.yui3-spinner input.yui3-spinner-inputError  {
    background-color:red;
}

.yui3-spinner .yui3-spinner-up {
    background:transparent url(arrows.png) no-repeat 50% -3px;
}

.yui3-spinner .yui3-spinner-down {
    background:transparent url(arrows.png) no-repeat 50% -54px;
 }