<svg viewBox="0 0 700 130" xmlns="http://www.w3.org/2000/svg">
  <!-- Short Header Packet -->
  <text x="350" y="18" text-anchor="middle" font-family="'Space Mono', monospace" font-size="12" fill="#6366f1">Short Header Packet (1-RTT)</text>

  <!-- First byte -->
  <rect x="10" y="35" width="70" height="50" rx="3" fill="none" stroke="#6366f1" stroke-width="1.5"/>
  <text x="45" y="58" text-anchor="middle" font-family="'Space Mono', monospace" font-size="11" fill="#6366f1">01smmmmm</text>
  <text x="45" y="70" text-anchor="middle" font-family="'Space Mono', monospace" font-size="8" fill="#888">1 byte</text>

  <!-- DCID -->
  <rect x="80" y="35" width="150" height="50" rx="3" fill="none" stroke="#818cf8" stroke-width="1"/>
  <text x="155" y="58" text-anchor="middle" font-family="'Space Mono', monospace" font-size="10" fill="#818cf8">Dest Conn ID</text>
  <text x="155" y="70" text-anchor="middle" font-family="'Space Mono', monospace" font-size="8" fill="#888">length known</text>

  <!-- Encrypted: Packet Number + Payload -->
  <rect x="230" y="35" width="460" height="50" rx="3" fill="none" stroke="#888" stroke-width="1" stroke-dasharray="4 3"/>
  <text x="460" y="58" text-anchor="middle" font-family="'Space Mono', monospace" font-size="10" fill="#888">Packet Number + Payload</text>
  <text x="460" y="70" text-anchor="middle" font-family="'Space Mono', monospace" font-size="8" fill="#888">encrypted</text>

  <!-- Annotations -->
  <text x="120" y="110" text-anchor="middle" font-family="'Space Mono', monospace" font-size="9" fill="#888">&#x2190; unencrypted &#x2192;</text>
  <line x1="230" y1="100" x2="230" y2="92" stroke="#888" stroke-width="0.5"/>
</svg>
