:root{--bg: #e7e0cf;--card: #fbf7ee;--ink: #17160f;--muted: #6c6555;--accent: #fb4d1e;--yellow: #ffd83e;--shadow: 4px 4px 0 var(--ink);--r: 9px;--font-body: "Avenir Next", "Avenir", "Segoe UI", system-ui, -apple-system, Roboto, sans-serif;--font-head: "Futura", "Avenir Next Condensed", "Avenir Next", "Arial Black", system-ui, sans-serif}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:5rem}body{margin:0;font-family:var(--font-body);color:var(--ink);background:var(--bg);background-image:radial-gradient(#d8d0bb 1px,transparent 1px);background-size:26px 26px;line-height:1.55}.wrap{max-width:1080px;margin:0 auto;padding:0 1.25rem}h1,h2,h3{font-family:var(--font-head);line-height:1.12;margin:0 0 .6em}h2{font-size:clamp(1.6rem,3.5vw,2.3rem);text-align:center;margin-bottom:1.6em}p{margin:0 0 1em}mark{background:linear-gradient(transparent 8%,var(--yellow) 8%,var(--yellow) 88%,transparent 88%);color:inherit;padding:0 .12em}.btn{display:inline-block;padding:.7rem 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var(--ink);border-radius:var(--r);box-shadow:var(--shadow)}.face-front{background:var(--yellow);display:grid;place-items:center}.face-back{background:var(--card);transform:rotateY(180deg);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:.5rem;padding:1.4rem;text-align:center}.buffalo{width:clamp(180px,22vw,250px);height:auto;display:block}.quiz-label{font-family:var(--font-head);font-size:.75rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted)}.quiz-q{font-family:var(--font-head);font-size:clamp(1.05rem,1.8vw,1.3rem);font-weight:700;margin:0}.quiz-rule{width:3rem;border:none;border-top:2px dashed var(--muted);margin:.2rem 0}.quiz-a{font-family:var(--font-head);font-size:clamp(1.1rem,2vw,1.4rem);margin:0}.quiz-actions{display:flex;gap:.6rem;margin-top:.7rem}.pill{font-family:var(--font-head);font-size:.78rem;border:2px solid var(--ink);border-radius:999px;padding:.25rem .7rem;box-shadow:2px 2px 0 var(--ink);background:var(--card)}.pill-yes{background:var(--yellow)}.flip-hint{position:absolute;top:calc(100% + 1.2rem);left:50%;transform:translate(-50%);font-size:.85rem;color:var(--muted);white-space:nowrap}.chip{position:absolute;font-family:var(--font-head);font-size:.88rem;background:var(--card);border:2px solid var(--ink);border-radius:999px;padding:.35rem .8rem;box-shadow:3px 3px 0 var(--ink);white-space:nowrap;transition:opacity .35s ease}.hero-art:has(.flip-card.flipped) .chip{opacity:0}.chip-1{top:4%;left:2%;transform:rotate(-6deg)}.chip-2{bottom:10%;right:0;transform:rotate(4deg)}.chip-3{bottom:2%;left:0;transform:rotate(-3deg)}.features,.steps{padding:clamp(2.5rem,7vw,4.5rem) 0}.feature-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:1.4rem}.card{background:var(--card);border:2px solid var(--ink);border-radius:var(--r);box-shadow:var(--shadow);padding:1.4rem 1.5rem}.card h3{font-size:1.15rem;margin:.4em 0}.card 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var(--ink)}.mc-question{font-family:var(--font-head);font-size:1.05rem;font-weight:700;margin:0 0 1rem}.dot-grid{display:grid;grid-template-columns:repeat(7,1.15rem);gap:.35rem;margin-top:1rem}.dot{width:1.15rem;height:1.15rem;background:var(--yellow);border:2px solid var(--ink);border-radius:5px}.panel-readout{font-family:var(--font-head);font-weight:700;margin:1rem 0 0}.levels-note{text-align:center;color:var(--muted);max-width:34rem;margin:1.8em auto 0;font-size:.95rem}.fraction-bar{display:grid;grid-template-columns:repeat(8,1fr);gap:.45rem;margin-top:1.3rem}.frac-seg{height:3.4rem;background:var(--bg);border:2px solid var(--ink);border-radius:6px;box-shadow:2px 2px 0 var(--ink);cursor:pointer;transition:background .12s ease}.frac-seg.on{background:var(--yellow)}.sine-svg{display:block;width:100%;height:auto;margin-top:.4rem;color:var(--ink)}.sine-label{display:flex;align-items:center;gap:.8rem;font-family:var(--font-head);font-weight:700}.sine-label 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var(--ink);border-radius:var(--r);box-shadow:var(--shadow)}.faq-item summary{list-style:none;cursor:pointer;font-family:var(--font-head);font-size:1.08rem;font-weight:700;padding:1.1rem 3rem 1.1rem 1.4rem;position:relative}.faq-item summary::-webkit-details-marker{display:none}.faq-item summary:after{content:"+";position:absolute;right:1.3rem;top:50%;transform:translateY(-50%);font-size:1.5rem}.faq-item[open] summary:after{content:"−"}.faq-item p{margin:0;padding:0 1.4rem 1.3rem;color:var(--muted)}.cta{padding:clamp(2.5rem,7vw,4.5rem) 0 clamp(3.5rem,8vw,5.5rem)}.cta-box{background:var(--yellow);border:2px solid var(--ink);border-radius:var(--r);box-shadow:6px 6px 0 var(--ink);padding:clamp(2rem,6vw,3.5rem);text-align:center}.cta-box h2{margin-bottom:.4em}.cta-box p{margin-bottom:1.6em;color:var(--ink)}.site-footer{background:var(--card);border-top:2px solid var(--ink);padding:1.2rem 0;font-size:.92rem}.footer-inner{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:.5rem}.site-footer a{color:var(--ink)}@media(max-width:480px){.chip-1{top:-6%;left:0}.chip-2{bottom:-8%;right:0}.chip-3{bottom:-8%;left:0}.flip-hint{top:calc(100% + 2.8rem)}}@media(max-width:820px){.hero-grid{grid-template-columns:1fr;gap:3.5rem;text-align:center}.lead{margin-inline:auto}.hero-actions{justify-content:center}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.btn,.flip-inner{transition:none}}