:root{--paper:#f7f5ed;--ink:#233f36;--green:#245e4c;--muted:#5d6e62;--line:#d8ddce;--lime:#e3efb4;--pink:#f2d6cd;--blue:#d7e6f1;--white:#fffef8;font-family:system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;color:var(--ink);background:var(--paper);font-synthesis:none}*{box-sizing:border-box}body{margin:0}header{max-width:1160px;margin:auto;padding:26px 30px 20px;display:flex;align-items:center;gap:18px}.brand{color:var(--ink);font-size:23px;font-weight:750;letter-spacing:-1px;text-decoration:none;white-space:nowrap}.brand-icon{font-size:36px;vertical-align:middle;color:var(--green);margin-right:8px}.year{margin-left:auto;font-size:10px;letter-spacing:1.6px;font-weight:700;color:var(--muted)}button,input{font:inherit}button,a,input{-webkit-tap-highlight-color:transparent}button{cursor:pointer;border:1px solid var(--line);border-radius:12px;background:var(--white);color:var(--ink);padding:13px 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var(--line);border-radius:12px;background:white;color:var(--ink)}.choice-buttons{display:flex;gap:12px;justify-content:center;flex-wrap:wrap}.choice-buttons button{min-width:140px}.feedback{padding:20px;text-align:left;background:#e7efdb;border-radius:14px;margin-top:22px;line-height:1.6;font-size:17px}.feedback.wrong{background:#f7e8db}.feedback p{font-size:17px;margin:6px 0 0}.next{margin-top:20px;width:100%}.results{text-align:center}.score{font:80px Georgia,serif;margin:20px}.review-list{text-align:left;display:grid;gap:12px;margin:25px 0}.review-item{padding:20px;background:var(--white);border:1px solid var(--line);border-radius:14px}.review-item p{font-size:16px;margin:6px 0}.review-item b{font-size:18px}.reference-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.reference-grid .card 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span{font-size:12px}.lesson{grid-template-columns:1fr;padding:23px}.lesson h2{font-size:34px}.learn-tabs button{flex:1;padding:10px 7px;font-size:14px}.question{padding:25px 18px}.choice-buttons button{min-width:0;flex:1;padding:12px 8px;font-size:15px}.big-number{font-size:60px}.game-top{gap:12px}footer{margin:20px;padding:20px 0}.visual{min-height:250px}h2{font-size:32px}}@media(prefers-reduced-motion:no-preference){.card:hover{transform:translateY(-3px);transition:transform .2s}.hero-art .number-tile{animation:arrive .7s ease-out}@keyframes arrive{from{opacity:0;translate:0 15px}to{opacity:1;translate:0 0}}}@media print{header,nav,footer,button,.source{display:none!important}body{background:white}main{padding:0}.reference-grid{display:block}.card{break-inside:avoid;margin-bottom:15px}.card .icon{display:none}h1{font-size:32px}}
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