input{margin-bottom:20px;padding:10px 20px}.calculator{border:1px solid #ccc;border-radius:5px;margin:0 auto;max-width:300px;padding:20px}.display{font-size:18px;margin-bottom:10px;padding:10px;text-align:right;width:100%}.buttons{display:grid;gap:10px;grid-template-columns:repeat(4,1fr)}button{background-color:#fff;font-size:18px;padding:10px;width:100%}.clear-button{margin-top:10px;width:100%}.small-text{font-size:14px}