:root {
  --ink: #315874;
  --ink-soft: #547790;
  --teal: #168d9c;
  --teal-light: #c9edf0;
  --blue: #dcecf6;
  --sky: #f2faff;
  --paper: #ffffff;
  --line: #c9dfea;
  --orange: #ee8765;
  --orange-light: #fff0e9;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--sky); color: var(--ink); font-family: system-ui, -apple-system, "Segoe UI", sans-serif; line-height: 1.62; }
a { color: #167d98; text-decoration: underline; text-underline-offset: 3px; }
a:hover { color: #dc6b48; }
a:focus-visible, summary:focus-visible { outline: 3px solid var(--orange); outline-offset: 4px; border-radius: 4px; }
h1, h2, h3, p { margin-top: 0; }
h1 { font-size: 40px; line-height: 1.15; letter-spacing: -0.04em; font-weight: 760; }
h2 { font-size: 28px; line-height: 1.2; letter-spacing: -0.025em; font-weight: 730; }
h3 { font-size: 20px; line-height: 1.3; letter-spacing: -0.012em; }
p { font-size: 16px; line-height: 1.7; }
ul { padding-left: 22px; }
.shell { width: min(1230px, calc(100% - 64px)); margin-inline: auto; }
.eyebrow { display: inline-block; color: var(--teal); font-size: 12px; font-weight: 750; letter-spacing: .15em; text-transform: uppercase; margin-bottom: 14px; }

.site-header { background: rgba(242,250,255,.98); border-bottom: 1px solid var(--line); }
.header-line { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 25px; }
.mark { display: flex; align-items: center; gap: 12px; color: var(--ink); text-decoration: none; font-size: 21px; line-height: 1; font-weight: 800; letter-spacing: .04em; white-space: nowrap; }
.mark small { display: block; margin-top: 7px; font-size: 10px; letter-spacing: .13em; font-weight: 750; color: var(--teal); }
.mark-symbol { position: relative; width: 41px; height: 41px; flex: none; border-radius: 12px; background: var(--teal-light); border: 2px solid var(--teal); }
.mark-symbol::before { content: ""; position: absolute; inset: 11px 8px 6px; border-radius: 50%; border: 3px solid var(--teal); }
.mark-symbol::after { content: ""; position: absolute; width: 5px; height: 5px; top: 4px; right: 7px; border-radius: 50%; background: var(--orange); }
.desktop-navigation { display: flex; gap: 23px; flex-wrap: wrap; align-items: center; }
.desktop-navigation a { text-decoration: none; font-size: 14px; font-weight: 650; color: var(--ink-soft); }
.desktop-navigation a:hover, .desktop-navigation a[aria-current] { color: var(--teal); }
.mobile-navigation { display: none; }

.hero { display: grid; grid-template-columns: 1.07fr .93fr; gap: 38px; align-items: center; padding-top: 56px; padding-bottom: 46px; }
.hero-copy { max-width: 620px; }
.hero-copy h1 { max-width: 610px; margin-bottom: 23px; }
.hero-copy p { margin-bottom: 17px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.primary-action, .secondary-action { display: inline-block; text-decoration: none; border-radius: 9px; padding: 11px 19px; font-size: 14px; font-weight: 650; }
.primary-action { background: var(--teal); color: white; }
.primary-action:hover { background: #187e8d; color: white; }
.secondary-action { border: 1px solid #94bdcf; color: var(--ink); background: white; }
.secondary-action:hover { color: var(--teal); background: var(--teal-light); }
.hero-media { display: grid; grid-template-columns: .88fr 1.12fr; gap: 17px; align-items: center; border-radius: 25px; background: linear-gradient(140deg,#d6f0f5 0%,#e7f5fa 100%); padding: 25px 20px; border: 1px solid #b7dae7; }
.washer-illustration { width: 100%; min-width: 0; display: flex; align-items: center; justify-content: center; }
.washer-face { height: 260px; width: min(200px,100%); background: #ffffff; border: 2px solid #95c7d7; border-radius: 17px 17px 12px 12px; box-shadow: 0 13px 0 #a2ccd9, 0 23px 22px rgba(80,138,170,.13); position: relative; }
.washer-face::before { content: ""; position: absolute; top: 60px; left: 0; right: 0; border-bottom: 2px solid #c0e0e9; }
.washer-display { position: absolute; top: 19px; left: 19px; height: 22px; width: 78px; background: #d6f1ef; border: 1px solid #6cb6bc; border-radius: 4px; display: flex; align-items: center; gap: 6px; padding: 5px 8px; }
.washer-display i { display: block; height: 3px; width: 14px; background: var(--teal); }
.wash-knob { position: absolute; top: 18px; right: 19px; width: 26px; height: 26px; background: #ebf8fa; border: 4px solid #8fbacb; border-radius: 50%; }
.washer-door { position: absolute; width: 72%; aspect-ratio: 1; border-radius: 50%; left: 14%; top: 79px; border: 10px solid #a6cfdd; background: #f5fcff; box-shadow: inset 0 0 0 4px #d2e5ee; overflow: hidden; }
.washer-door::before { content: ""; position: absolute; inset: 13px; border: 2px dashed #7db4c5; border-radius: 50%; }
.washer-water { position: absolute; inset: 56% 0 0; background: #90d3df; border-radius: 46% 45% 0 0; }
.washer-water span { position: absolute; width: 8px; height: 8px; border: 2px solid white; border-radius: 50%; top: 17px; left: 22%; }
.washer-water span:nth-child(2) { width: 13px; height: 13px; top: 22px; left: 63%; }
.washer-water span:nth-child(3) { width: 5px; height: 5px; top: 8px; left: 78%; }
.washer-foot { position: absolute; bottom: -15px; width: 18px; height: 7px; background: #8fb3c2; border-radius: 1px 1px 5px 5px; }
.foot-left { left: 15px; }.foot-right { right: 15px; }
.media-facts { min-width: 0; }
.fact-small { display: block; color: var(--teal); font-size: 11px; font-weight: 780; letter-spacing: .12em; margin-bottom: 4px; }
.media-facts strong { font-size: clamp(28px,3vw,40px); line-height: 1.1; color: var(--ink); display: block; letter-spacing: -.04em; }
.media-facts strong small { font-size: 13px; font-weight: 640; letter-spacing: 0; }
.media-facts p { font-size: 16px; line-height: 1.52; margin-top: 8px; margin-bottom: 19px; }

