jsp頁面判定某個變量值的時候改變顏色

<td>
<c:if test="${v.price>'15' }">
<font color="yellow">${v.price }</font>
</c:if>
<c:if test="${v.price<'0' }">
<font color="red">${v.price }</font>
</c:if>
<c:if test="${v.price>='0'and v.price<='15' }">
<font color="black">${v.price }</font>
</c:if>
</td>