<svg width="900" height="900" viewBox="0 0 900 900" xmlns="http://www.w3.org/2000/svg">
 
  <!-- Background -->
  <rect width="900" height="900" fill="white"/>
 
  <!-- Title -->
  <text x="450" y="70" font-family="Arial" font-size="34" text-anchor="middle">
    Inverted Star — Layer Structure (v1.0)
  </text>
 
  <!-- Layer circles -->
  <!-- L1: Surface -->
  <circle cx="450" cy="450" r="300" fill="none" stroke="#4A90E2" stroke-width="6"/>
  <text x="450" y="150" font-family="Arial" font-size="26" text-anchor="middle" fill="#4A90E2">
    L₁ — Surface Layer
  </text>
 
  <!-- L2: Mid -->
  <circle cx="450" cy="450" r="200" fill="none" stroke="#417505" stroke-width="6"/>
  <text x="450" y="260" font-family="Arial" font-size="26" text-anchor="middle" fill="#417505">
    L₂ — Mid‑Layer
  </text>
 
  <!-- L3: Deep -->
  <circle cx="450" cy="450" r="100" fill="none" stroke="#9013FE" stroke-width="6"/>
  <text x="450" y="360" font-family="Arial" font-size="26" text-anchor="middle" fill="#9013FE">
    L₃ — Deep Layer
  </text>
 
  <!-- Inversion singularity -->
  <circle cx="450" cy="450" r="28" fill="none" stroke="#9013FE" stroke-width="4"/>
  <text x="450" y="450" font-family="Arial" font-size="40" text-anchor="middle" fill="#9013FE" dominant-baseline="middle">
    ✧
  </text>
 
  <!-- Propagation arrows -->
  <defs>
    <marker id="arrow" markerWidth="10" markerHeight="10" refX="6" refY="3" orient="auto">
      <polygon points="0 0, 6 3, 0 6" fill="#333"/>
    </marker>
  </defs>
 
  <!-- L3 → L2 -->
  <line x1="450" y1="350" x2="450" y2="250"
        stroke="#9013FE" stroke-width="4" marker-end="url(#arrow)"/>
  <text x="480" y="300" font-family="Arial" font-size="20" fill="#9013FE">Propagation</text>
 
  <!-- L2 → L1 -->
  <line x1="450" y1="250" x2="450" y2="150"
        stroke="#417505" stroke-width="4" marker-end="url(#arrow)"/>
 
  <!-- Silence boundary -->
  <circle cx="450" cy="450" r="350" fill="none" stroke="#999" stroke-width="3" stroke-dasharray="10 10"/>
  <text x="450" y="820" font-family="Arial" font-size="24" text-anchor="middle" fill="#555">
    Silence Boundary (∂Ø)
  </text>
 
  <!-- Labels for explanation -->
  <text x="450" y="500" font-family="Arial" font-size="22" text-anchor="middle" fill="#333">
    Inversion originates at L₃ and propagates outward
  </text>
 
</svg>