Como mudar tipo de letra de posts do Blogger

<div class="NombreDiv">
Lorem Ipsum is simply dummy text of the printing and typesetting industry.
Lorem Ipsum has been the industry's standard dummy text ever since the 1500s
</div>

.NombreDiv{
  font-size: 22px;
  color: #555;
  font-family: arial;
  font-style: italic;
}

<style>
@font-face{font-family:'Mutlu Ornamental';src:url('Mutlu_Ornamental.woff')format('woff');}
</style>


<div id='letra'>
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0 1 2 3 4 5 6 7 8 9 . : , ; ( ) * ! ? ' @ # < > $ % & ^ + - = ~
</div>

#letra{
font-family:'Mutlu Ornamental';
font-size:26px;
font-style:italic;
}