:root {
    --bg-primary: #0f172a;
    --bg-card: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --border: #334155;
    --accent: #22c55e;
    --accent-hover: #16a34a;
    --accent-light: #4ade80;
    --success: #22c55e;
    --success-hover: #16a34a;
}

[data-theme="light"] {
    --bg-primary: #f8fafc;
    --bg-card: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --border: #e2e8f0;
    --accent: #16a34a;
    --accent-hover: #15803d;
    --accent-light: #22c55e;
    --success: #16a34a;
    --success-hover: #15803d;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
}

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

.quiz-focus-bg {
    min-height: 100vh;
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 24px;
    width: 100%;
    max-width: 700px;
    margin: 0 auto;
}

.quiz-focus-bg.hidden {
    display: none !important;
}

.quiz-topbar {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 8px 0;
}

.btn-exit {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 22px;
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 6px;
    transition: color 0.2s, background 0.2s;
}

.btn-exit:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
}

.quiz-progress-track {
    flex: 1;
    height: 8px;
    background: var(--border);
    border-radius: 4px;
    overflow: hidden;
}

.quiz-progress-fill {
    height: 100%;
    background: var(--accent);
    width: 10%;
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.quiz-counter {
    font-size: 14px;
    font-weight: 700;
    color: var(--text-secondary);
    min-width: 44px;
    text-align: right;
}

.card-stack {
    position: relative;
    height: 520px;
    max-width: 700px;
    width: 100%;
    margin: 20px auto;
}

.card-stack .quiz-card {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 28px;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    box-shadow: 0 12px 36px rgba(0, 0, 0, 0.3);
    transition: transform 0.2s cubic-bezier(0.2, 0.8, 0.2, 1), opacity 0.2s;
    user-select: none;
    box-sizing: border-box;
    overflow-y: auto;
}

.card-stack .card-stack-0 {
    z-index: 10 !important;
    transform: translateY(0) scale(1) !important;
    opacity: 1 !important;
    pointer-events: auto !important;
    visibility: visible !important;
}

.card-stack .card-stack-1 {
    z-index: 5 !important;
    transform: translateY(14px) scale(0.94) !important;
    opacity: 0.75 !important;
    pointer-events: none !important;
}

.card-stack .card-stack-2 {
    z-index: 2 !important;
    transform: translateY(28px) scale(0.88) !important;
    opacity: 0.45 !important;
    pointer-events: none !important;
}

.card-stack .quiz-card:not(.disabled):hover {
    box-shadow: 0 12px 36px rgba(0, 0, 0, 0.3);
}

.card-stack .card-stack-0:hover {
    transform: translateY(0) scale(1) !important;
}

.card-stack .card-stack-0 .option-item {
    cursor: pointer !important;
    pointer-events: auto !important;
    position: relative;
    z-index: 20;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 18px;
}

.difficulty-tag {
    font-size: 11px;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 4px 12px;
    border-radius: 12px;
}

.difficulty-easy {
    background: #22c55e;
    color: white;
}

.difficulty-medium {
    background: #eab308;
    color: #0f172a;
}

.difficulty-hard {
    background: #ef4444;
    color: white;
}

.btn-card-hint {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 4px 12px;
    border-radius: 14px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-card-hint:hover,
.btn-card-hint.active {
    background: rgba(34, 197, 94, 0.15);
    color: var(--accent);
    border-color: var(--accent);
}

.question-text {
    font-size: 19px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 22px;
    line-height: 1.4;
}

.options-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
    flex: 1;
}

.option-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 18px;
    background: rgba(15, 23, 42, 0.6);
    border: 1.5px solid var(--border);
    border-radius: 14px;
    cursor: pointer;
    font-size: 15px;
    font-weight: 500;
    color: var(--text-primary);
    transition: border-color 0.2s, background 0.2s, transform 0.1s;
}

[data-theme="light"] .option-item {
    background: #f1f5f9;
}

.option-item:hover {
    border-color: var(--accent);
    background: rgba(34, 197, 94, 0.08);
}

.option-item.selected {
    border-color: var(--accent);
    background: rgba(34, 197, 94, 0.18);
    font-weight: 600;
}

