body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    background-color: #f5f5f5;
    color: #333;
}

header {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-bottom: 2rem;
}

header h1 {
    margin: 0 0 1rem 0;
    font-weight: 700;
}

header p {
    margin: 0;
    opacity: 0.9;
}

main {
    max-width: 600px;
    margin: 0 auto;
    padding: 0 20px;
}

.calculator {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.input-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

input, select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
    box-sizing: border-box;
}

button {
    background-color: #27ae60;
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    border-radius: 4px;
    cursor: pointer;
    width: 100%;
    font-weight: 500;
}

button:hover {
    background-color: #219a52;
}

.result {
    margin-top: 1.5rem;
    padding: 1rem;
    background-color: #e8f5e9;
    border-radius: 4px;
    display: none;
}

footer {
    background-color: #34495e;
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: 3rem;
}

.footer-links {
    margin-bottom: 1rem;
}

.footer-links a {
    color: #ecf0f1;
    margin: 0 1rem;
    text-decoration: none;
}

.footer-links a:hover {
    text-decoration: underline;
}