body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-color: #f4f7f6; /* Light gray-blue background */
}

.calculator-container {
    background-color: #ffffff;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    width: 450px;
    text-align: center;
}

h1 {
    color: #00796b; /* Teal color */
    font-size: 1.8em;
    margin-bottom: 5px;
}

p:first-of-type {
    color: #555;
    margin-bottom: 25px;
    font-size: 0.95em;
}

.input-grid {
    display: flex;
    justify-content: space-between;
    gap: 20px;
    margin-bottom: 20px;
}

.input-group {
    flex-grow: 1;
    text-align: left;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
    color: #333;
}

input[type="number"] {
    width: 90%;
    padding: 10px;
    border: 1px solid #b2dfdb; /* Light teal border */
    border-radius: 5px;
    font-size: 16px;
}

input[type="number"]:focus {
    border-color: #00796b;
    outline: none;
}

.button-group {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
}

.button-group button {
    padding: 12px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1em;
    flex-grow: 1;
    transition: background-color 0.3s;
}

.calculate-btn {
    background-color: #00796b; /* Teal */
    color: white;
}

.calculate-btn:hover {
    background-color: #004d40;
}

.clear-btn {
    background-color: #ff6f61; /* Coral */
    color: white;
}

.clear-btn:hover {
    background-color: #c73838;
}

.result-display {
    margin-top: 25px;
    padding: 15px;
    background-color: #e0f2f1;
    border: 1px solid #b2dfdb;
    border-radius: 8px;
    text-align: left;
}

.result-display h2 {
    margin: 0 0 10px 0;
    color: #00796b;
    font-size: 1.3em;
}

.result-display p {
    margin: 12px 0;
    font-size: 1.1em;
    color: #333;
}

.result-display span {
    font-weight: bold;
    color: #000;
}

#error-message {
    color: red;
    font-weight: bold;
    margin-top: 15px;
    text-align: center;
}