h1,label{color:#333}.container{max-width:600px;margin:20px auto;padding:20px;box-shadow:0 0 10px rgba(0,0,0,.1)}h1{text-align:center}label{font-size:16px}button,input{width:100%;padding:12px;margin:10px 0;font-size:16px;border:1px solid #ccc;border-radius:4px}button{background-color:#4caf50;color:#fff;border:none;cursor:pointer}button:hover{background-color:#45a049}.result{margin-top:20px;font-size:18px}@media (max-width:600px){.container{padding:15px;width:97%}button,input{font-size:14px;padding:10px}.result{font-size:16px}}