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<!DOCTYPE html><html><head>  <meta http-equiv="content-type" content="text/html; charset=utf-8" />  <title>Simple styling of a simple document</title>  <style type="text/css">    html {color: black; background-color: white; }    h1 {color: gray;}    h2 {color: silver;}  </style></head><body> <h1>Plutonium</h1><p>Useful for many applications, plutonium can also be dangerous if improperly handled.</p> <h2>Safety Information</h2> <p class="warning">When handling plutonium, care must be taken to avoid the formation of a critical mass.</p><p>With plutonium, <span class="warning">the possibility of implosion isvery real, and must be avoided at all costs</span>. This can be accomplished by keeping the various masses separate.</p> <h3>Comments</h3><p>It’s best to avoid using plutonium <b>at all</b> if it can be avoided.</p> </body></html>