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#d0d9c4;margin-top:22px;padding-top:16px;font-size:10px}.topic b span{float:right}.lesson{display:grid;grid-template-columns:.8fr 1.2fr;gap:70px;padding:90px 0 25px;align-items:center}.lessonintro h2{font-size:39px}.lessonintro>p:not(.eyebrow){color:var(--muted);line-height:1.8;font-size:14px}.rule{border-left:3px solid #94ae5b;padding:5px 18px;margin-top:28px}.rule>span{font-size:10px;font-weight:700;letter-spacing:1px}.rule p{font-size:13px;line-height:1.7}.rule>div{font-size:20px;font-weight:700}.lab{background:white;border:1px solid var(--line);border-radius:18px;padding:25px 30px;box-shadow:0 10px 40px #17352806}.labhead{display:flex;justify-content:space-between;align-items:center}.lab .pill{background:#f1f5e7;padding:7px 10px;border-radius:5px;font-size:9px}.textbutton{border:0;background:none;color:var(--muted);font-size:12px}.models{display:flex;align-items:center;justify-content:center;gap:12px;margin:20px 0 28px}figure{margin:0;width:44%;text-align:center}figure svg{width:100%;max-width:180px;display:block;margin:auto}figcaption{font-size:28px;font-weight:700;margin:10px 0 5px}figure small{color:var(--muted);font-size:10px}.equal{font-size:27px}.sliderlabel{display:flex;justify-content:space-between;font-size:12px;font-weight:600}output{color:#71883f}input[type=range]{width:100%;margin:18px 0 6px;accent-color:#6c893b;cursor:pointer}.rangeends{display:flex;justify-content:space-between;color:var(--muted);font-size:10px}.presets{display:flex;justify-content:center;gap:8px;margin:15px}.presets button{background:white;color:var(--ink);border:1px solid var(--line);border-radius:6px;padding:7px 16px;font-size:12px}.presets button.selected{background:var(--ink);color:white}.insight{background:#f0f6e4;border-radius:9px;padding:14px;display:flex;flex-direction:column;text-align:center;gap:7px}.insight strong{font-size:21px}.insight span{font-size:11px}.fine{font-size:10px;line-height:1.6;color:var(--muted);margin:14px 0 0}.notice{background:#f0eaf7;border:1px solid #e7ddf0;border-radius:10px;padding:14px 24px;display:flex;gap:18px;align-items:center;margin:15px 0 75px}.notice>span{font-size:30px;color:#8d6aa9}.notice p{font-size:12px;line-height:1.8}.challengebadge{font-size:10px;font-weight:700;border:1px solid var(--line);padding:12px;border-radius:20px}.quiz{max-width:850px;margin:0 auto;background:white;border:1px solid var(--line);border-radius:16px;padding:30px 40px}.quiztop{display:flex;justify-content:space-between;font-size:12px;font-weight:700}.progress{height:5px;background:#edf0e6;border-radius:10px;margin:16px 0 30px;overflow:hidden}#progressfill{height:100%;background:#8aa847;transition:width .3s}.questiontag{font-size:11px;color:var(--muted)}.quiz h3{font-size:26px;line-height:1.4;margin:14px 0 24px}.answers{display:grid;grid-template-columns:1fr 1fr;gap:12px}.answer{border:1px solid var(--line);padding:17px;text-align:left;background:#fafbf7;color:var(--ink);border-radius:9px;font-size:18px}.answer:hover:not(:disabled){background:#edf3de;border-color:#8ea55c}.answer.correct{background:#e3f1d1;border-color:#6d933b}.answer.wrong{background:#fbe9df;border-color:#ce7952}.answer:disabled{cursor:default;color:var(--ink)}.quizactions{display:flex;justify-content:space-between;align-items:center;margin-top:22px;gap:16px}.hintbtn{border:0;background:none;color:var(--muted);font-size:12px;padding:10px}.next{background:var(--ink);color:white;border:0;border-radius:8px;padding:13px 