Nothing groundbreaking here just attractive, progressively enhanced CSS buttons. TODO: is there a way to get a gradient in Opera? Also the blur looks a bit crap in Opera. Either fix it or remove it (but only for Opera).

Pure CSS buttons

<style type="text/css>
p {
    margin-bottom:10px
}

button {
    border: 1px solid #ccc;
    color: #333;
    cursor: pointer;
    font-size: 12px;
    margin: 3px; /* ensures rooms for the blur */
    padding: 4px 20px;
    
    -khtml-border-radius: 25px;
    -moz-border-radius: 25px;
    -o-border-radius: 25px;
    -webkit-border-radius: 25px;
    border-radius: 25px;
    
    -khtml-text-shadow: -1px -1px 1px #ccc;
    -moz-text-shadow: -1px -1px 1px #ccc;
    -o-text-shadow: -1px -1px 1px #ccc;
    -webkit-text-shadow: -1px -1px 1px #ccc;
    text-shadow: -1px -1px 1px #ccc;
}

button,
button.disabled:hover {    
    -kthml-box-shadow: 0 0 2px #ccc;
    -moz-box-shadow: 0 0 2px #ccc;
    -o-box-shadow: 0 0 2px #ccc;
    -webkit-box-shadow: 0 0 2px #ccc;
    box-shadow: 0 0 2px #ccc;   
}

button,
button:active {
    background: #ffffff;
}

button,
button.disabled:active {    
    background: -moz-linear-gradient(top, #ffffff 0%, #e5e5e5 100%);
    background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#ffffff), color-stop(100%,#e5e5e5));    
    filter: progid:DXImageTransform.Microsoft.gradient( enabled='true', startColorstr=#ffffff, endColorstr=#e5e5e5 );  
}

button:hover {
    /* the blur doesn't look so great in Opera. Any ideas? */
    -kthml-box-shadow: 0 0 2px red;
    -moz-box-shadow: 0 0 2px red;
    -o-box-shadow: 0 0 2px red; /* Opera 10.6 seems to ignore this */
    -webkit-box-shadow: 0 0 2px red;
    box-shadow: 0 0 2px red; /* Opera 10.6 instead uses the native property but not very well */
}

button.disabled {
    color: #ccc;
    cursor: default;
    
    -khtml-text-shadow: -1px -1px 1px #000;
    -moz-text-shadow: none;
    -o-text-shadow: -1px -1px 1px #000;
    -webkit-text-shadow: -1px -1px 1px #000;
    text-shadow: none;       
}
</style>

<p><button type="submit">Submit</button></p>
<p><button type="submit" class="disabled">This button is disabled</button></p>