<div class="ExpandableBox">
  <h3><a href="#Section1">Title 1</a></h3>
  <div id="Section1"><p>1 It replaces all weapon lights except the ones for M9 pistols or similar (i think).</p></div>
</div>
<div class="ExpandableBox">
  <h3><a href="#Section2">Title 2</a></h3>
  <div id="Section2"><p>2 It replaces all weapon lights except the ones for M9 pistols or similar (i think).</p></div>
</div>
<div class="ExpandableBox">
  <h3><a href="#Section3">Title 3</a></h3>
  <div id="Section3"><p>3 It replaces all weapon lights except the ones for M9 pistols or similar (i think).</p></div>
</div>

#Section1,
#Section2,
#Section3 {
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}

#Section1:target,
#Section2:target,
#Section3:target {
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