:root {
    /* Premium Dark Mode Palette from Main Site */
    --bg-color: #050505;
    --bg-gradient: radial-gradient(circle at top center, #1a1a1a 0%, #050505 80%);
    --text-color: #e0e0e0;
    --text-muted: #888888;
    --sidebar-bg: #111;

    /* Accents */
    --accent-color: #ffd700;
    --accent-glow: rgba(255, 215, 0, 0.4);
    --accent-gradient: linear-gradient(135deg, #ffd700, #ffaa00);
    --success-color: #27ae60;
    --error-color: #c0392b;

    /* Glassmorphism */
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.5);

    /* Typography */
    --font-serif: 'Playfair Display', serif;
    --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-color);
    background-image: var(--bg-gradient);
    background-attachment: fixed;
    margin: 0;
    display: flex;
    flex-direction: column;
    height: 100vh;
    color: var(--text-color);
}

.app-container {
    display: none;
    flex: 1;
    width: 100%;
    overflow: hidden;
}

/* Common Button Style */
.btn-common {
    padding: 10px 20px;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 0.9rem;
}

.btn-primary {
    background: var(--accent-gradient);
    color: #000;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px var(--accent-glow);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-color);
    border: 1px solid var(--glass-border);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: var(--accent-color);
}

/* Setup Screen Overlay */

#setupScreen {
    width: 100%;
    min-height: 100vh;
    background: var(--bg-color);
    display: flex;
    flex-direction: column;
    /* justify-content: center; removed to prevent top clipping */
    align-items: center;
    padding: 20px;
    box-sizing: border-box;
}

.upload-box {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--glass-shadow);
    text-align: center;
    max-width: 600px;
    width: 100%;
    margin: auto;
    /* Safe centering */
    box-sizing: border-box;
}

/* SEO & Intro Text Styles */
.intro-text {
    text-align: left;
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid var(--glass-border);
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.6;
}

.intro-text h3 {
    color: var(--text-color);
    font-size: 1.1rem;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.intro-text p {
    margin-bottom: 15px;
}

/* Footer Links Style */
.intro-footer {
    margin-top: 20px;
    font-size: 0.8rem;
    color: #666;
}

.intro-footer a {
    color: var(--text-muted);
    text-decoration: none;
    margin: 0 10px;
    transition: color 0.3s;
}

.intro-footer a:hover {
    color: var(--accent-color);
}

.upload-box h2 {
    font-family: var(--font-serif);
    color: var(--accent-color);
    margin-bottom: 20px;
}

.quiz-select {
    padding: 12px;
    font-size: 16px;
    border-radius: 8px;
    border: 1px solid var(--glass-border);
    background: rgba(0, 0, 0, 0.5);
    color: var(--text-color);
    width: 100%;
    max-width: 300px;
    margin-bottom: 20px;
    margin-top: 10px;
    outline: none;
}

.quiz-select:focus {
    border-color: var(--accent-color);
}

/* Sidebar for Navigation */
.sidebar {
    width: 280px;
    background: rgba(0, 0, 0, 0.6);
    border-right: 1px solid var(--glass-border);
    display: flex;
    flex-direction: column;
    padding: 15px;
    height: 100%;
    box-sizing: border-box;
    backdrop-filter: blur(10px);
}

.sidebar-header {
    padding-bottom: 10px;
    border-bottom: 1px solid var(--glass-border);
    margin-bottom: 10px;
    flex-shrink: 0;
}

.sidebar-header h3 {
    color: var(--accent-color);
    margin: 0 0 5px 0;
    font-size: 1.2rem;
    letter-spacing: 1px;
}

#stats {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.question-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 4px;
    overflow-y: auto;
    flex: 1;
    padding-right: 5px;
}

/* Custom Scrollbar */
.question-grid::-webkit-scrollbar {
    width: 6px;
}

.question-grid::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 3px;
}

.q-btn {
    padding: 8px 0;
    border: 1px solid var(--glass-border);
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-muted);
    cursor: pointer;
    border-radius: 6px;
    font-size: 11px;
    text-align: center;
    transition: all 0.2s;
}

.q-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    color: #fff;
}

.q-btn.active {
    border-color: var(--accent-color);
    color: var(--accent-color);
    box-shadow: 0 0 10px rgba(255, 215, 0, 0.2);
}

.q-btn.correct {
    border-color: var(--success-color);
    background: rgba(39, 174, 96, 0.2);
    color: #fff;
}

.q-btn.wrong {
    border-color: var(--error-color);
    background: rgba(192, 57, 43, 0.2);
    color: #fff;
}

/* Footer buttons container */
.sidebar-footer {
    margin-top: 20px;
    display: flex;
    flex-direction: row;
    gap: 10px;
    flex-shrink: 0;
    width: 100%;
}

.sidebar-footer button {
    flex: 1;
    padding: 10px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: bold;
    color: #fff;
    transition: opacity 0.2s;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 40px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
}

.quiz-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--glass-shadow);
    max-width: 800px;
    width: 100%;
    display: none;
    margin-bottom: 40px;
}

.header span {
    color: var(--text-muted);
    font-size: 0.9rem;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.question-text {
    font-size: 1.3rem;
    font-family: var(--font-serif);
    color: #fff;
    margin: 20px 0 30px 0;
    line-height: 1.6;
    border-left: 3px solid var(--accent-color);
    padding-left: 20px;
}

.options-container {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.option-label {
    display: flex;
    align-items: center;
    padding: 10px 20px;
    border: 1px solid var(--glass-border);
    background: rgba(255, 255, 255, 0.02);
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s;
    color: var(--text-color);
}

.option-label:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.2);
    transform: translateX(5px);
}

input[type="radio"] {
    margin-right: 15px;
    accent-color: var(--accent-color);
    transform: scale(1.2);
}

.option-label.correct-answer {
    background: rgba(39, 174, 96, 0.2);
    border-color: var(--success-color);
    color: #fff;
}

.option-label.wrong-answer {
    background: rgba(192, 57, 43, 0.2);
    border-color: var(--error-color);
    color: #fff;
}

.controls {
    margin-top: 40px;
    display: flex;
    justify-content: space-between;
    gap: 20px;
}

.controls button {
    min-width: 120px;
}

#errorMsg {
    color: var(--error-color);
    margin-top: 15px;
    font-weight: bold;
}

.score-board {
    margin-top: 30px;
    padding: 20px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 10px;
    text-align: center;
    border: 1px solid var(--glass-border);
    color: var(--text-color);
}

/* Responsive Design */
@media (max-width: 768px) {
    .app-container {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        height: auto;
        max-height: 35vh;
        border-right: none;
        border-bottom: 1px solid var(--glass-border);
        order: 2;
        padding: 15px;
    }

    .question-grid {
        max-height: 120px;
        grid-template-columns: repeat(8, 1fr);
    }

    .sidebar-footer {
        flex-direction: row;
    }

    .main-content {
        padding: 10px;
        order: 1;
    }

    .quiz-card {
        padding: 15px;
        margin-bottom: 10px;
    }

    .controls {
        flex-wrap: wrap;
        margin-top: 20px;
    }

    .controls button {
        flex: 1;
    }

    .upload-box {
        padding: 30px 20px;
    }
}