:root{--navy:#073b66;--blue:#0a6fae;--blue2:#1386c5;--light:#eaf3f9;--ink:#17212b;--muted:#5c6b78;--line:#d7e2ea;--paper:#f5f7f9;--good:#1f7a47;--warn:#9a6500;--bad:#a83232;--purple:#62479a;--softgood:#f1faf5;--softwarn:#fff8e8;--softbad:#fff4f4;--softpurple:#f6f3fc}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Arial,Helvetica,sans-serif;color:var(--ink);background:var(--paper);line-height:1.5}header{background:linear-gradient(100deg,var(--navy),var(--blue));color:#fff;padding:28px 22px 22px}.wrap{max-width:1180px;margin:auto}.eyebrow{font-size:12px;letter-spacing:.09em;text-transform:uppercase;opacity:.86;margin-bottom:8px;font-weight:700}h1{font-size:34px;line-height:1.08;margin:0 0 8px}.subtitle{margin:0;max-width:900px;font-size:16px;opacity:.94}.coursebar{max-width:1180px;margin:18px auto 0;display:flex;gap:6px;flex-wrap:wrap}.coursebar .step{background:rgba(255,255,255,.14);padding:8px 10px;border-radius:5px;font-size:12px;text-align:center}.coursebar .step.active{background:#fff;color:var(--navy);font-weight:700}.coursebar .step.done{background:rgba(255,255,255,.28)}.syncbar{max-width:1180px;margin:14px auto 0;padding:0 18px}.syncbox{background:#fff;border:1px solid var(--line);border-radius:9px;padding:11px 14px;display:flex;gap:9px;align-items:center;flex-wrap:wrap}.syncbox b{color:var(--navy)}.syncmsg{font-size:13px;color:var(--muted)}.layout{max-width:1180px;margin:18px auto 60px;display:grid;grid-template-columns:255px minmax(0,1fr);gap:24px;padding:0 18px}aside{position:sticky;top:16px;height:max-content;background:#fff;border:1px solid var(--line);border-radius:9px;padding:14px}aside .title{font-weight:700;color:var(--navy);margin-bottom:8px}aside a{display:block;text-decoration:none;color:#334654;border-left:3px solid transparent;padding:8px 9px;font-size:14px}aside 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var(--line);border-radius:6px;padding:10px;background:#fbfcfd}.stepno{width:28px;height:28px;border-radius:50%;background:var(--navy);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:700}.keys{display:flex;align-items:center;gap:6px;flex-wrap:wrap;margin:9px 0}.key{border:1px solid #a8b2bb;background:#fff;border-radius:5px;padding:5px 9px;font-size:12px;font-weight:700;box-shadow:0 1px 1px rgba(0,0,0,.08)}.arrow{color:var(--muted);font-weight:700}table{width:100%;border-collapse:collapse;margin:12px 0;font-size:14px}th,td{border:1px solid var(--line);padding:10px 11px;text-align:left;vertical-align:top}th{background:#e8f1f7;color:var(--navy)}ul{margin:8px 0;padding-left:21px}li{margin:5px 0}.small{font-size:13px;color:var(--muted)}.quizq{border-top:1px solid var(--line);padding:17px 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0;font-size:12px;color:var(--muted)}@media(max-width:900px){.layout{grid-template-columns:1fr}aside{position:relative;top:0}.goalgrid,.symbols{grid-template-columns:1fr}.coursebar{padding:0 16px}}@media(max-width:560px){h1{font-size:28px}.formula{font-size:27px}.stepbox{grid-template-columns:1fr}.stepno{margin-bottom:2px}}