Demo space system color-scheme detection
Detect system color schemes in a presentation-room scenario: includes real content, interactive controls, clear status feedback, and responsive layouts.
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<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Demo space system color-scheme detection</title>
<style>
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</style>
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<body data-aesthetic="dashboard" data-composition="field-index">
<main class="page">
<header class="mast"><div><span class="eyebrow">dashboard / System Color Scheme Check / BEGINNER</span><h1>Demo space system color-scheme detection</h1><p class="intro">Detect system color schemes in a presentation-room scenario: includes real content, interactive controls, clear status feedback, and responsive layouts.</p></div><span class="scenario">Demo space</span></header>
<div class="composition-index"><section class="demo" aria-label="Presentation Area System Color Scheme Detection Interaction Zone"><div class="workflow-session"><header class="session-command"><div><span class="eyebrow">Demo Space SESSION</span><h2>Demo Timer Station</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 Presentation</button></header><div id="workflowSessionProgress" role="progressbar" aria-label="Demo 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:browser-media-device-color-scheme --><div id="schemeLab" class="scheme-lab" data-scheme="system"><aside><span class="eyebrow">COLOR SCHEME</span><h2>Presentation Space Color Preview</h2><fieldset id="schemeChoices"><legend>Display Mode</legend><label><input type="radio" name="scheme" value="system" checked>Follow system</label><label><input type="radio" name="scheme" value="light">Forced light mode</label><label><input type="radio" name="scheme" value="dark">Force dark mode</label></fieldset><label><input id="schemeContrast" type="checkbox" data-core-bridge="browser-media-device-color-scheme">Enhanced edge contrast</label></aside><section><header><i></i><i></i><i></i><output id="schemeDetected">Detect system preferences</output></header><article><span class="eyebrow">LIVE PREVIEW</span><h3>Theme switching preserves content structure</h3><p>Color roles, boundaries, and focus styles change together.</p><button id="schemeSample" class="action" type="button">Switch sample state</button></article><ul id="schemeTokens"><li><i></i>Page</li><li><i></i>Text</li><li><i></i>Emphasis</li></ul></section></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><aside class="index-mark" aria-hidden="true"><strong>05</strong><span>FIELD INDEX for Presentation Spaces</span></aside></div>
</main>
<script>
'use strict';
const statusOutput = document.querySelector('#status');
const announce = message => { statusOutput.textContent = message; };
/* 11DZ_CORE_SCRIPT_START:browser-media-device-color-scheme */
const schemeLab=document.querySelector('#schemeLab');const systemScheme=matchMedia('(prefers-color-scheme: dark)');const schemeState={choice:'system',contrast:false,selected:false};function resolveScheme(){const resolved=schemeState.choice==='system'?(systemScheme.matches?'dark':'light'):schemeState.choice;schemeLab.dataset.scheme=schemeState.choice;schemeLab.dataset.resolved=resolved;schemeLab.dataset.contrast=String(schemeState.contrast);document.querySelector('#schemeDetected').textContent='System '+(systemScheme.matches?'Dark':'Light')+' · Current '+(resolved==='dark'?'Dark':'Light');document.querySelector('.scheme-lab article').classList.toggle('is-selected',schemeState.selected);announce('Preview switched to'+(resolved==='dark'?'Dark':'Light')+'Plan');}document.querySelectorAll('[name="scheme"]').forEach(input=>input.addEventListener('change',()=>{schemeState.choice=input.value;resolveScheme();}));document.querySelector('#schemeContrast').addEventListener('change',event=>{schemeState.contrast=event.currentTarget.checked;resolveScheme();});document.querySelector('#schemeSample').addEventListener('click',()=>{schemeState.selected=!schemeState.selected;resolveScheme();});systemScheme.addEventListener?.('change',()=>{if(schemeState.choice==='system')resolveScheme();});resolveScheme();
/* 11DZ_CORE_SCRIPT_END */
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workflowBridgeReset();
</script>
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