Ionic Item Class inheritance

      <ion-radio-group mode= 'ios' value='chairs'>
        <ion-item v-for='chair in chairs' v-bind:key='' lines='none'>
          <ion-label class="unselected-radio-button" style="color:#CACACC;  line-height: 24px; font-size: 16px; letter-spacing: -0.25px;">{{}} <span>{{showMetric ? inchesToMetric(chair.size) + 'cm' : chair.size + '"'}}</span></ion-label>
          <ion-radio slot='start' v-model='' @click='onClickRadio(chair.size)' style='width:23px;height:23px;border-radius:4px;border:3px solid #D3D7D9;'></ion-radio>

I have the following code and noticed that if I make a class called “unselected-radio-button” my styling gets overwritten by the style of “ion-item” I was wondering why that was. I have the exact same code as in line CSS and it works but if I just have the class it does not work.