:root{font:16px/1.5 system-ui,sans-serif;color:#182b40;background:#f6f7f9}*{box-sizing:border-box}body{margin:0}header{height:64px;background:white;border-bottom:1px solid #dce1e7;display:flex;align-items:center;justify-content:space-between;padding:0 32px}header span,aside p,.source,small{color:#647080;font-size:13px}main{max-width:1400px;margin:auto;display:grid;grid-template-columns:224px minmax(0,1fr);gap:32px;padding:32px}aside{align-self:start}h2{font-size:12px;text-transform:uppercase;letter-spacing:.08em}nav{display:grid;gap:4px}button{font:inherit;cursor:pointer;border:1px solid #ccd3dc;background:white;color:#182b40;border-radius:6px;padding:10px 14px;min-height:44px}button:hover:not(:disabled){background:#eaf0f6;border-color:#73879c}button:active:not(:disabled){background:#dce6f0}button:focus-visible,summary:focus-visible{outline:3px solid #4676a2;outline-offset:3px}button:disabled{opacity:.5;cursor:default}.primary{background:#182f49;color:white;border-color:#182f49}.primary:hover:not(:disabled){background:#294966}nav button{text-align:left;border-color:transparent;background:transparent}nav button.selected{background:#e5ebf2;border-color:#bdc9d5;font-weight:650}.heading{display:flex;justify-content:space-between;gap:24px}h1{font-size:28px;line-height:1.2;margin:4px 0 8px}#view{margin:0;color:#647080}.timer{text-align:right;min-width:110px}.timer small{display:block}.timer strong{font-size:30px;font-variant-numeric:tabular-nums}.toolbar{display:flex;align-items:center;gap:8px;margin:24px 0 16px}#progress{margin-left:auto;font-size:14px;color:#647080}.plate{border:1px solid #dce1e7;background:white;border-radius:8px;overflow:hidden;height:560px}#diagram{display:block;width:100%;height:100%}.question{display:flex;justify-content:space-between;gap:16px;margin:20px 0 12px}#feedback{font-size:14px}#answers{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}#answers button{text-align:left}#answers button.correct{border:2px solid #182f49;background:#e5ebf2;opacity:1}#answers button.wrong{text-decoration:line-through}#next{margin-top:16px;min-width:180px}details{margin-top:24px;border-top:1px solid #dce1e7;padding-top:16px}summary{cursor:pointer}#coverage{columns:2;font-size:14px;padding-left:24px}.source{margin-top:24px}dialog{border:1px solid #ccd3dc;border-radius:8px;padding:32px;max-width:480px}dialog::backdrop{background:#182b4066}[hidden]{display:none!important}@media(max-width:800px){main{display:block;padding:16px}aside{margin-bottom:24px}nav{display:flex;overflow:auto}nav button{white-space:nowrap}aside p{display:none}.plate{height:430px}#answers{grid-template-columns:1fr 1fr}header{padding:0 16px}header span{display:none}.toolbar{flex-wrap:wrap}#progress{width:100%;margin:8px 0 0}.question{display:block}#feedback{display:block}}@media(max-width:430px){h1{font-size:24px}#answers{grid-template-columns:1fr}.plate{height:390px}#coverage{columns:1}}
:root .label-dot{display:inline-block;width:12px;height:12px;border-radius:50%;flex-shrink:0;box-shadow:0 0 0 2px white,0 0 0 3px #cbd2db}#answers button{display:flex;align-items:center;gap:12px}#answers .selected-label{outline:2px solid #182f49;outline-offset:1px;background:#e5ebf2}.target{cursor:pointer}.target[aria-disabled=true]{cursor:default}.target:hover circle,.target:focus circle{stroke:#172c43;stroke-width:3}.target:focus{outline:none}.target.solved{opacity:.55}.view-button{font-size:13px;margin:4px 4px 4px 0}.view-button.selected{background:#e5ebf2;border-color:#637b92}#diagram{min-height:390px}.plate{height:620px}
.plate{height:auto;overflow:visible}#diagram{height:auto;aspect-ratio:1.12;min-height:600px;max-height:none}.dot-target{width:100%;height:100%;min-height:0;padding:0;border:3px solid currentColor;border-radius:50%;font-size:30px;font-weight:700;background:white;display:grid;place-items:center}.dot-target:hover:not(:disabled){background:#eef3f8}.dot-target:focus-visible{outline:5px solid #182b40;outline-offset:3px}@media(max-width:800px){.plate{overflow:auto}#diagram{min-width:850px;min-height:760px}.plate:before{content:'Full plate — scroll sideways to inspect the dots.';display:block;padding:8px 12px;font-size:12px;color:#647080}}
