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<style>
div.ust {border-top:2px solid red;}
div.alt {border-bottom:2px solid red;}
div.sol {border-left:2px solid red;}
div.sag {border-right:2px solid red;}
div.koyugri {background:#333}
div.acikgri {background:#ddd}
</style>

<div class="ust koyugri">
a
</div><br><br>

<div class="alt sol acikgri">
b
</div><br><br>

<div class="sag alt koyugri">
c
</div><br><br>

<div class="ust alt sag acikgri">
d
</div><br><br>

<div class="sol sag koyugri">
e
</div><br><br>

<div class="ust alt sag sol acikgri">
f
</div><br><br>

<div class="ust alt sag sol koyugri">
g
</div>