.calculator{font-family:"Segoe UI",Tahoma,Geneva,Verdana,sans-serif;background-color:#fff;border-radius:12px;box-shadow:0 4px 20px rgba(0,0,0,.1);padding:30px 40px;width:350px;text-align:center;color:#333}.calculator h1{font-size:1.6em;margin-bottom:20px;color:#222}.calculator label{display:block;font-weight:500;margin-top:15px;text-align:left}.calculator input{width:100%;padding:10px;margin-top:5px;font-size:1em;border:1px solid #ccc;border-radius:6px;transition:border-color .3s ease}.calculator input:focus{border-color:#007bff;outline:none}.calculator button{background-color:#007bff;color:#fff;border:none;padding:12px 20px;font-size:1em;border-radius:6px;cursor:pointer;margin-top:20px;transition:background-color .3s ease;width:100%}.calculator button:hover{background-color:#0056b3}.calculator .result{margin-top:25px;font-size:1.3em;font-weight:700;color:#007bff}.calculator .note{margin-top:15px;font-size:.85em;color:#666}