:root {
    --primary-color: #007bff; /* Blue */
    --secondary-color: #0056b3; /* Darker Blue */
    --background-color: #f8f9fa; /* Light Gray/White */
    --text-color: #333;
    --text-light: #666;
    --white: #ffffff;
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

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

body {
    font-family: var(--font-family);
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    background-color: var(--white);
    padding: 1rem 2rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

main {
    flex: 1;
    padding: 2rem;
    max-width: 800px;
    margin: 0 auto;
    width: 100%;
}

.container {
    background-color: var(--white);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    margin-bottom: 2rem;
}

h1, h2, h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

p {
    margin-bottom: 1rem;
    color: var(--text-color);
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: var(--white);
    text-decoration: none;
    border-radius: var(--border-radius);
    border: none;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s ease;
    text-align: center;
}

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

.btn-secondary {
    background-color: #6c757d;
}

.btn-secondary:hover {
    background-color: #5a6268;
}

/* Progress Bar */
.progress-container {
    width: 100%;
    background-color: #e9ecef;
    border-radius: var(--border-radius);
    margin-bottom: 2rem;
    height: 10px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: var(--primary-color);
    width: 0%;
    transition: width 0.5s ease;
}

/* Question Styles */
.options {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
}

.option-btn {
    background-color: var(--white);
    border: 2px solid #e9ecef;
    color: var(--text-color);
    padding: 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    text-align: left;
    transition: all 0.3s ease;
}

.option-btn:hover, .option-btn.selected {
    border-color: var(--primary-color);
    background-color: #e7f1ff;
    color: var(--primary-color);
}

.nav-buttons {
    display: flex;
    justify-content: space-between;
    margin-top: 2rem;
}

/* Footer */
footer {
    background-color: var(--white);
    padding: 2rem;
    text-align: center;
    margin-top: auto;
    border-top: 1px solid #e9ecef;
}

footer a {
    color: var(--text-light);
    text-decoration: none;
    margin: 0 0.5rem;
    font-size: 0.9rem;
}

footer a:hover {
    color: var(--primary-color);
}

.disclaimer {
    font-size: 0.8rem;
    color: #999;
    margin-top: 1rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Responsive */
@media (max-width: 600px) {
    main {
        padding: 1rem;
    }
    
    .container {
        padding: 1.5rem;
    }
    
    .nav-buttons {
        flex-direction: column;
        gap: 1rem;
    }
    
    .btn {
        width: 100%;
    }
}

/* Article Content */
.article-content {
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid #eee;
}

.article-content h2 {
    font-size: 1.5rem;
}

.article-content p {
    font-size: 1rem;
    line-height: 1.8;
    color: #444;
}