:root {
    --primary-color: #2ecc71; /* Medical Green */
    --secondary-color: #3498db; /* Clinical Blue */
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-main: #2c3e50;
    --text-muted: #7f8c8d;
    --border-color: #e2e8f0;
    --error-color: #e74c3c;
    --success-color: #27ae60;
    --warning-color: #f1c40f;
    --border-radius: 16px;
    --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.app-container {
    width: 100%;
    max-width: 600px;
    margin: 0 auto;
}

/* Layout Screens */
.screen {
    display: none;
    opacity: 0;
    transform: translateY(20px);
    transition: var(--transition);
}

.screen.active {
    display: block;
    opacity: 1;
    transform: translateY(0);
}

.hidden {
    display: none !important;
}

/* Cards */
.card {
    background: var(--card-bg);
    padding: 2.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.title {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 1rem;
    text-align: center;
}

.subtitle {
    color: var(--text-muted);
    text-align: center;
    margin-bottom: 2rem;
}

/* Progress Bar */
#progress-container {
    margin-bottom: 2rem;
}

.progress-bar-wrapper {
    height: 8px;
    background: var(--border-color);
    border-radius: 10px;
    overflow: hidden;
    margin-bottom: 0.5rem;
}

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

.progress-text {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-weight: 500;
}

/* Quiz Styling */
.section-title {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--secondary-color);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.question-text {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 2rem;
}

.options-container {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.option-btn {
    padding: 1rem 1.5rem;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    background: transparent;
    cursor: pointer;
    text-align: left;
    font-size: 1rem;
    transition: var(--transition);
    display: flex;
    align-items: center;
}

.option-btn:hover {
    border-color: var(--secondary-color);
    background: rgba(52, 152, 219, 0.02);
}

.option-btn.selected {
    border-color: var(--secondary-color);
    background: rgba(52, 152, 219, 0.08);
    font-weight: 500;
}

/* Buttons */
.btn-container {
    margin-top: 2.5rem;
    display: flex;
    justify-content: space-between;
}

.btn {
    padding: 0.8rem 2rem;
    border-radius: 10px;
    border: none;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.btn-primary {
    background: var(--secondary-color);
    color: white;
    width: 100%;
}

.btn-primary:hover {
    filter: brightness(1.1);
    transform: translateY(-2px);
}

.btn-next {
    background: var(--primary-color);
    color: white;
}

.btn-next:disabled {
    background: var(--border-color);
    cursor: not-allowed;
    transform: none;
}

/* Results Styling */
.result-header {
    text-align: center;
    padding: 2rem;
    border-radius: var(--border-radius);
    margin-bottom: 2rem;
    color: white;
}

.result-header.green { background: var(--success-color); }
.result-header.yellow { background: var(--warning-color); color: #2c3e50; }
.result-header.red { background: var(--error-color); }

.result-score {
    font-size: 3rem;
    font-weight: 800;
    display: block;
}

.plan-card {
    background: white;
    padding: 2rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    margin-bottom: 1rem;
}

.plan-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
}

.plan-features {
    list-style: none;
    margin-top: 1rem;
}

.plan-features li {
    padding: 0.5rem 0;
    display: flex;
    align-items: flex-start;
    font-size: 0.95rem;
}

.plan-features li::before {
    content: "✓";
    color: var(--primary-color);
    margin-right: 10px;
    font-weight: bold;
}

/* Footer */
.app-footer {
    margin-top: 3rem;
    text-align: center;
}

.disclaimer {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-style: italic;
}

/* Mobile Adjustments */
@media (max-width: 480px) {
    .card { padding: 1.5rem; }
    .title { font-size: 1.5rem; }
    .question-text { font-size: 1.1rem; }
}