:root{color-scheme:light;--ink:#193744;--gold:#986622;--line:#c8d4da}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:#f0f3f4;color:var(--ink);font:18px/1.6 Arial,sans-serif}.brand,main,footer{max-width:1050px;margin:auto}.brand{display:flex;align-items:center;gap:22px;padding:30px 32px;border-bottom:2px solid var(--ink);font-size:16px;letter-spacing:.09em}.brand img{width:56px;height:56px}.brand small{font-size:11px;letter-spacing:.17em}main{padding:35px 32px}h1,h2,h3{line-height:1.2}h1{font-size:clamp(34px,5vw,55px);letter-spacing:-.03em;margin:12px 0}.intro{font-size:22px;color:#466270;max-width:700px}.eyebrow{font-size:12px;font-weight:bold;letter-spacing:.12em;color:var(--gold)}.actions,.topic-index{display:flex;flex-wrap:wrap;gap:10px;margin:28px 0}.actions a,.activity,.topic-index a{display:inline-flex;align-items:center;min-height:46px;border:1px solid var(--line);padding:10px 15px;border-radius:6px;text-decoration:none;color:var(--ink);background:white;font-size:15px;font-weight:bold}.activity{background:var(--ink);color:white}.reference{background:#e5edf0;padding:22px 28px;border-left:4px solid var(--gold);border-radius:4px}.reference p{font-size:16px}.topic{scroll-margin-top:15px;margin-top:55px}.topic h2{font-size:28px;border-bottom:2px solid var(--ink);padding-bottom:18px}.problem{background:#fff;border:1px solid var(--line);border-radius:9px;padding:25px 32px;margin:24px 0;scroll-margin-top:20px}.problem h3{font-size:25px;margin:10px 0 18px}.brief{max-width:800px}.figure{width:100%;height:auto}.figure.single{max-width:530px}figure{margin:22px 0;background:#fff}table{border-collapse:collapse;font-size:16px;margin:12px 0}td,th{border:1px solid var(--line);padding:6px 16px;text-align:right}caption{font-weight:bold;text-align:left}summary{min-height:44px;cursor:pointer;padding:10px 0;font-size:16px}.worked{background:#f1f5f6;border-left:3px solid var(--gold);padding:12px 20px}.worked p{margin:8px 0}.find{font-weight:bold}footer{border-top:1px solid var(--ink);padding:20px 32px;font-size:12px;letter-spacing:.05em}a:focus-visible,summary:focus-visible{outline:3px solid #c68c2d;outline-offset:3px}@media(max-width:600px){.brand{padding:20px 18px;font-size:12px;gap:14px}.brand img{width:43px;height:43px}main{padding:22px 16px}.problem{padding:18px}.reference{padding:18px}.topic h2{font-size:23px}.problem h3{font-size:22px}.actions a{width:100%}}@media print{body{background:white;font-size:10pt}.actions,.activity,.topic-index{display:none}main{padding:0}.problem{break-inside:avoid;border:0;border-top:1px solid #888;padding:12px 0}.brand{padding:0 0 10px}.topic{break-before:page}.reference{background:white}footer{font-size:8pt}}