:root{--navy:#052b40;--navy-2:#0b405a;--water:#39a9c4;--foam:#eef9f7;--paper:#fffdf8;--sun:#ffcc4d;--ink:#092f40;--muted:#55727c;--line:#c9dde0;--radius:24px;--shadow:0 24px 64px #052b4021}*{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth;scroll-padding-top:100px}body{min-height:100vh;color:var(--ink);background:var(--paper);-webkit-font-smoothing:antialiased;font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;font-size:17px;line-height:1.66}a{color:inherit;text-underline-offset:4px;text-decoration-thickness:1.5px}:focus-visible{outline-offset:3px;outline:3px solid #c47a00}::selection{background:var(--sun);color:var(--navy)}h1,h2,h3{letter-spacing:-.045em;text-wrap:balance;line-height:1.05}h1{font-size:clamp(3.2rem,7.6vw,7.3rem);font-weight:820}h2{font-size:clamp(2.1rem,4.5vw,4rem);font-weight:780}h3{font-size:1.4rem}p{text-wrap:pretty}.shell{width:min(1180px,100% - 48px);margin-inline:auto}.reading-width{width:min(840px,100% - 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#5c9fb8}.loop-tank{border:8px solid var(--navy);background:#f8fbf8;border-radius:72px 72px 30px 30px;width:175px;height:248px;position:absolute;bottom:45px;right:52px;overflow:hidden}.water-line{background:linear-gradient(#5dc8d8,#1e98ba);height:68%;position:absolute;bottom:0;left:0;right:0}.heater-coil{z-index:2;border:7px solid var(--sun);border-top:0;border-radius:0 0 50% 50%;width:90px;height:50px;position:absolute;bottom:58px;right:35px}.loop-tank span{z-index:3;text-align:center;text-transform:uppercase;width:100%;font-size:.7rem;font-weight:850;line-height:1.2;position:absolute;top:32px}.loop-wire{background:var(--sun);height:4px;position:absolute}.wire-a{width:120px;top:142px;right:180px;transform:rotate(-20deg)}.wire-b{width:105px;top:293px;right:205px;transform:rotate(25deg)}.answer-section{background:#fff;padding-block:95px}.answer-section h2{margin-bottom:27px}.answer-box{border-left:5px solid var(--water);background:#e5f6f4;border-radius:0 17px 17px 0;padding:27px 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h2{max-width:700px;font-size:clamp(2.1rem,4vw,3.5rem)}.article{padding-bottom:100px}.article-hero{padding-top:98px;padding-bottom:68px}.article-hero h1{font-size:clamp(3.05rem,7vw,6.25rem)}.dek{color:var(--muted);margin-top:26px;font-size:1.27rem;line-height:1.58}.article-body>section{border-top:1px solid var(--line);padding-block:43px}.article-body h2{margin-bottom:24px;font-size:clamp(1.9rem,4vw,3rem)}.steps{counter-reset:steps;gap:12px;list-style:none;display:grid}.steps li{background:var(--foam);border:1px solid var(--line);counter-increment:steps;border-radius:16px;padding:22px 22px 22px 72px;position:relative}.steps li:before{content:counter(steps);width:34px;height:34px;color:var(--navy);background:var(--sun);border-radius:50%;place-items:center;font-size:.75rem;font-weight:850;display:grid;position:absolute;top:20px;left:20px}.steps p{color:var(--muted);margin-top:5px}.notice,.source-panel{background:var(--foam);border:1px solid 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