/* ═══════════════════════════════════════════
   GCP PCA Exam Prep — Design System
   ═══════════════════════════════════════════ */

/* ── CSS Variables / Tokens ── */
:root {
    --bg-primary: #0a0e1a;
    --bg-secondary: #111827;
    --bg-card: rgba(17, 24, 39, 0.7);
    --bg-card-hover: rgba(30, 41, 59, 0.8);
    --bg-glass: rgba(255, 255, 255, 0.04);
    --bg-glass-hover: rgba(255, 255, 255, 0.08);

    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --text-inverse: #0f172a;

    --accent-blue: #4285F4;
    --accent-green: #34A853;
    --accent-yellow: #FBBC05;
    --accent-red: #EA4335;
    --accent-cyan: #00bcd4;
    --accent-purple: #a78bfa;

    --gradient-primary: linear-gradient(135deg, #4285F4, #34A853);
    --gradient-warm: linear-gradient(135deg, #FBBC05, #EA4335);
    --gradient-cool: linear-gradient(135deg, #4285F4, #a78bfa);
    --gradient-success: linear-gradient(135deg, #34A853, #00bcd4);
    --gradient-danger: linear-gradient(135deg, #EA4335, #ff6b6b);

    --border-subtle: rgba(255, 255, 255, 0.06);
    --border-medium: rgba(255, 255, 255, 0.12);
    --border-accent: rgba(66, 133, 244, 0.4);

    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 24px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 48px rgba(0, 0, 0, 0.5);
    --shadow-glow-blue: 0 0 30px rgba(66, 133, 244, 0.15);
    --shadow-glow-green: 0 0 30px rgba(52, 168, 83, 0.15);
    --shadow-glow-red: 0 0 30px rgba(234, 67, 53, 0.15);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 999px;

    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ── Reset & Base ── */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.6;
}

/* ── Particle Canvas ── */
#particles-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
    opacity: 0.6;
}

/* ── Screen System ── */
.screen {
    display: none;
    position: relative;
    z-index: 1;
    min-height: 100vh;
}
.screen.active {
    display: block;
    animation: fadeIn 0.4s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes scaleIn {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}

@keyframes shimmer {
    0% { background-position: -200% center; }
    100% { background-position: 200% center; }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

@keyframes countPop {
    0% { transform: scale(1); }
    50% { transform: scale(1.2); }
    100% { transform: scale(1); }
}

/* ═══════════════════════════════════════════
   LANDING SCREEN
   ═══════════════════════════════════════════ */

.landing-header {
    text-align: center;
    padding: 60px 24px 40px;
}

.logo-mark {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    background: var(--bg-glass);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    margin-bottom: 24px;
    backdrop-filter: blur(20px);
    animation: scaleIn 0.6s ease-out;
}

.logo-icon {
    width: 48px;
    height: 48px;
}

.landing-title {
    font-size: clamp(1.8rem, 4vw, 3rem);
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.03em;
    line-height: 1.2;
    margin-bottom: 12px;
}

.landing-subtitle {
    font-size: 1.05rem;
    color: var(--text-secondary);
    font-weight: 400;
    letter-spacing: 0.01em;
}

/* ── Quiz Selector ── */
.quiz-selector {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px 80px;
}

.selector-section {
    margin-bottom: 48px;
}

.section-heading {
    font-size: 1.35rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 6px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.heading-icon {
    font-size: 1.4rem;
}

.section-desc {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 20px;
    padding-left: 36px;
}

.quiz-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 16px;
}

/* ── Quiz Cards ── */
.quiz-card {
    position: relative;
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 24px;
    cursor: pointer;
    backdrop-filter: blur(12px);
    transition: all var(--transition-normal);
    overflow: hidden;
}

.quiz-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--card-accent, var(--gradient-primary));
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.quiz-card:hover {
    border-color: var(--border-accent);
    background: var(--bg-card-hover);
    transform: translateY(-3px);
    box-shadow: var(--shadow-md), var(--shadow-glow-blue);
}

.quiz-card:hover::before {
    opacity: 1;
}

.quiz-card-icon {
    font-size: 1.8rem;
    margin-bottom: 12px;
    display: block;
}

.quiz-card-title {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 6px;
    line-height: 1.3;
}

.quiz-card-desc {
    font-size: 0.82rem;
    color: var(--text-muted);
    line-height: 1.5;
    margin-bottom: 16px;
}

.quiz-card-meta {
    display: flex;
    align-items: center;
    gap: 16px;
    font-size: 0.78rem;
    color: var(--text-secondary);
}

.quiz-card-meta span {
    display: flex;
    align-items: center;
    gap: 5px;
}

