Click on the orange arrow from the field to add a class like below or a custom class :
<ol><li>input-mini</li><li>input-small</li><li>input-medium</li><li>input-large</li><li>input-xlarge</li><li>input-xxlarge</li></ol>
Click on the orange arrow from the field to add a class like below or a custom class :
<ol><li>input-mini</li><li>input-small</li><li>input-medium</li><li>input-large</li><li>input-xlarge</li><li>input-xxlarge</li></ol>