input#give-amount

 {
    font-size: 28px !important;
 }


form[id*=give-form] .give-donation-amount #give-amount, form[id*=give-form] .give-donation-amount #give-amount-text
 {
    font-size: 28px !important;
 }

.choose-amount .give-donation-amount .give-amount-top
 {
    font-size: 28px !important;
 }