:root {
    --primary-bg: #ffffff;
    --secondary-bg: #f9f9f9;
    --text-color: #333333;
    --primary-color: #007bff;
    --border-color: #dddddd;
    --input-bg: #ffffff;
    --result-bg: #e9ecef;
}

[data-theme="dark"] {
    --primary-bg: #1a1a2e;
    --secondary-bg: #16213e;
    --text-color: #e0e0e0;
    --primary-color: #0f3460;
    --border-color: #555555;
    --input-bg: #2f3b52;
    --result-bg: #16213e;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--primary-bg);
    color: var(--text-color);
    line-height: 1.6;
    margin: 0;
    padding: 20px;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background-color: var(--secondary-bg);
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

header {
    text-align: center;
    margin-bottom: 30px;
}

header h1 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

main {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input[type="date"],
.form-group input[type="time"],
.form-group input[type="number"],
.form-group select {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: var(--input-bg);
    color: var(--text-color);
    box-sizing: border-box;
}

.radio-group {
    display: flex;
    gap: 20px;
    align-items: center;
}

.radio-group input[type="radio"] {
    margin-right: 5px;
}

.cta-button {
    width: 100%;
    padding: 15px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 4px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: background-color 0.3s;
}

.cta-button:hover {
    background-color: #0056b3;
}

.result-section h2 {
    color: var(--primary-color);
    text-align: center;
}

.result-display {
    background-color: var(--result-bg);
    padding: 20px;
    border-radius: 8px;
    text-align: center;
    font-size: 1.2rem;
    font-weight: 500;
}

footer {
    text-align: center;
    margin-top: 30px;
    font-size: 0.9rem;
    color: #888;
}

.theme-switcher {
    margin-top: 10px;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
}

/* Responsive Design */
@media (min-width: 768px) {
    main {
        flex-direction: row;
    }
    .input-section, .result-section {
        flex: 1;
    }
    .result-section {
       align-self: center;
    }
}