.exercise{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(270px,.9fr);gap:24px;align-items:start}.plate{overflow:hidden;height:auto}.plate:before{display:none!important}#diagram{width:100%;height:auto;min-width:0;min-height:0;aspect-ratio:1104/1424;display:block}.landmark-hit{border:0;padding:0;min-height:0;width:100%;height:100%;background:transparent!important;border-radius:50%}.landmark-hit:focus-visible{outline:4px solid #234e78}.answer-panel{position:sticky;top:24px}.answer-panel #answers{grid-template-columns:1fr 1fr;gap:8px}.answer-panel #answers button{font-size:14px;min-height:44px;padding:8px 12px}.question{display:block;margin:0 0 20px}.question strong{font-size:17px}.question #feedback{display:block;min-height:24px;margin-top:8px;color:#52647a}.answer-actions{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}.answer-actions #next{margin:0;min-width:0}.instructions{font-size:13px;color:#647080;border-top:1px solid #dce1e7;margin-top:24px;padding-top:16px}.instructions p{display:block}.heading #view{font-size:14px}main{max-width:1600px;grid-template-columns:190px minmax(0,1fr);gap:24px;padding:24px}nav button span{color:#647080;margin-right:8px}.timer strong{font-size:28px}@media(max-width:1100px){.exercise{grid-template-columns:minmax(0,1fr) 290px}.answer-panel #answers{grid-template-columns:1fr}}@media(max-width:800px){main{display:block;padding:16px}.exercise{grid-template-columns:1fr}.answer-panel{position:static}.answer-panel #answers{grid-template-columns:1fr 1fr}.instructions{display:none}.plate{max-width:600px;margin:auto;width:100%}}@media print{header,aside,.toolbar,.answer-actions{display:none}main{display:block}.answer-panel{position:static}.exercise{grid-template-columns:1fr 1fr}button{color:black!important;background:white!important}}
#answers button.correct{color:#23734d;border-color:#86b493;background:#f0f7f2;text-decoration:line-through;text-decoration-thickness:2px;text-decoration-color:#23734d;opacity:1}
#answers button.correct:hover:not(:disabled){background:#e7f3eb;border-color:#5e9b70}
#answers button:disabled.correct{opacity:1;cursor:default}
#feedback.correct{color:#23734d;font-weight:650}
#hint{margin:8px 0 14px;color:#52647a;font-size:13px;min-height:20px}
#hintButton{min-width:110px}
@media(max-width:800px){header{height:56px}main{padding:12px;gap:16px}.heading{align-items:flex-start}.heading h1{font-size:24px}.timer strong{font-size:24px}.toolbar{margin:16px 0 12px}.plate{height:auto;max-height:none}.answer-panel{padding-bottom:24px}.answer-panel #answers{grid-template-columns:1fr;gap:6px}.answer-panel #answers button{min-height:48px}.answer-actions{position:sticky;bottom:0;background:#f6f7f9;padding:10px 0;z-index:3}.answer-actions button{flex:1}.exercise{gap:16px}nav{padding-bottom:4px}nav button{min-height:42px}}
@media(max-width:430px){header{padding:0 12px}main{padding:10px}.plate{border-radius:6px}.question strong{font-size:16px}#progress{font-size:12px}.toolbar button{padding:9px 10px}.answer-actions{gap:6px}.answer-actions button{font-size:14px}}
.legal{max-width:760px;display:block;background:white;border:1px solid #dce1e7;border-radius:8px;padding:32px}.legal h1{margin-top:0}.legal h2{margin-top:28px;text-transform:none;letter-spacing:0;font-size:19px}.legal a,header a{color:#234e78}@media(max-width:600px){.legal{padding:20px}}
.site-footer{max-width:1400px;margin:24px auto;padding:0 32px 24px;display:flex;gap:18px;color:#647080;font-size:13px}.site-footer a{color:#234e78}@media(max-width:600px){.site-footer{padding:0 12px 20px;flex-wrap:wrap}}
.seo-intro{max-width:780px;margin:0 0 18px;color:#52647a;font-size:14px}