:root{--ink:#153b43;--deep:#124b55;--aqua:#69b6ae;--sand:#e9d8b4;--paper:#f4f8f5;--line:#d2e1df;--muted:#607b7d}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:15px/1.65 Arial,sans-serif}header{height:74px;padding:0 max(6vw,22px);display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);background:#fff}.brand{font:700 20px Georgia;text-decoration:none;color:var(--ink)}.icon{color:var(--aqua);font-size:28px;vertical-align:-3px;margin-right:5px}nav{display:flex;gap:28px;font-size:13px}nav a{color:inherit;text-decoration:none}.badge,.kicker{font-size:10px;letter-spacing:.16em;color:#43847e;font-weight:bold}.hero{padding:68px max(10vw,24px) 52px;display:grid;grid-template-columns:1fr 1fr;gap:7vw;align-items:center;background:#e7f0ed}.hero h1{font:600 clamp(51px,6vw,75px)/1 Georgia;letter-spacing:-2.5px;margin:17px 0}.hero h1 em{font-weight:400;color:#42857e}.hero-copy p:not(.kicker){max-width:420px;color:#536d70}.button{display:inline-flex;gap:23px;padding:13px 17px;background:var(--deep);color:white;text-decoration:none;font-weight:bold;margin-top:8px}.aquarium{height:240px;border:5px solid #93b7b1;border-top:9px solid #567c78;background:linear-gradient(#cce9e6 0 70%,#94c5bd 70%);position:relative;box-shadow:0 15px 0 #c5d7d1,0 22px 0 #d9e4dc;border-radius:3px 3px 11px 11px;overflow:hidden}.waterline{position:absolute;top:34%;height:1px;background:#fff8;left:0;right:0}.fish{position:absolute;color:#e7a65d;font-size:26px}.f1{top:32%;left:25%}.f2{top:52%;right:18%;color:#df8765}.plant{position:absolute;bottom:20px;color:#3f8f70;font:95px Georgia}.one{left:17%}.two{left:65%;font-size:72px}.gravel{height:21px;bottom:0;position:absolute;left:0;right:0;background:radial-gradient(ellipse at center,#c9b17e 0 25%,transparent 30%) 0 0/20px 18px,#c6b083}.aquarium>span{position:absolute;bottom:-1px;right:9px;font-size:8px;color:#365b59;background:#fff9;padding:2px 5px}.ad{height:88px;max-width:970px;margin:0 auto 36px;border:1px dashed #c9d8d5;display:flex;flex-direction:column;align-items:center;justify-content:center;color:#839896;font-size:12px}.ad small{font-size:9px;letter-spacing:.18em}.tools{padding:41px max(10vw,24px)}.section-title{display:flex;justify-content:space-between;align-items:end;margin-bottom:20px}.section-title h2,.notes h2{font:600 35px/1.1 Georgia;letter-spacing:-1.3px;margin:7px 0}.section-title>p{font-size:12px;color:var(--muted)}.tool-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:16px}.tank-form{background:#fff;border:1px solid var(--line);padding:22px;display:grid;grid-template-columns:1fr 1fr;gap:14px;align-content:start}.tank-form label{display:grid;gap:7px;font-size:11px;color:#597175}.tank-form label small{font-size:9px;color:#869394}.tank-form input,.tank-form select{height:41px;width:100%;border:1px solid var(--line);padding:0 9px;background:#fff;color:var(--ink);font:14px Arial}.tank-form button{grid-column:span 2;margin-top:4px;border:0;cursor:pointer}.results{background:var(--deep);padding:22px;color:#fff}.results .kicker{color:#aed5ce}.results h3{font:600 29px Georgia;margin:10px 0 16px}.resultline{display:flex;justify-content:space-between;padding:11px 0;border-top:1px solid #ffffff33;font-size:13px}.resultline strong{color:#d5eab8}.results small{display:block;color:#bfdbd5;font-size:10px;line-height:1.6;margin-top:15px}.safety{margin-top:14px;background:#f3ebd8;border-left:3px solid #c29244;padding:13px 16px;display:flex;gap:13px;font-size:11px;color:#5f5d4b}.safety b{min-width:120px;color:#705827}.notes{padding:42px max(10vw,24px);background:#e2eeeb;display:grid;grid-template-columns:.9fr 1.1fr;gap:8vw}.notes>div:last-child{font-size:13px;color:#526d6c}.notes>div:last-child p{margin-top:0}.ad:last-of-type{margin-bottom:42px}footer{border-top:1px solid var(--line);padding:20px max(6vw,22px);display:flex;justify-content:space-between;font-size:11px;color:#74888a}@media(max-width:720px){.badge{display:none}nav{gap:13px;font-size:11px}.hero{grid-template-columns:1fr;padding-top:42px;gap:28px}.aquarium{height:200px}.section-title{display:block}.section-title>p{max-width:360px}.tool-grid{grid-template-columns:1fr}.tank-form{padding:17px;gap:11px}.notes{grid-template-columns:1fr;gap:0;padding:32px 24px}.ad{margin-left:14px;margin-right:14px}footer{flex-direction:column;gap:8px}.safety{display:block}.safety b{display:block;margin-bottom:5px}}

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