.feature-ledger { background: var(--paper); border: 1px solid var(--line); border-radius: 17px; overflow: hidden; margin-bottom: 62px; }
.ledger-head { display: flex; align-items: center; gap: 25px; background: var(--ink); color: white; padding: 17px 26px; }
.ledger-head span { font-size: 12px; font-weight: 750; letter-spacing: .13em; color: #a6e4eb; white-space: nowrap; }
.ledger-head h2 { color: white; margin: 0; font-size: 28px; }
.ledger-items { display: grid; grid-template-columns: repeat(3,1fr); }
.ledger-items article { padding: 20px 26px; border-right: 1px solid var(--line); }
.ledger-items article:last-child { border-right: 0; }
.ledger-items strong { display: block; font-size: 27px; line-height: 1.25; color: var(--teal); letter-spacing: -.025em; }
.ledger-items span { display: block; font-size: 14px; margin-top: 9px; line-height: 1.5; }
.ledger-note { padding: 18px 26px 22px; margin: 0; background: #e9f7f9; border-top: 1px solid var(--line); }

.topic-section { margin-bottom: 64px; }
.section-title { margin-bottom: 24px; }
.section-title h2 { margin: 0; }
.section-title-split { display: grid; grid-template-columns: 1fr 1fr; align-items: end; gap: 34px; }
.section-title-split p { margin: 0; max-width: 520px; }
.topic-grid { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 16px; }
.topic-card { background: white; padding: 23px 24px 18px; border-radius: 12px; border: 1px solid var(--line); display: flex; flex-direction: column; }
.topic-card:nth-child(6n + 2), .topic-card:nth-child(6n + 5) { background: #e9f7fa; }
.card-index { font-size: 11px; letter-spacing: .13em; font-weight: 760; color: var(--teal); text-transform: uppercase; }
.topic-card h3 { margin: 14px 0 11px; }
.topic-card h3 a { color: #167d98; text-decoration: underline; }
.topic-card h3 a:hover { color: var(--teal); }
.topic-card p { margin-bottom: 10px; line-height: 1.55; }

.observations { margin-bottom: 55px; padding: 30px 34px 31px; border-radius: 17px; background: #dbf1f2; }
.observation-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 38px; }
.observation-grid p { margin-bottom: 0; }
.sources { margin-top: 55px; margin-bottom: 70px; padding-top: 22px; border-top: 1px solid var(--line); }
.sources h2 { margin-bottom: 16px; }
.sources ol { margin: 0; padding-left: 23px; }
.sources li { margin-bottom: 9px; padding-left: 5px; font-size: 14px; line-height: 1.6; }

