Panel header

<div style="width:400px;border:1px solid var(--border-default);border-radius:6px;overflow:hidden">
  <div class="atlas-panel-header">
    <span class="atlas-panel-title">Inspector</span>
  </div>
  <div style="padding:12px;font-size:13px;color:var(--text-secondary)">Panel body content</div>
</div>

<div style="width:400px;border:1px solid var(--border-default);border-radius:6px;overflow:hidden">
  <div class="atlas-panel-header" style="display:flex;align-items:center;justify-content:space-between">
    <span style="display:flex;align-items:center;gap:6px"><span class="atlas-dot atlas-dot-info"></span><span class="atlas-panel-title">Build log</span></span>
    <button class="atlas-btn atlas-btn-icon" aria-label="Close"><svg width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5"><path d="M18 6 6 18M6 6l12 12"/></svg></button>
  </div>
  <div style="padding:12px;font-size:13px;color:var(--text-secondary)">Contents…</div>
</div>