Styling the Upload Button

    // This targets the upload form's v-button.  Put it in the themes scss file. 
    .v-upload .v-button {
        color: red;
    }

     I use this one quite a bit, so the button becomes a 'link'.
    .v-upload .v-button {
        @extend .v-button-link;
    }

For those like me who would have enjoyed a little example... :)

In Java :

Upload attachButton = new Upload();
        attachButton.addStyleName("upload-with-icon");
        attachButton.setImmediate(true);
        attachButton.setButtonCaption("");

In css :

service.upload-with-icon {
    height: 100%;
}

service.upload-with-icon div {
    height: 100%;
}

service.upload-with-icon .v-button {
    background-image: url('image/button-icons/attachment.png');
    background-repeat: no-repeat;
    background-size: 23px 19px;
    background-position: center;
}