.article-intro { display: grid; grid-template-columns: minmax(0,1.25fr) minmax(310px,.75fr); gap: 44px; align-items: stretch; margin-top: 48px; margin-bottom: 62px; }
.breadcrumbs { display: flex; align-items: center; gap: 11px; font-size: 13px; margin-bottom: 22px; color: var(--ink-soft); }
.article-heading h1 { margin-bottom: 22px; max-width: 750px; }
.article-heading p { max-width: 730px; margin-bottom: 15px; }
.article-facts { padding: 23px 25px; background: linear-gradient(160deg,#e0f2f7,#d5ecee); border-radius: 16px; border: 1px solid #abd4de; display: flex; flex-direction: column; }
.fact-top { display: flex; justify-content: space-between; color: var(--teal); font-size: 12px; font-weight: 750; letter-spacing: .1em; }
.pulse { display: block; width: 14px; height: 14px; border: 3px solid var(--orange); border-radius: 50%; }
.article-facts h2 { margin: 20px 0 15px; }
.article-facts p { margin-bottom: 17px; }
.article-facts ul { margin: auto 0 0; background: white; border-radius: 10px; padding: 15px 18px 15px 37px; border: 1px solid var(--line); }
.article-facts li { margin-bottom: 8px; }
.article-facts li:last-child { margin-bottom: 0; }

.chapter { margin-bottom: 60px; }
.chapter-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.prose-block { padding: 28px 30px 15px; background: white; border: 1px solid var(--line); border-radius: 14px; }
.prose-block.lighter { background: #e7f4f9; }
.prose-block p { margin-bottom: 14px; }
.exam-band { margin-bottom: 60px; padding: 39px 0 36px; background: #e0f1f5; border-block: 1px solid #c5e1e8; }
.steps { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 14px; }
.step { background: white; border-radius: 12px; padding: 22px 24px 17px; border: 1px solid #c5e1e8; }
.step-number { display: inline-grid; place-items: center; background: var(--teal-light); color: var(--teal); border-radius: 8px; height: 34px; width: 39px; font-weight: 760; }
.step h3 { margin: 15px 0 11px; }
.step p { margin: 0; }
.exam-note { margin: 18px 0 0; padding-left: 19px; border-left: 3px solid var(--teal); }
.compare-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 17px; }
.compare-item { position: relative; padding: 24px 28px 20px; border: 1px solid var(--line); border-radius: 13px; background: #edf7fb; }
.compare-item.second { background: #fff0e9; border-color: #efccbf; }
.compare-letter { display: inline-block; color: var(--teal); font-weight: 800; font-size: 13px; margin-bottom: 10px; }
.second .compare-letter { color: #c96e51; }
.compare-item h3 { margin-bottom: 12px; }
.compare-item p { margin-bottom: 0; }
.post-compare { margin: 19px 0 0; }
.post-compare + .post-compare { margin-top: 12px; }
.analysis-section { display: grid; grid-template-columns: 1.15fr .85fr; gap: 24px; align-items: stretch; margin-bottom: 60px; }
.analysis-note { background: #fff; border: 1px solid var(--line); padding: 26px 30px; border-radius: 14px; }
.analysis-note h2 { margin-bottom: 12px; }
.analysis-note p { margin-bottom: 0; }
.formula-box { border-radius: 14px; padding: 26px 30px; border: 1px solid #a7d7dc; background: #d4eff1; }
.formula-box span { display: block; font-size: 13px; font-weight: 700; color: var(--teal); text-transform: uppercase; letter-spacing: .08em; }
.formula-box strong { display: block; font-size: clamp(27px,3vw,38px); letter-spacing: -.04em; line-height: 1.22; margin-top: 12px; margin-bottom: 12px; }
.formula-box p { margin: 0; }
.related { margin-top: 35px; margin-bottom: 75px; }
.related-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 13px; }
.related-grid a { border-radius: 9px; border: 1px solid var(--line); background: #fff; padding: 18px 20px; color: #167d98; text-decoration: underline; font-size: 17px; font-weight: 650; }
.related-grid a:hover { background: var(--teal-light); color: var(--teal); }
.related-grid span { display: block; font-size: 11px; font-weight: 720; letter-spacing: .1em; margin-bottom: 7px; color: var(--teal); text-transform: uppercase; }
.context-link { color: inherit; text-decoration: none; font-weight: inherit; }
.context-link:hover { color: var(--teal); background: #daf3f3; }

