:root {
    --primary-color: #4CAF50;
    --secondary-color: #45a049;
    --background-color: #f4f4f4;
    --text-color: #333;
    --border-radius: 8px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    background-color: var(--background-color);
    color: var(--text-color);
}

.container {
    max-width: 800px;
    margin: 2rem auto;
    padding: 2rem;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 2rem;
}

.calculator-form {
    display: grid;
    gap: 1.5rem;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

label {
    font-weight: 600;
    color: var(--text-color);
}

input {
    padding: 0.8rem;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
}

input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(76, 175, 80, 0.2);
}

button {
    background-color: var(--primary-color);
    color: white;
    padding: 1rem;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    transition: background-color 0.3s ease;
}

button:hover {
    background-color: var(--secondary-color);
}

.results {
    margin-top: 2rem;
    padding: 1.5rem;
    background: #f9f9f9;
    border-radius: var(--border-radius);
    display: none;
}

.results.active {
    display: block;
}

.results h2 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.ai-recommendation {
    margin-top: 1.5rem;
    padding: 1rem;
    background: #e8f5e9;
    border-radius: var(--border-radius);
    border-left: 4px solid var(--primary-color);
}

@media (max-width: 600px) {
    .container {
        margin: 1rem;
        padding: 1rem;
    }
}