-template-columns: 1fr 1fr; gap: 4px; min-width: 85px; }
.flow-stack span { padding: 5px; background: rgba(255,255,255,.13); text-align: center; font-size: 11px; }
.flow-stack strong { grid-column: 1 / -1; padding: 6px; color: var(--blue); background: #71c7d7; text-align: center; }
.flow-arrow { color: #71c7d7; font-size: 23px; }

.result-feature { display: grid; grid-template-columns: 1.65fr .75fr; gap: 44px; align-items: center; }
.result-feature img { border: 1px solid var(--line); box-shadow: var(--shadow); }
.result-copy { padding-right: 10px; }
.result-copy h3, .scale-card h3 { margin: 8px 0 14px; font-family: var(--serif); font-size: 30px; font-weight: 500; line-height: 1.22; }
.result-copy p, .scale-card p { color: var(--muted); }
.result-copy ul { margin: 24px 0 0; padding: 0; border-top: 1px solid var(--line); list-style: none; }
.result-copy li { display: flex; justify-content: space-between; padding: 9px 0; border-bottom: 1px solid var(--line); }
.result-copy li strong { color: var(--blue); }
.scale-card { display: grid; grid-template-columns: .8fr 1.2fr; gap: 70px; align-items: center; margin-top: 70px; padding: 50px; background: var(--wash); }
.scale-bars > div { display: grid; grid-template-columns: 110px 1fr 50px; gap: 10px; align-items: center; margin: 13px 0; font-size: 12px; }
.scale-bars i { position: relative; display: block; height: 13px; background: #dce6ec; }
.scale-bars i::after { content: ""; position: absolute; inset: 0 auto 0 0; width: var(--value); background: #70a9cb; }
.scale-bars b { color: var(--blue); text-align: right; }
.scale-bars .best i::after { background: var(--blue); }
.scale-bars .best { font-weight: 800; }

.contributions { color: white; background: #122c43; }
.contributions .section-heading > span { color: #71c7d7; }
.takeaway-grid { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid rgba(255,255,255,.2); }
.takeaway-grid article { padding: 36px 36px 20px 0; }
.takeaway-grid article + article { padding-left: 36px; border-left: 1px solid rgba(255,255,255,.2); }
.takeaway-grid b { color: #71c7d7; font-size: 13px; }
.takeaway-grid h3 { margin: 18px 0 8px; font-family: var(--serif); font-size: 27px; font-weight: 500; }
.takeaway-grid p { margin: 0; color: #b9c9d4; font-size: 14px; }

.citation-section { padding-bottom: 90px; }
.citation-box { position: relative; padding: 26px 28px; overflow-x: auto; border: 1px solid var(--line); background: var(--wash); }
.citation-box pre { margin: 0; font-size: 13px; line-height: 1.7; white-space: pre-wrap; }
.copy-button { position: absolute; top: 16px; right: 16px; padding: 7px 11px; border: 1px solid var(--blue); color: var(--blue); background: white; font: 700 11px var(--sans); cursor: pointer; }
.citation-note { color: #7d8891; font-size: 12px; }
footer { border-top: 1px solid var(--line); background: var(--wash); }
.footer-inner { display: flex; align-items: center; justify-content: space-between; padding-top: 42px; padding-bottom: 42px; }
.footer-inner div { display: flex; flex-direction: column; }
.footer-inner strong { color: var(--blue); font-size: 18px; letter-spacing: .08em; }
.footer-inner span, .footer-inner p { color: var(--muted); font-size: 12px; }
.footer-inner a { color: var(--blue); }

.reveal { opacity: 0; transform: translateY(18px); transition: opacity .65s ease, transform .65s ease; }
.reveal.visible { opacity: 1; transform: none; }

@media (max-width: 900px) {
  .metrics { grid-template-columns: repeat(2, 1fr); }
  .metrics article:nth-child(3) { border-top: 1px solid rgba(255,255,255,.16); }
  .metrics article:nth-child(4) { border-top: 1px solid rgba(255,255,255,.16); }
  .overview-grid, .result-feature, .scale-card, .selection-flow { grid-template-columns: 1fr; }
  .method-cards { grid-template-columns: 1fr; }
  .method-card { min-height: auto; }
  .method-icon { margin-top: 24px; }
  .takeaway-grid { grid-template-columns: 1fr; }
  .takeaway-grid article + article { padding-left: 0; border-left: 0; border-top: 1px solid rgba(255,255,255,.2); }
}

@media (max-width: 680px) {
  .shell { width: min(100% - 30px, 1180px); }
  .nav { height: 62px; }
  .nav-toggle { display: block; cursor: pointer; }
  .nav-links { position: absolute; top: 62px; left: 0; right: 0; display: none; align-items: stretch; gap: 0; padding: 10px 15px 18px; border-bottom: 1px solid var(--line); background: white; box-shadow: 0 15px 30px rgba(23,35,47,.08); }
  .nav-links.open { display: flex; flex-direction: column; }
  .nav-links a { padding: 10px; }
  .nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav-toggle.active span:nth-child(2) { opacity: 0; }
  .nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
  .hero { padding: 62px 0 52px; }
  .hero h1 { font-size: 42px; }
  .hero-visual { margin-top: 42px; padding: 8px; }
  .hero-visual p { padding: 0 8px; }
  .metrics { grid-template-columns: 1fr 1fr; }
  .metrics article { padding: 24px 15px; }
  .metrics strong { font-size: 30px; }
  .metrics span { font-size: 13px; }
  .section { padding: 76px 0; }
  .section-heading { margin-bottom: 35px; }
  .overview-grid { gap: 34px; }
  .abstract p { font-size: 17px; }
  .method-card { padding: 26px 22px; }
  .selection-flow { gap: 32px; padding: 30px 20px; }
  .flow-diagram { flex-wrap: wrap; justify-content: center; }
  .flow-arrow { transform: rotate(90deg); }
  .result-feature { gap: 28px; }
  .scale-card { gap: 25px; margin-top: 45px; padding: 30px 20px; }
  .scale-bars > div { grid-template-columns: 90px 1fr 45px; }
  .footer-inner { align-items: flex-start; flex-direction: column; gap: 14px; }
  .copy-button { position: static; margin-top: 18px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
}