.home-hero { padding-top: 58px; display: grid; grid-template-columns: 1.15fr .85fr; gap: 48px; margin-bottom: 60px; align-items: center; }
.home-hero h1 { max-width: 680px; }
.home-indicator { padding: 22px 28px 29px; background: #d8edf3; border: 1px solid #abd6df; border-radius: 19px; text-align: center; }
.home-indicator>span { font-size: 12px; letter-spacing: .16em; color: var(--teal); font-weight: 750; }
.home-indicator strong { display: block; font-size: 20px; margin: 10px 0; }
.home-indicator p { margin: 0; }
.radial { width: 165px; height: 165px; margin: 20px auto; border: 22px solid #9ed4dc; border-top-color: var(--teal); border-right-color: var(--orange); border-radius: 50%; display: grid; place-items: center; background: white; }
.radial b { font-size: 40px; color: var(--teal); }
.home-phases { margin-bottom: 62px; }
.phase-grid { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 17px; }
.phase-grid article { background: #fff; border-radius: 13px; border: 1px solid var(--line); padding: 24px 26px; display: flex; flex-direction: column; }
.phase-grid span { font-size: 12px; letter-spacing: .1em; color: var(--teal); font-weight: 760; }
.phase-grid h3 { margin: 15px 0 10px; }
.phase-grid p { margin-bottom: 14px; }
.phase-grid a { margin-top: auto; font-size: 14px; }

.site-footer { background: #dceef4; border-top: 1px solid var(--line); padding: 31px 0; }
.footer-grid { display: flex; align-items: center; justify-content: space-between; gap: 35px; }
.footer-name { font-weight: 800; font-size: 17px; }
.footer-grid p { margin: 6px 0 0; }
.footer-grid nav { display: flex; flex-wrap: wrap; align-items: center; gap: 18px; }
.footer-grid nav a { font-size: 14px; }

@media (max-width: 1120px) {
  .shell { width: min(100% - 40px, 1230px); }
  .header-line { gap: 12px; }
  .desktop-navigation { gap: 13px; }
  .desktop-navigation a { font-size: 13px; }
  .hero { gap: 22px; }
  .hero-media { grid-template-columns: 1fr; gap: 20px; }
  .washer-face { height: 207px; width: 165px; }
  .washer-door { top: 68px; }
  .media-facts { display: grid; grid-template-columns: 1fr; }
  .media-facts p { margin-bottom: 15px; }
  .article-intro { grid-template-columns: 1.15fr .85fr; gap: 25px; }
}

@media (max-width: 810px) {
  .desktop-navigation { display: none; }
  .mobile-navigation { display: block; position: relative; }
  .mobile-navigation summary { cursor: pointer; padding: 9px 14px; border: 1px solid #8cbbc8; background: white; border-radius: 8px; font-weight: 680; }
  .mobile-navigation nav { position: absolute; right: 0; top: calc(100% + 8px); z-index: 5; width: min(260px, calc(100vw - 40px)); background: white; border: 1px solid var(--line); border-radius: 12px; box-shadow: 0 13px 20px #b7d6e277; display: grid; padding: 10px; }
  .mobile-navigation nav a { padding: 8px 10px; }
  .hero, .article-intro, .home-hero { grid-template-columns: 1fr; }
  .hero { padding-top: 36px; }
  .hero-media { grid-template-columns: .8fr 1.2fr; }
  .washer-face { height: 230px; width: 180px; }
  .washer-door { top: 78px; }
  .article-intro { margin-top: 33px; margin-bottom: 45px; }
  .section-title-split { grid-template-columns: 1fr; gap: 8px; }
  .topic-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .article-facts ul { margin-top: 10px; }
  .footer-grid { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 620px) {
  .shell { width: calc(100% - 30px); }
  h1 { font-size: 40px; overflow-wrap: anywhere; }
  h2 { font-size: 28px; overflow-wrap: anywhere; }
  p { font-size: 16px; }
  .hero, .home-hero { padding-top: 30px; }
  .hero-media { grid-template-columns: 1fr; padding: 24px; }
  .media-facts { display: block; }
  .media-facts p:last-child { margin-bottom: 0; }
  .feature-ledger { margin-bottom: 43px; }
  .ledger-head { align-items: flex-start; flex-direction: column; gap: 6px; padding: 17px; }
  .ledger-items { grid-template-columns: 1fr; }
  .ledger-items article { padding: 15px 19px; border-right: 0; border-bottom: 1px solid var(--line); }
  .ledger-note { padding: 17px 19px; }
  .topic-grid, .steps, .compare-grid, .chapter-pair, .phase-grid, .related-grid, .observation-grid, .analysis-section { grid-template-columns: 1fr; }
  .topic-section, .chapter, .exam-band, .home-phases { margin-bottom: 42px; }
  .topic-card { min-height: auto; }
  .observations { padding: 22px; margin-bottom: 35px; }
  .article-facts { padding: 20px; }
  .prose-block { padding: 20px; }
  .exam-band { padding: 28px 0; }
  .compare-item, .analysis-note, .formula-box { padding: 20px; }
  .related { margin-bottom: 47px; }
  .sources { margin: 35px auto 47px; }
  .site-footer { padding: 26px 0; }
}