Study Break Unit Converter
Build a unit converter for a study break scenario: includes real content, actionable controls, clear status feedback, and responsive layouts.
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<header class="mast"><div><span class="eyebrow">industrial / unit converter / INTERMEDIATE</span><h1>Study Break Unit Converter</h1><p class="intro">Build a unit converter for a study break scenario: includes real content, actionable controls, clear status feedback, and responsive layouts.</p></div><span class="scenario">Study Break</span></header>
<div class="composition-split"><aside class="split-note"><b>CASE 02</b><span>Master the semantic structure, responsive composition, keyboard interaction, and state synchronization of the unit converter.</span></aside><section class="demo" aria-label="Study Break Unit Converter interaction area"><div class="workflow-session"><header class="session-command"><div><span class="eyebrow">Study Break SESSION</span><h2>Study Break Timer Console</h2></div><output id="workflowSessionClock">00:45</output><label>Round Duration<input id="workflowSessionLength" type="range" min="15" max="90" step="15" value="45"><span>sec</span></label><button id="workflowSessionToggle" class="action primary" type="button">Start Break</button></header><div id="workflowSessionProgress" role="progressbar" aria-label="Study Break Timer Progress" aria-valuemin="0" aria-valuemax="100" aria-valuenow="0"><i></i></div><section id="workflowCore" class="workflow-core session-stage" data-session-phase="ready" tabindex="-1"><!-- 11DZ_CORE_START:mini-apps-games-unit-converter --><div class="mini converter"><span class="eyebrow">UNIT CONVERTER</span><h2>Unit Converter</h2><label><span>kilometers</span><input id="unitInput" type="number" min="0" step="0.1" value="5" data-core-bridge="mini-apps-games-unit-converter"></label><button id="swapUnit" class="action" type="button">Kilometers → Miles</button><output id="unitOutput" class="metric">3.11 Miles</output></div><!-- 11DZ_CORE_END --></section><footer class="session-log"><strong id="workflowSessionScore">0 interaction checkpoints</strong><ol id="workflowSessionLaps" aria-label="Round Log"></ol></footer></div><p id="status" class="status" role="status" aria-live="polite"></p></section></div>
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<script>
'use strict';
const statusOutput = document.querySelector('#status');
const announce = message => { statusOutput.textContent = message; };
/* 11DZ_CORE_SCRIPT_START:mini-apps-games-unit-converter */
let direction='km';const input=document.querySelector('#unitInput');const output=document.querySelector('#unitOutput');const swap=document.querySelector('#swapUnit');function convert(){const value=Number(input.value)||0;const result=direction==='km'?value*.621371:value/0.621371;output.textContent=result.toFixed(2)+(direction==='km'?' mile':' kilometers');announce('Conversion Result '+output.textContent);}input.addEventListener('input',convert);swap.addEventListener('click',()=>{direction=direction==='km'?'mile':'km';swap.textContent=direction==='km'?'Kilometers → Miles':'Miles → Kilometers';convert();});convert();
/* 11DZ_CORE_SCRIPT_END */
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const workflowSessionCore=document.querySelector('#workflowCore');const workflowSessionToggle=document.querySelector('#workflowSessionToggle');const workflowSessionLength=document.querySelector('#workflowSessionLength');const workflowSessionState={phase:'ready',elapsed:0,limit:Number(workflowSessionLength.value),checkpoints:[],timer:null};function workflowSessionFormat(seconds){return String(Math.floor(seconds/60)).padStart(2,'0')+':'+String(seconds%60).padStart(2,'0');}function workflowSessionDrive(){const percent=Math.min(100,Math.round(workflowSessionState.elapsed/workflowSessionState.limit*100));document.querySelector('#workflowSessionClock').textContent=workflowSessionFormat(Math.max(0,workflowSessionState.limit-workflowSessionState.elapsed));const progress=document.querySelector('#workflowSessionProgress');progress.setAttribute('aria-valuenow',String(percent));progress.querySelector('i').style.width=percent+'%';workflowSessionCore.dataset.sessionPhase=workflowSessionState.phase;document.querySelector('#workflowSessionScore').textContent=workflowSessionState.checkpoints.length+' interactive checkpoints';}function workflowSessionLap(label){workflowSessionState.checkpoints.push({label,at:workflowSessionState.elapsed});const item=document.createElement('li');item.textContent=label+' · '+workflowSessionFormat(workflowSessionState.elapsed);document.querySelector('#workflowSessionLaps').append(item);workflowSessionDrive();}function workflowSessionStop(complete=false){clearInterval(workflowSessionState.timer);workflowSessionState.timer=null;workflowSessionState.phase=complete?'complete':'paused';workflowSessionToggle.textContent=complete?'Restart':'Continue round';workflowSessionToggle.setAttribute('aria-pressed','false');workflowSessionDrive();announce(complete?'Round complete for the study break timer':'Round paused');}function workflowSessionStart(){if(workflowSessionState.phase==='complete'){workflowSessionState.elapsed=0;workflowSessionState.checkpoints=[];document.querySelector('#workflowSessionLaps').replaceChildren();}workflowSessionState.phase='running';workflowSessionToggle.textContent='Pause round';workflowSessionToggle.setAttribute('aria-pressed','true');const bridge=workflowBridgeActivate();workflowSessionLap(bridge.summary);clearInterval(workflowSessionState.timer);workflowSessionState.timer=setInterval(()=>{workflowSessionState.elapsed+=1;if(workflowSessionState.elapsed>=workflowSessionState.limit){workflowSessionStop(true);return;}workflowSessionDrive();},1000);workflowSessionDrive();announce('Class Break Timer Round Started · '+bridge.summary);}workflowSessionToggle.addEventListener('click',()=>workflowSessionState.phase==='running'?workflowSessionStop():workflowSessionStart());workflowSessionLength.addEventListener('input',()=>{workflowSessionState.limit=Number(workflowSessionLength.value);workflowSessionState.elapsed=Math.min(workflowSessionState.elapsed,workflowSessionState.limit);workflowSessionDrive();});workflowSessionCore.addEventListener('keydown',event=>{if(event.key==='Enter'||event.key===' '){workflowSessionLap('Keyboard Interaction');}});workflowSessionCore.addEventListener('click',event=>{if(event.target.closest('[data-core-bridge]'))workflowSessionLap('Core action · '+workflowBridgeSummary());});document.addEventListener('visibilitychange',()=>{if(document.hidden&&workflowSessionState.phase==='running')workflowSessionStop();});workflowSessionDrive();
workflowBridgeReset();
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