.card-badge {
    display: inline-flex;
    align-items: center;
    padding: 3px 10px;
    border-radius: var(--radius-full);
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.badge-section { background: rgba(66,133,244,0.15); color: var(--accent-blue); }
.badge-mock { background: rgba(251,188,5,0.15); color: var(--accent-yellow); }

/* ═══════════════════════════════════════════
   QUIZ SCREEN
   ═══════════════════════════════════════════ */

.quiz-topbar {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 24px;
    background: rgba(10, 14, 26, 0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-subtle);
}

.btn-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    background: var(--bg-glass);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}
.btn-icon:hover {
    background: var(--bg-glass-hover);
    color: var(--text-primary);
    border-color: var(--border-medium);
}

.quiz-meta {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2px;
}

.quiz-title-text {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-primary);
}

.quiz-progress-text {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.timer-controls {
    display: flex;
    align-items: center;
    gap: 8px;
}

.timer-display {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    background: var(--bg-glass);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--accent-cyan);
    min-width: 120px;
}

.timer-display.paused {
    color: var(--accent-yellow);
    animation: pulse 1.5s ease-in-out infinite;
}

.timer-icon { opacity: 0.7; }

.btn-sm {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    background: var(--bg-glass);
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 0.85rem;
    transition: all var(--transition-fast);
}
.btn-sm:hover {
    background: var(--bg-glass-hover);
    color: var(--text-primary);
}

/* ── Progress Bar ── */
.progress-bar-wrapper {
    position: sticky;
    top: 65px;
    z-index: 99;
    height: 3px;
    background: var(--bg-secondary);
}
.progress-bar {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: 0 3px 3px 0;
    transition: width var(--transition-normal);
    width: 0%;
}

/* ── Quiz Body ── */
.quiz-body {
    max-width: 860px;
    margin: 0 auto;
    padding: 32px 24px 120px;
}

/* ── Question Card ── */
.question-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 32px;
    backdrop-filter: blur(12px);
    animation: slideUp 0.35s ease-out;
}

.question-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.question-number {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-blue);
    background: rgba(66,133,244,0.1);
    padding: 4px 12px;
    border-radius: var(--radius-full);
}

.question-category-badge {
    font-size: 0.72rem;
    font-weight: 500;
    color: var(--text-muted);
    background: var(--bg-glass);
    padding: 4px 12px;
    border-radius: var(--radius-full);
    border: 1px solid var(--border-subtle);
}

.question-text {
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--text-primary);
    margin-bottom: 28px;
    font-weight: 400;
}

/* ── Options ── */
.options-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.option-btn {
    display: flex;
    align-items: flex-start;
    gap: 14px;
    padding: 16px 20px;
    background: var(--bg-glass);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    text-align: left;
    width: 100%;
    font-family: var(--font-body);
    font-size: 0.95rem;
    color: var(--text-primary);
    line-height: 1.5;
}

.option-btn:hover:not(.disabled) {
    background: var(--bg-glass-hover);
    border-color: var(--border-accent);
    transform: translateX(4px);
}

.option-btn.selected {
    background: rgba(66, 133, 244, 0.12);
    border-color: var(--accent-blue);
    box-shadow: var(--shadow-glow-blue);
}

.option-btn.correct {
    background: rgba(52, 168, 83, 0.12);
    border-color: var(--accent-green);
    box-shadow: var(--shadow-glow-green);
}

.option-btn.incorrect {
    background: rgba(234, 67, 53, 0.1);
    border-color: var(--accent-red);
    box-shadow: var(--shadow-glow-red);
}

.option-btn.disabled {
    cursor: default;
    opacity: 0.7;
}

.option-btn.disabled.correct {
    opacity: 1;
}

.option-btn.disabled.incorrect {
    opacity: 1;
}

.option-letter {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 30px;
    height: 30px;
    border-radius: 50%;
    background: var(--bg-glass);
    border: 1px solid var(--border-medium);
    font-weight: 600;
    font-size: 0.82rem;
    color: var(--text-secondary);
    flex-shrink: 0;
    transition: all var(--transition-fast);
}

.option-btn.selected .option-letter {
    background: var(--accent-blue);
    color: white;
    border-color: var(--accent-blue);
}
.option-btn.correct .option-letter {
    background: var(--accent-green);
    color: white;
    border-color: var(--accent-green);
}
.option-btn.incorrect .option-letter {
    background: var(--accent-red);
    color: white;
    border-color: var(--accent-red);
}

