<div class="border-top:2px solid red;background:#333">
a
</div><br><br>

<div class="border-bottom:2px solid red;border-left:2px solid red; background:#ddd">
b
</div><br><br>

<div class="border-bottom:2px solid red;border-right:2px solid red; background:#333">
c
</div><br><br>

<div class="border-top:2px solid red;border-bottom:2px solid red; border-right:2px solid red; background:#ddd">
d
</div><br><br>

<div class="border-left:2px solid red;border-right:2px solid red;background:#333">
e
</div><br><br>

<div class="border-top:2px solid red;border-bottom:2px solid red;border-left:2px solid red;border-right:2px solid red; background:#ddd">
f
</div><br><br>

<div class="border-top:2px solid red;border-bottom:2px solid red;border-left:2px solid red;border-right:2px solid red;background:#333">
g
</div>

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