vue style中变量样式

<div class="bumen" v-for="(item,bmmyIndex) in bmmyd_top4" :key="bmmyIndex">
        <div class="title">{{item.name}}</div>
        <div class="zhuzi_con">
                <div v-if="bmmyIndex == 0" class="zhuzi" :style="{'background-color':'#71C1C8','height':item.value + '%'}"></div>
                <div v-if="bmmyIndex == 1" class="zhuzi" :style="{'background-color':'#C5D6D0','height':item.value + '%'}"></div>
                   
         <div class="number">{{item.value}}</div>
</div>

<div id="container" :style="{ 'background-image':'url(' + mapbg + ')',width: '550px',height: '660px'}">