:root{--navy:#102f3c;--ink:#203c48;--muted:#60737e;--blue:#176b8a;--orange:#efb45d;--line:#dbe3e8;--paper:#f5f8fa}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:Arial,Helvetica,sans-serif;font-size:16px;line-height:1.65}button,input{font:inherit}button,a,input,summary{outline-offset:4px}button{cursor:pointer}button:disabled{cursor:default;opacity:.5}header{min-height:96px;background:var(--navy);color:white;display:flex;align-items:center;gap:35px;padding:20px 4%}.brand{display:flex;align-items:center;gap:12px;color:white;text-decoration:none;font-weight:700;font-size:21px;line-height:1.3}.brand small{display:block;letter-spacing:2px;font-size:12px;color:#afd0da;margin-top:5px}.brand-icon{display:grid;place-items:center;width:42px;height:46px;border:2px solid var(--orange);color:var(--orange);font-family:Georgia,serif;font-size:32px}nav{display:flex;gap:5px;margin-left:auto}nav button{background:none;color:#c4d5db;border:0;padding:13px 14px;border-radius:6px;font-size:14px;font-weight:bold}nav button.active{background:#284957;color:white}.header-tag{font-size:12px;letter-spacing:1px;border-left:1px solid #496571;padding-left:24px;color:var(--orange)}.intro{padding:33px 4%;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);background:white}.eyebrow{font-size:12px;letter-spacing:1.5px;font-weight:bold;color:var(--blue)}.intro h2{font-family:Georgia,serif;font-size:30px;line-height:1.2;margin:8px 0}.intro p{margin:0;color:var(--muted)}.progress{text-align:right;font-size:14px;font-weight:bold}.progress small{display:block;font-weight:normal;color:var(--muted);margin-top:4px}.workspace{display:grid;grid-template-columns:275px minmax(0,1fr) 215px;max-width:1500px;margin:auto;gap:38px;padding:35px 4% 70px}.curriculum{min-width:0}.group-title{font-weight:bold;font-size:15px;margin:24px 0 9px;display:flex;align-items:center;gap:9px}.level{font-size:12px;border:1px solid #beced8;border-radius:4px;padding:0 6px;color:var(--muted)}.lesson-link{width:100%;text-align:left;border:0;background:none;display:flex;align-items:flex-start;gap:10px;padding:9px 10px;font-size:14px;line-height:1.45;color:#526b78;border-left:3px solid transparent;border-radius:0 5px 5px 0}.lesson-link:hover{background:#e8eff3}.lesson-link.selected{background:#dfedf3;color:#125d79;border-left-color:var(--blue);font-weight:bold}.lesson-number{font-size:12px;min-width:20px;margin-top:2px;color:#6c8794}.lesson{background:white;border:1px solid var(--line);border-radius:10px;padding:32px;align-self:start;min-width:0;box-shadow:0 5px 16px #1d415005}.lesson-top{display:flex;justify-content:space-between;align-items:center;gap:10px;font-size:12px;color:var(--muted)}.pill{display:inline-block;font-size:12px;font-weight:bold;letter-spacing:.4px;border-radius:4px;padding:4px 10px;background:#e4f0f5;color:var(--blue)}h1{font-family:Georgia,serif;font-size:38px;line-height:1.15;margin:26px 0 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#bbcbd4;border-radius:5px}.input-pair{display:flex;gap:15px}.result{padding:20px;background:var(--navy);color:white;border-radius:6px}.result span{display:block;font-size:14px;color:#c0d5dd}.result strong{font-size:40px;display:block;line-height:1.4}.result small{font-size:18px}.calculator p{font-size:14px;color:var(--muted);margin-bottom:0}.case li{margin-bottom:12px}.case ol{padding-left:20px}.case details{margin:25px 0}.case summary{cursor:pointer;font-weight:bold;color:var(--blue)}.checklist{margin-top:25px}.checklist label{display:flex;gap:12px;margin:14px 0}.checklist input{width:18px;accent-color:var(--blue)}footer{border-top:1px solid var(--line);display:flex;justify-content:space-between;gap:15px;padding:25px 4%;font-size:12px;color:var(--muted);background:white}@media(min-width:1450px){.workspace{gap:45px}.lesson{padding:40px}}@media(max-width:1150px){.workspace{grid-template-columns:245px minmax(0,1fr);gap:24px}.tip,.header-tag{display:none}header{gap:15px}}@media(max-width:760px){header{flex-wrap:wrap;padding:18px 20px}nav{margin:8px 0 0;width:100%;overflow:auto}nav button{white-space:nowrap;padding:10px;font-size:14px}.intro{padding:25px 20px;display:block}.intro h2{font-size:27px}.progress{text-align:left;margin-top:18px}.workspace{display:flex;flex-direction:column;padding:24px 16px}.curriculum{max-height:260px;overflow:auto;border:1px solid var(--line);padding:15px;border-radius:7px}.lesson{padding:24px 20px}.lesson-top{flex-wrap:wrap}h1{font-size:32px}.lead{font-size:17px}.lesson-footer{flex-wrap:wrap}.term-grid,.resource-grid,.practice-grid{grid-template-columns:1fr}.page{padding:0 18px}.input-pair{gap:10px}.input-pair label{min-width:0}footer{flex-direction:column}.intro .eyebrow{font-size:11px}}

.welcome-banner{background:#efb45d;color:#102f3c;text-align:center;padding:42px 20px;border-bottom:4px solid #102f3c}.welcome-banner h2{font-family:Georgia,serif;font-size:clamp(2.25rem,6vw,5rem);line-height:1.15;margin:0;font-weight:bold;overflow-wrap:anywhere}