.button a{
font: bold 12px Verdana, Arial, sans-serif;
text-decoration: none;
text-indent: 0px;
color: #FFFFCC; 
background: url( mybutton1.png );
display: block;
width: 135px;
line-height: 35px;
height: 38px;
TEXT-ALIGN: center;
}

.button a:hover{
background-position: 0px -38px;
text-decoration: none;
color: #FFFFFF;
}