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    <style>
      @media (prefers-color-scheme: dark) {
        .bg { fill: #1a1a1a; }
        .text { fill: #ffffff; }
      }
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        .bg { fill: #2c3e50; }
        .text { fill: #ffffff; }
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  <text class="text" x="50" y="68" font-family="Arial, sans-serif" font-size="48" font-weight="bold" text-anchor="middle">NC</text>
</svg>