.option-text {
    padding-top: 3px;
    flex: 1;
}

/* ── Explanation Panel ── */
.explanation-panel {
    margin-top: 24px;
    padding-top: 24px;
    border-top: 1px solid var(--border-subtle);
    animation: slideUp 0.3s ease-out;
}
.explanation-panel.hidden { display: none; }

.explanation-correct {
    background: rgba(52, 168, 83, 0.08);
    border: 1px solid rgba(52, 168, 83, 0.2);
    border-radius: var(--radius-md);
    padding: 16px 20px;
    margin-bottom: 16px;
    font-size: 0.9rem;
    line-height: 1.7;
    color: var(--text-primary);
}

.explanation-correct::before {
    content: '✅ Correct Answer Explanation';
    display: block;
    font-weight: 700;
    font-size: 0.8rem;
    color: var(--accent-green);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 8px;
}

.explanation-wrong {
    background: rgba(234, 67, 53, 0.05);
    border: 1px solid rgba(234, 67, 53, 0.12);
    border-radius: var(--radius-md);
    padding: 16px 20px;
    font-size: 0.88rem;
    line-height: 1.7;
    color: var(--text-secondary);
}

.explanation-wrong::before {
    content: '❌ Why Other Options Are Incorrect';
    display: block;
    font-weight: 700;
    font-size: 0.8rem;
    color: var(--accent-red);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 8px;
}

.explanation-wrong-item {
    margin-bottom: 10px;
    padding-left: 8px;
    border-left: 2px solid rgba(234, 67, 53, 0.2);
}

.explanation-wrong-item:last-child { margin-bottom: 0; }

.explanation-wrong-item strong {
    color: var(--text-primary);
}

.when-correct {
    display: block;
    margin-top: 4px;
    color: var(--accent-yellow);
    font-style: italic;
    font-size: 0.84rem;
}

/* ── Bottom Bar ── */
.quiz-bottombar {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 24px;
    background: rgba(10, 14, 26, 0.9);
    backdrop-filter: blur(20px);
    border-top: 1px solid var(--border-subtle);
    z-index: 100;
}

.nav-buttons {
    display: flex;
    gap: 10px;
}

/* ── Buttons ── */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: var(--radius-sm);
    font-family: var(--font-body);
    font-size: 0.88rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: 1px solid transparent;
    white-space: nowrap;
}

.btn-primary {
    background: var(--accent-blue);
    color: white;
    border-color: var(--accent-blue);
}
.btn-primary:hover {
    background: #5a9cf5;
    box-shadow: 0 0 20px rgba(66,133,244,0.3);
}

.btn-secondary {
    background: var(--bg-glass);
    color: var(--text-secondary);
    border-color: var(--border-medium);
}
.btn-secondary:hover {
    background: var(--bg-glass-hover);
    color: var(--text-primary);
}

.btn-outline {
    background: transparent;
    color: var(--text-secondary);
    border-color: var(--border-medium);
}
.btn-outline:hover {
    background: var(--bg-glass);
    color: var(--text-primary);
    border-color: var(--border-accent);
}

.btn-accent {
    background: var(--gradient-primary);
    color: white;
    border: none;
}
.btn-accent:hover {
    box-shadow: 0 0 25px rgba(66,133,244,0.35);
    transform: translateY(-1px);
}

.btn:disabled, .btn.disabled {
    opacity: 0.4;
    cursor: not-allowed;
    pointer-events: none;
}

.hidden { display: none !important; }

/* ── Question Navigator ── */
.btn-navigator-toggle {
    position: fixed;
    right: 20px;
    bottom: 80px;
    z-index: 101;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--accent-blue);
    color: white;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md), var(--shadow-glow-blue);
    transition: all var(--transition-fast);
}
.btn-navigator-toggle:hover {
    transform: scale(1.1);
}

.question-navigator {
    position: fixed;
    right: 20px;
    bottom: 140px;
    z-index: 101;
    width: 320px;
    max-height: 420px;
    background: rgba(17, 24, 39, 0.95);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-lg);
    padding: 20px;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    animation: scaleIn 0.2s ease-out;
}

.nav-drawer-title {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.nav-legend {
    display: flex;
    gap: 14px;
    margin-bottom: 14px;
    font-size: 0.72rem;
    color: var(--text-muted);
}

.legend-item { display: flex; align-items: center; gap: 5px; }

.legend-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
}
.legend-dot.answered { background: var(--accent-green); }
.legend-dot.flagged { background: var(--accent-yellow); }
.legend-dot.unanswered { background: var(--bg-glass); border: 1px solid var(--border-medium); }

.nav-grid {
    display: grid;
    grid-template-columns: repeat(8, 1fr);
    gap: 6px;
    margin-bottom: 16px;
}