20px;font-size:13px}.feedback,.hint{padding:15px;border-radius:8px;font-size:13px;line-height:1.7;margin-top:18px}.hint{background:#fff6db}.feedback{background:#f0f5e7}.results{text-align:center;padding:25px 0}.results .bigscore{font-size:65px;font-weight:800;color:#789443}.results p{line-height:1.8;color:var(--muted)}.endnote{text-align:center;margin:75px 0 65px}.endnote>span{font-size:10px;letter-spacing:1.5px;color:var(--muted)}.endnote h2{margin:15px 0 20px;font-size:26px}.endnote a{font-size:12px;border-bottom:1px solid var(--ink);padding-bottom:4px}footer{max-width:1280px;margin:auto;border-top:1px solid var(--line);padding:27px 38px;display:flex;justify-content:space-between;gap:20px;align-items:center}footer .brand{font-size:16px}footer>span{font-size:10px;color:var(--muted)}@media(min-width:1400px){main{max-width:1160px}}@media(max-width:1250px){main{margin:0 38px}.hero{gap:35px}h1{font-size:57px}.decorcircle{width:130px}.lesson{gap:35px}.topic .pill{font-size:6px;right:7px}}@media(max-width:800px){header{padding:20px 22px;flex-wrap:wrap}nav{order:3;width:100%;gap:20px;justify-content:space-between;font-size:12px}.brand{font-size:18px}main{margin:0 22px}.hero{grid-template-columns:1fr;padding:45px 0;gap:35px}h1{font-size:52px}.heroart{max-width:500px;width:96%;margin:auto}.decorcircle{width:150px}.topics{grid-template-columns:1fr 1fr}.sectiontitle{align-items:flex-start;flex-direction:column}.sectiontitle>.muted{display:none}h2{font-size:27px}.lesson{grid-template-columns:1fr;padding-top:55px;gap:25px}.lessonintro h2{font-size:33px}.rule{margin-top:20px}.notice{margin-bottom:45px;padding:12px 16px}.quiz{padding:24px 20px}.quiz h3{font-size:23px}.endnote{margin:50px 0}footer{padding:25px 22px;flex-wrap:wrap}footer>span:last-child{display:none}}@media(max-width:420px){.heroart{padding:25px 18px}.decorcircle{width:115px}.topics{gap:10px}.topic{padding:18px 13px}.topic .pill{position:static;display:inline-block;font-size:6px}.topicicon{height:49px}.topic h3{font-size:19px}.lab{padding:20px 14px}.models{gap:5px}.presets button{padding:8px 13px}.answers{gap:8px}.answer{padding:14px;font-size:16px}.quizactions{gap:6px}.next{padding:12px}.eyebrow{font-size:9px}h1{font-size:46px}.intro{font-size:15px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}
/* Topic links can wrap as the learning library grows. */
@media(max-width:800px){header nav{flex-wrap:wrap;row-gap:12px}}

/* Explicit text and contrasting feedback: colour is never the only signal. */
.feedback-wrong,.feedback-dec.feedback-wrong,.feedback.feedback-wrong,.measure-result.feedback-wrong{background:#fff0e9;color:#842f20;border:2px solid #b3543d}
.feedback-correct,.feedback-dec.feedback-correct,.feedback.feedback-correct,.measure-result.feedback-correct{background:#e7f2da;color:#2f561e;border:2px solid #64883c}

.controls button.feedback-wrong{background:#fff0e9;color:#842f20;border:2px solid #b3543d}
.controls button.feedback-correct{background:#e7f2da;color:#2f561e;border:2px solid #64883c}

.subject-horizon{display:flex;flex-wrap:wrap;gap:12px 24px;padding:24px 0;border-top:1px solid #ddd;border-bottom:1px solid #ddd;font-size:14px}.subject-horizon strong{width:100%}.subject-horizon span{color:#555}