body {
    font-family: 'Poppins', sans-serif;
    background: linear-gradient(135deg, #2196f3, #21cbf3);
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    color: #ffffff;
}

.calculator {
    background: #ffffff;
    padding: 30px 40px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.3);
    width: 450px;
    max-width: 90%;
    box-sizing: border-box;
}

h1 {
    font-size: 24px;
    color: #333333;
}

p {
    color: #555555;
    font-size: 14px;
    margin-bottom: 20px;
}

.input-group {
    margin-bottom: 15px;
}

label {
    display: block;
    font-size: 14px;
    color: #333333;
    margin-bottom: 5px;
}

input {
    width: 100%;
    padding: 8px;
    font-size: 14px;
    border: 1px solid #cccccc;
    border-radius: 5px;
}

button {
    background: #4caf50;
    color: #ffffff;
    padding: 10px 15px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 14px;
    transition: background 0.3s;
}

button:hover {
    background: #388e3c;
}

.result {
    margin-top: 20px;
    font-size: 16px;
    color: #333333;
}