RGB order matters

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</style></head><body><main><header><p class="kicker">COLOR PRACTICE · FOUR CANONICAL TUPLES</p><h1>RGB order matters</h1><p>Target RGB(64,128,192). Three distinct wrong choices allowed. Numeric Practice is a different task from hidden-tuple visual practice.</p></header><div class="actions"><button type="button" id="visual">Visual practice</button><button type="button" id="numeric">Numeric Practice</button><button type="button" id="reset">Reset this mode</button></div><section class="panel"><h2>Choose one option</h2><div class="two"><button type="button" id="c1" style="text-align:left"><span style="display:block;background:rgb(64,128,192);height:80px;border:1px solid #202d3b;border-radius:6px;margin-bottom:12px" aria-hidden="true"></span>Option 1 · C1<span id="tuple0" style="display:block" hidden></span></button><button type="button" id="c2" style="text-align:left"><span style="display:block;background:rgb(192,128,64);height:80px;border:1px solid #202d3b;border-radius:6px;margin-bottom:12px" aria-hidden="true"></span>Option 2 · C2<span id="tuple1" style="display:block" hidden></span></button><button type="button" id="c3" style="text-align:left"><span style="display:block;background:rgb(64,192,128);height:80px;border:1px solid #202d3b;border-radius:6px;margin-bottom:12px" aria-hidden="true"></span>Option 3 · C3<span id="tuple2" style="display:block" hidden></span></button><button type="button" id="c4" style="text-align:left"><span style="display:block;background:rgb(128,64,192);height:80px;border:1px solid #202d3b;border-radius:6px;margin-bottom:12px" aria-hidden="true"></span>Option 4 · C4<span id="tuple3" style="display:block" hidden></span></button></div><div id="state" class="result" role="status" aria-live="polite"></div><div id="feedback" class="result" role="status" aria-live="polite">Choose an option.</div></section><section class="panel"><h2>Guess history</h2><div id="history" class="result" role="status" aria-live="polite">No guesses yet.</div><div id="explanations" class="strip" hidden></div></section><footer>Compare RGB channels in order. A repeated rejected option does not consume another wrong choice.</footer><noscript>JavaScript is required for the local controls. The accompanying article contains worked examples.</noscript></main><script>
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const target=[64,128,192],options=[[64,128,192],[192,128,64],[64,192,128],[128,64,192]],rejected=new Set(),history=[];let mode='visual',phase='Playing',remaining=3;function render(){$('state').textContent=phase+' / Mode: '+mode+' / Remaining distinct wrong choices: '+remaining;options.forEach((x,i)=>{$('tuple'+i).hidden=mode==='visual'&&phase==='Playing';$('tuple'+i).textContent='RGB('+x.join(', ')+')'+(rejected.has(i)?' · rejected':'');$('c'+(i+1)).setAttribute('aria-disabled',String(rejected.has(i)||phase!=='Playing'));});$('history').textContent=history.length?history.join(' / '):'No guesses yet.';$('explanations').hidden=phase==='Playing';$('explanations').textContent='C1 exactly matches all channels. C2 exchanges red/blue. C3 exchanges green/blue. C4 exchanges red/green.';}function reset(m){mode=m;phase='Playing';remaining=3;rejected.clear();history.length=0;$('feedback').textContent='Choose an option.';render();}options.forEach((rgb,i)=>$('c'+(i+1)).addEventListener('click',()=>{if(phase!=='Playing')return;if(rejected.has(i)){$('feedback').textContent='C'+(i+1)+' already rejected; budget unchanged.';return;}if(rgb.every((v,j)=>v===target[j])){phase='Won';history.push('C'+(i+1)+' correct; Won, remaining '+remaining);$('feedback').textContent='Exact RGB match. Won without a wrong-choice penalty.';}else{rejected.add(i);remaining--;history.push('C'+(i+1)+' wrong; remaining '+remaining);if(remaining===0)phase='Lost';$('feedback').textContent=phase==='Lost'?'Lost: three distinct wrong choices. Reset for a new round.':'Wrong channel order; C'+(i+1)+' rejected once.';}render();}));$('visual').addEventListener('click',()=>reset('visual'));$('numeric').addEventListener('click',()=>reset('numeric'));$('reset').addEventListener('click',()=>reset(mode));render();
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