body {
    font-family: Arial, sans-serif;
    background: linear-gradient(135deg, #2b5876, #4e4376);
    color: white;
    text-align: center;
    margin: 0;
    padding: 0;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.calculator {
    background-color: rgba(0, 0, 0, 0.8);
    border-radius: 15px;
    padding: 20px 30px;
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.2);
}

h1 {
    margin-bottom: 10px;
    font-size: 26px;
    color: #84cef5;
}

p {
    margin-bottom: 15px;
    font-size: 16px;
}

.input-section label {
    display: block;
    margin: 10px 0 5px;
    font-size: 14px;
    color: #ccc;
}

input {
    padding: 10px;
    width: calc(100% - 20px);
    margin-bottom: 10px;
    border: none;
    border-radius: 5px;
    font-size: 16px;
}

.tooltip {
    font-size: 12px;
    color: #aaa;
    display: block;
    margin-bottom: 10px;
}

button {
    padding: 10px 20px;
    background-color: #84cef5;
    border: none;
    border-radius: 5px;
    font-size: 16px;
    color: white;
    cursor: pointer;
    margin: 5px;
    transition: transform 0.3s ease;
}

button:hover {
    transform: scale(1.1);
    background-color: #67b3e1;
}

#output {
    margin-top: 20px;
}

#presentValue {
    font-size: 18px;
    font-weight: bold;
}

@media (max-width: 768px) {
    body {
        padding: 20px;
    }
}