I am attempting to add a card with vue and vuetify that will take up the space in my container using v-flex to create a horizontal card that acts the same way vertically. I have attempted to add a height style of 100%, using fill-height, child-flex, etc but I cannot get the size of the card to fill the container. What is the correct way to adjust the height? 

ref: <https://vuetifyjs.com/en/components/cards>

```
<div id="app">
  <v-app id="inspire">
    <v-toolbar color="green" dark fixed app>
      <v-toolbar-title>My Application</v-toolbar-title>
    </v-toolbar>
    <v-content >
      <v-container fluid fill-height >
        <v-layout
          justify-center
          align-center 
        >
          <v-flex text-xs-center >
              <v-card class="elevation-20" >
              <v-toolbar dark color="primary">
                <v-toolbar-title>I want this to take up the whole space with slight padding</v-toolbar-title>
                <v-spacer></v-spacer>
              </v-toolbar>
              <v-card-text>

              </v-card-text>

            </v-card>
          </v-flex>
        </v-layout>
      </v-container>
    </v-content>
    <v-footer color="green" app inset>
      <span class="white--text">&copy; 2018</span>
    </v-footer>
  </v-app>
</div>

```

example: <https://codepen.io/anon/pen/LmVJKx>