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}


/* Version 2: a mathematics reference book and a coordinate instrument. */
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.brand{font:23px Georgia,serif;font-weight:400;letter-spacing:-.5px}.brand-symbol{display:none}.brand small{display:none}.topbar nav a{font-size:13px}.nav-pill{border:0;border-radius:0;padding:0}.topbar nav a:last-child{border-bottom:1px solid;padding-bottom:2px}
.footer{border-top:1px solid var(--ink);padding-top:25px;font-size:11px}.footer strong{font:17px Georgia,serif}.footer p{margin-top:7px}.footer nav{gap:22px}
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.notebook-paper{background:#fffdf8;border-left:1px solid var(--line);border-right:1px solid var(--line);padding:43px 45px 0;min-width:0}.paper-heading{display:grid;grid-template-columns:1fr 240px;align-items:end;gap:0 20px;padding-bottom:35px}.paper-heading .folio{grid-column:1/-1;margin:0 0 25px}.paper-heading h1{font:50px/.98 Georgia,serif;letter-spacing:-2px;margin:0}.paper-heading h1 em{font-weight:400;color:var(--accent)}.paper-heading>p:last-child{font:13px/1.8 Arial,sans-serif;color:var(--muted);margin:0 0 3px}
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/* Slope is an instrument, not another notebook. */
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/* V3 — playable mathematics, custom poster and plotting surface */
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