button style css
<div>
<style scoped="">
.button-xsmall {
font-size: 70%;
}
.button-small {
font-size: 85%;
}
.button-large {
font-size: 110%;
}
.button-xlarge {
font-size: 125%;
}
</style>
<button class="button-xsmall pure-button">Extra Small Button</button>
<button class="button-small pure-button">Small Button</button>
<button class="pure-button">Regular Button</button>
<button class="button-large pure-button">Large Button</button>
<button class="button-xlarge pure-button">Extra Large Button</button>
</div>