.nav-cell {
    width: 100%;
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    font-size: 0.7rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    background: var(--bg-glass);
    border: 1px solid var(--border-subtle);
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.nav-cell:hover { border-color: var(--border-accent); }
.nav-cell.current { border-color: var(--accent-blue); background: rgba(66,133,244,0.15); color: var(--accent-blue); }
.nav-cell.answered { background: rgba(52,168,83,0.15); border-color: rgba(52,168,83,0.3); color: var(--accent-green); }
.nav-cell.flagged { background: rgba(251,188,5,0.15); border-color: rgba(251,188,5,0.3); color: var(--accent-yellow); }

.nav-submit-btn {
    width: 100%;
    margin-top: 4px;
}

/* ═══════════════════════════════════════════
   SUBMIT MODAL
   ═══════════════════════════════════════════ */

.modal-overlay {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.65);
    backdrop-filter: blur(4px);
    animation: fadeIn 0.2s ease-out;
}

.modal-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-lg);
    padding: 32px;
    max-width: 440px;
    width: 90%;
    box-shadow: var(--shadow-lg);
    animation: scaleIn 0.25s ease-out;
}

.modal-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.modal-body {
    font-size: 0.92rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 24px;
}

.modal-actions {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
}

/* ═══════════════════════════════════════════
   REPORT SCREEN
   ═══════════════════════════════════════════ */

.report-container {
    max-width: 960px;
    margin: 0 auto;
    padding: 40px 24px 80px;
}

.report-header {
    text-align: center;
    margin-bottom: 40px;
    animation: slideUp 0.5s ease-out;
}

.report-verdict {
    font-size: 1.1rem;
    font-weight: 700;
    padding: 20px 32px;
    border-radius: var(--radius-lg);
    margin-bottom: 20px;
    line-height: 1.5;
}

.verdict-pass {
    background: rgba(52,168,83,0.1);
    border: 1px solid rgba(52,168,83,0.25);
    color: var(--accent-green);
}

.verdict-borderline {
    background: rgba(251,188,5,0.1);
    border: 1px solid rgba(251,188,5,0.25);
    color: var(--accent-yellow);
}

.verdict-fail {
    background: rgba(234,67,53,0.1);
    border: 1px solid rgba(234,67,53,0.2);
    color: var(--accent-red);
}

.report-score-big {
    font-size: 4rem;
    font-weight: 900;
    letter-spacing: -0.04em;
    margin-bottom: 4px;
}

.report-score-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-weight: 500;
}

.report-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 16px;
    margin-bottom: 32px;
}

.report-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 24px;
    backdrop-filter: blur(12px);
    animation: slideUp 0.5s ease-out;
}

.report-card-title {
    font-size: 0.78rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-muted);
    margin-bottom: 16px;
}

.stat-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    border-bottom: 1px solid var(--border-subtle);
    font-size: 0.88rem;
}
.stat-row:last-child { border-bottom: none; }

.stat-label { color: var(--text-secondary); }
.stat-value { font-weight: 600; color: var(--text-primary); font-family: var(--font-mono); }

.stat-value.good { color: var(--accent-green); }
.stat-value.warning { color: var(--accent-yellow); }
.stat-value.danger { color: var(--accent-red); }

/* ── Category Breakdown Bar Chart ── */
.category-bar-container {
    margin-bottom: 14px;
}

.category-bar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 6px;
}

.category-bar-label {
    font-size: 0.82rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.category-bar-percent {
    font-size: 0.8rem;
    font-weight: 600;
    font-family: var(--font-mono);
}

.category-bar-track {
    height: 8px;
    background: var(--bg-glass);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.category-bar-fill {
    height: 100%;
    border-radius: var(--radius-full);
    transition: width 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ── Gap Analysis ── */
.gap-section {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 16px;
    animation: slideUp 0.5s ease-out;
}

.gap-section-title {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.gap-item {
    padding: 12px 16px;
    margin-bottom: 8px;
    border-radius: var(--radius-sm);
    background: var(--bg-glass);
    border-left: 3px solid var(--accent-red);
    font-size: 0.88rem;
    line-height: 1.6;
    color: var(--text-secondary);
}
.gap-item:last-child { margin-bottom: 0; }

.gap-item strong { color: var(--text-primary); }
.gap-item .gap-score {
    font-family: var(--font-mono);
    font-weight: 600;
}

/* ── Report Actions ── */
.report-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    padding-top: 24px;
    flex-wrap: wrap;
}

/* ═══════════════════════════════════════════
   REVIEW SCREEN
   ═══════════════════════════════════════════ */

.review-topbar {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 24px;
    background: rgba(10, 14, 26, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-subtle);
    flex-wrap: wrap;
    gap: 10px;
}

