body{text-align:center;font-weight:700}button,input{padding:10px;text-align:center;border-radius:5px;font-weight:700;font-size:1.3rem}input{width:10%;background-color:#add8e6}button{margin:10px 20px}button.add{background-color:#228b22;color:#fff}button.sub{background-color:red;color:#fff}