:root{
    --header-bg:#222;
    --muted:#999;
    --accent:#007bff;
    --panel-width:360px;
  }

  *{box-sizing:border-box}
  body{margin:0;height:100vh;display:flex;flex-direction:column;font-family:Arial,Helvetica,sans-serif;background:#fafafa;color:#111}
  header{background:var(--header-bg);color:#fff;padding:10px;display:flex;flex-wrap:wrap;gap:8px;align-items:center;z-index:50}
  header button, header label{background:#444;color:#fff;border:none;padding:6px 12px;cursor:pointer;border-radius:4px}
  header button:hover{background:#666}
  .dropdown{position:relative;display:inline-block}
  .dropdown-content{display:none;position:absolute;background:#fff;min-width:220px;box-shadow:0 8px 16px rgba(0,0,0,.2);z-index:1000;flex-direction:column;border-radius:6px;overflow:hidden}
  .dropdown-content button{width:100%;padding:8px 12px;border:none;background:#fff;text-align:left;cursor:pointer;color:#000}
  .dropdown-content button:hover{background:#f2f2f2}
  .dropdown:hover .dropdown-content{display:flex;flex-direction:column}
  .view-switcher{background:#f4f4f4;border-bottom:1px solid #ccc;padding:6px;display:flex;justify-content:center;gap:6px}
  .view-switcher button{padding:6px 14px;border:1px solid #aaa;background:#fff;cursor:pointer;border-radius:4px}
  .view-switcher button.active{background:var(--accent);color:#fff;border-color:#0056b3}
  main{flex:1;display:flex;overflow:hidden;transition:all .25s ease;position:relative}
  .editor-container{flex:1;display:flex;flex-direction:column;border-right:2px solid #ccc;min-width:320px}
  .tabs{display:flex;background:#ddd}
  .tabs button{flex:1;padding:8px;border:none;cursor:pointer;background:#ccc}
  .tabs button.active{background:#fff;border-bottom:2px solid var(--accent)}
  .tab-content{flex:1;display:none;height:100%}
  .tab-content.active{display:block}
  iframe{flex:1;border:none;background:#fff}
  .console{background:#111;color:#0f0;padding:8px;font-family:monospace;font-size:13px;height:120px;overflow:auto;position:relative}
  .console::before{content:"Console output will appear here...";color:var(--muted);position:absolute;top:6px;left:6px;pointer-events:none;display:block}
  .console.has-content::before{display:none}
  .split .editor-container{display:flex}
  .split iframe{display:block}
  .code-only .editor-container{flex:1}
  .code-only iframe{display:none}
  .preview-only .editor-container{display:none}
  .preview-only iframe{flex:1}
  .cm-editor{height:100%;font-family:monospace;font-size:14px}
  #htmlEditor,#cssEditor,#jsEditor{height:100%}
  .CodeMirror{white-space:pre-wrap!important;word-wrap:break-word!important}

  @media (max-width:768px){
    main{flex-direction:column}
    .editor-container{border-right:none;border-bottom:2px solid #ccc}
  }

  /* Lint */
  .CodeMirror-lint-markers{width:16px!important}
  .CodeMirror-lint-marker-error{color:#ff4d4d!important;font-size:14px}
  .CodeMirror-lint-marker-warning{color:#ffcc00!important;font-size:14px}
  .CodeMirror-lint-tooltip{background:#222!important;color:#eee!important;border:1px solid #444!important;font-size:12px!important;padding:4px 6px!important;border-radius:4px;z-index:9999}

  /* Premium Modal */
  #premiumModal{position:fixed;inset:0;display:none;align-items:center;justify-content:center;background:rgba(0,0,0,.55);z-index:2000}
  #premiumModal .card{background:#fff;padding:18px;border-radius:10px;max-width:420px;width:92%;text-align:left;box-shadow:0 12px 40px rgba(0,0,0,.35)}
  #premiumModal h3{margin:0 0 8px}
  #premiumModal p{margin:0 0 12px;color:#333}
  #premiumModal .card .actions{display:flex;gap:8px;justify-content:flex-end}
  #premiumModal button.learn{background:var(--accent);color:#fff;border:none;padding:8px 12px;border-radius:6px;cursor:pointer}
  #premiumModal button.close{background:#eee;color:#333;border:none;padding:8px 12px;border-radius:6px;cursor:pointer}

  /* History Drawer (modern sliding panel) */
  #historyPanel{position:fixed;top:0;right:0;height:100%;width:var(--panel-width);transform:translateX(110%);transition:transform .28s cubic-bezier(.2,.9,.2,1);z-index:2500;box-shadow:-16px 0 40px rgba(0,0,0,.25);background:#fff;display:flex;flex-direction:column}
  #historyPanel.open{transform:translateX(0)}
  #historyPanel .panel-header{display:flex;align-items:center;justify-content:space-between;padding:12px 14px;border-bottom:1px solid #eee}
  #historyPanel .panel-header h4{margin:0;font-size:16px}
  #historyPanel .panel-body{padding:10px;overflow:auto;flex:1}
  .history-entry{padding:10px;border-radius:8px;border:1px solid #eee;margin-bottom:10px;display:flex;gap:8px;align-items:flex-start}
  .history-meta{flex:1}
  .history-meta small{display:block;color:var(--muted);font-size:12px}
  .history-meta p{margin:6px 0 0;font-size:13px;color:#222;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:240px}
  .history-actions{display:flex;flex-direction:column;gap:6px}
  .history-actions button{padding:6px 8px;border-radius:6px;border:none;cursor:pointer}
  .btn-restore{background:var(--accent);color:#fff}
  .btn-delete{background:#eee;color:#333}

  /* subtle overlay when panel open */
  #panelOverlay{position:fixed;inset:0;background:rgba(0,0,0,.25);z-index:2400;display:none}
  #panelOverlay.visible{display:block}