.option-radio {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    border: 2px solid var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: border-color 0.2s, background 0.2s;
}

.option-item.selected .option-radio {
    border-color: var(--accent);
    background: var(--accent);
    box-shadow: 0 0 8px rgba(34, 197, 94, 0.5);
}

.option-item.selected .option-radio::after {
    content: '';
    width: 6px;
    height: 6px;
    background: white;
    border-radius: 50%;
}

.in-card-hint {
    margin-top: 14px;
    padding: 12px 16px;
    background: rgba(34, 197, 94, 0.12);
    border: 1px solid rgba(34, 197, 94, 0.25);
    border-radius: 12px;
    font-size: 14px;
    color: var(--text-primary);
}

.in-card-hint.hidden {
    display: none;
}

.quiz-controls {
    display: flex;
    gap: 14px;
    margin-top: 16px;
}

.btn-nav {
    flex: 1;
    padding: 14px 20px;
    border-radius: 14px;
    border: 1px solid var(--border);
    background: var(--bg-card);
    color: var(--text-primary);
    font-size: 15px;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.15s, background 0.2s, border-color 0.2s;
}

.btn-nav:hover:not(:disabled) {
    border-color: var(--accent);
    transform: translateY(-1px);
}

.btn-nav:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.btn-next {
    background: var(--accent);
    color: white;
    border: none;
}

.btn-next:hover:not(:disabled) {
    background: var(--accent-hover);
}

.btn-finish {
    background: var(--success);
    color: white;
    border: none;
}

.btn-finish:hover:not(:disabled) {
    background: var(--success-hover);
}

.btn-nav.hidden {
    display: none !important;
}

/* Modal Overlay & Centered Dialog Box */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(8px);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 500;
    padding: 20px;
}

.modal-overlay:not(.hidden) {
    display: flex;
}

.modal-overlay.hidden {
    display: none !important;
}

.modal-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 32px 28px;
    text-align: center;
    max-width: 420px;
    width: 90%;
    box-shadow: 0 24px 60px rgba(0, 0, 0, 0.5);
}

.modal-icon {
    font-size: 44px;
    margin-bottom: 12px;
}

.modal-card h3 {
    font-size: 22px;
    font-weight: 800;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.modal-card p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
    margin-bottom: 24px;
}

.input-group {
    margin-bottom: 24px;
}

.input-group input,
.form-field input,
.form-field select {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 15px;
}

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

.btn-modal {
    flex: 1;
    padding: 12px 16px;
    border-radius: 12px;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.15s, background 0.2s;
}

.btn-cancel {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
}

.btn-cancel:hover {
    color: var(--text-primary);
    border-color: var(--text-secondary);
}

.btn-confirm {
    background: var(--accent);
    border: none;
    color: white;
}

.btn-confirm:hover {
    background: var(--accent-hover);
}

/* Share Achievement Menu Overlay & Centered Dialog */
.share-menu-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.75);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 500;
    padding: 20px;
}

.share-menu-box {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 32px 24px;
    text-align: center;
    max-width: 420px;
    width: 90%;
    box-shadow: 0 24px 60px rgba(0, 0, 0, 0.5);
}

.share-menu-box h3 {
    font-size: 20px;
    font-weight: 800;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.share-options {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
    margin-bottom: 20px;
}

.share-opt {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 16px;
    border-radius: 12px;
    border: 1px solid var(--border);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: transform 0.15s, border-color 0.2s, background 0.2s, box-shadow 0.2s, color 0.2s;
}

.share-opt:hover {
    border-color: var(--accent);
    background: rgba(34, 197, 94, 0.15);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(34, 197, 94, 0.2);
}

.share-opt i {
    font-size: 16px;
}

.share-opt-linkedin i {
    color: #0a66c2;
}

.share-opt-x i {
    color: var(--text-primary);
}

.share-opt-native i {
    color: var(--accent);
}

.share-opt-copy i {
    color: var(--success);
}

.share-close {
    width: 100%;
    padding: 12px;
    border-radius: 12px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: color 0.2s, border-color 0.2s, background 0.2s;
}

