body {
    font-family: Arial;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background: #f0f2f5;
}
.container {
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    width: 300px;
}
div {
    margin-bottom: 15px;
}
label {
    display: inline-block;
    width: 100px;
}
input {
    width: 150px;
    padding: 5px;
    border: 1px solid #ddd;
    border-radius: 4px;
}
button {
    background: #007bff;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    width: 100%;
}
.result {
    margin-top: 20px;
    font-size: 1.2em;
    text-align: center;
}