.review-title {
    font-size: 1.05rem;
    font-weight: 700;
}

.review-filter-group {
    display: flex;
    gap: 8px;
    align-items: center;
}

.review-filter {
    width: auto !important;
    height: auto !important;
    min-width: unset !important;
    padding: 6px 16px !important;
    font-size: 0.82rem !important;
    border-radius: var(--radius-full) !important;
    background: var(--bg-glass) !important;
    border: 1px solid var(--border-medium) !important;
    color: var(--text-secondary) !important;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.review-filter:hover {
    background: var(--bg-glass-hover) !important;
    color: var(--text-primary) !important;
    border-color: var(--border-accent) !important;
}

.review-filter.active {
    background: var(--accent-blue) !important;
    color: white !important;
    border-color: var(--accent-blue) !important;
    box-shadow: 0 0 12px rgba(66, 133, 244, 0.3) !important;
}

.review-list {
    max-width: 860px;
    margin: 0 auto;
    padding: 24px 24px 80px;
}

.review-item {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 16px;
    animation: slideUp 0.3s ease-out;
}

.review-item.review-correct {
    border-left: 3px solid var(--accent-green);
}

.review-item.review-incorrect {
    border-left: 3px solid var(--accent-red);
}

.review-q-header {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

.review-q-number {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    font-weight: 600;
    padding: 3px 10px;
    border-radius: var(--radius-full);
}

.review-q-number.rq-correct { background: rgba(52,168,83,0.15); color: var(--accent-green); }
.review-q-number.rq-incorrect { background: rgba(234,67,53,0.15); color: var(--accent-red); }

.review-q-text {
    font-size: 0.95rem;
    line-height: 1.65;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.review-options { display: flex; flex-direction: column; gap: 6px; margin-bottom: 16px; }

.review-opt {
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    font-size: 0.88rem;
    color: var(--text-secondary);
    background: var(--bg-glass);
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.review-opt.ro-correct {
    background: rgba(52,168,83,0.1);
    color: var(--accent-green);
    border: 1px solid rgba(52,168,83,0.2);
}

.review-opt.ro-selected-wrong {
    background: rgba(234,67,53,0.08);
    color: var(--accent-red);
    border: 1px solid rgba(234,67,53,0.15);
    text-decoration: line-through;
    text-decoration-color: rgba(234,67,53,0.4);
}

.review-explanation {
    font-size: 0.85rem;
    line-height: 1.65;
    color: var(--text-muted);
    padding: 14px 16px;
    background: var(--bg-glass);
    border-radius: var(--radius-sm);
    border-left: 2px solid var(--accent-blue);
}

/* ═══════════════════════════════════════════
   SCROLLBAR
   ═══════════════════════════════════════════ */

::-webkit-scrollbar {
    width: 6px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.2);
}

/* ═══════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════ */

@media (max-width: 768px) {
    .quiz-grid {
        grid-template-columns: 1fr;
    }
    .quiz-topbar {
        padding: 10px 14px;
        gap: 8px;
    }
    .quiz-title-text { font-size: 0.75rem; }
    .timer-display { font-size: 0.82rem; min-width: 100px; padding: 5px 10px; }
    .quiz-body { padding: 20px 14px 120px; }
    .question-card { padding: 20px; }
    .question-text { font-size: 0.95rem; }
    .option-btn { padding: 12px 14px; font-size: 0.88rem; }
    .quiz-bottombar { padding: 10px 14px; flex-wrap: wrap; gap: 8px; }
    .nav-buttons { flex-wrap: wrap; }
    .question-navigator { width: 280px; right: 10px; bottom: 120px; }
    .report-grid { grid-template-columns: 1fr; }
    .landing-header { padding: 40px 16px 30px; }
    .review-topbar { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 480px) {
    .quiz-meta { display: none; }
    .btn { padding: 8px 14px; font-size: 0.82rem; }
}
/* Result history entry and result-sync feedback */
.history-link {
    display: inline-flex;
    gap: 8px;
    align-items: center;
    margin-top: 16px;
    color: var(--accent-blue, #8ab4f8);
    font-size: 0.9rem;
    font-weight: 600;
    text-decoration: none;
}

.history-link:hover,
.history-link:focus-visible {
    color: var(--accent-green, #8de68f);
    text-decoration: underline;
    text-underline-offset: 4px;
}

.result-save-status {
    min-height: 1.5em;
    margin: 14px auto 0;
    color: var(--text-secondary, #aeb7c8);
    font-size: 0.88rem;
    text-align: center;
}