.share-close:hover {
    color: var(--text-primary);
    border-color: var(--text-secondary);
    background: rgba(255, 255, 255, 0.05);
}

/* Light Mode Styling for Share Modal */
[data-theme="light"] .share-menu-overlay {
    background: rgba(15, 23, 42, 0.45);
}

[data-theme="light"] .share-menu-box {
    background: #ffffff;
    border: 1px solid #e2e8f0;
    box-shadow: 0 20px 40px rgba(15, 23, 42, 0.12);
}

[data-theme="light"] .share-opt {
    background: #ffffff;
    border: 1px solid #e2e8f0;
    color: #0f172a;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

[data-theme="light"] .share-opt:hover {
    border-color: var(--accent);
    background: rgba(22, 163, 74, 0.08);
    color: var(--accent);
    box-shadow: 0 4px 14px rgba(22, 163, 74, 0.18);
}

[data-theme="light"] .share-opt-x i {
    color: #0f172a;
}

[data-theme="light"] .share-close {
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    color: #64748b;
}

[data-theme="light"] .share-close:hover {
    background: #f1f5f9;
    color: #0f172a;
    border-color: #cbd5e1;
}

/* Tinder Swipe Badges */
.swipe-badge {
    position: absolute;
    top: 20px;
    padding: 6px 16px;
    border-radius: 8px;
    font-weight: 800;
    font-size: 14px;
    opacity: 0;
    transition: opacity 0.1s;
    pointer-events: none;
}

.badge-next {
    right: 20px;
    border: 2px solid var(--accent);
    color: var(--accent);
    transform: rotate(12deg);
}

.badge-prev {
    left: 20px;
    border: 2px solid var(--text-secondary);
    color: var(--text-secondary);
    transform: rotate(-12deg);
}

/* Results Screen */
.results-screen {
    min-height: 100vh;
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 32px 24px;
    text-align: center;
    width: 100%;
    max-width: 700px;
    margin: 0 auto;
}

.results-screen.hidden {
    display: none !important;
}

.results-icon {
    font-size: 64px;
    margin-bottom: 16px;
    cursor: pointer;
}

.results-title {
    font-size: 28px;
    font-weight: 800;
    margin-bottom: 8px;
}

.results-score {
    font-size: 20px;
    color: var(--accent);
    font-weight: 700;
    margin-bottom: 24px;
}

.results-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 20px;
    margin-bottom: 24px;
    width: 100%;
}

.btn-result-action {
    width: 100%;
    padding: 14px;
    border-radius: 12px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    margin-bottom: 10px;
}

.btn-primary-result {
    background: var(--accent);
    color: white;
    border: none;
}

.btn-secondary-result {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-primary);
}

/* Guest Warning Banner on Results Screen */
.guest-warning-card {
    background: rgba(245, 158, 11, 0.1);
    border: 1px solid rgba(245, 158, 11, 0.35);
    border-radius: 14px;
    padding: 16px 18px;
    margin-bottom: 20px;
    text-align: left;
    display: flex;
    gap: 12px;
    align-items: flex-start;
    color: var(--text-primary);
    font-size: 13.5px;
    line-height: 1.55;
    box-shadow: 0 4px 16px rgba(245, 158, 11, 0.08);
    width: 100%;
}

.guest-warning-icon {
    font-size: 20px;
    flex-shrink: 0;
    margin-top: 1px;
}

[data-theme="light"] .guest-warning-card {
    background: rgba(217, 119, 6, 0.08);
    border-color: rgba(217, 119, 6, 0.3);
    color: #451a03;
}

.btn-signin-result {
    background: linear-gradient(135deg, #22c55e, #16a34a);
    color: white;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.btn-signin-result:hover {
    opacity: 0.95;
    transform: translateY(-1px);
}

/* Dual Party Popper Confetti Animation (Bottom-Left & Bottom-Right Cannons) */
.confetti-piece {
    position: fixed;
    bottom: -10px;
    z-index: 999;
    pointer-events: none;
    will-change: transform, opacity;
}

.popper-left {
    left: 8%;
    animation: partyPopperBurstLeft 3.4s cubic-bezier(0.15, 0.85, 0.35, 1) forwards;
}

.popper-right {
    right: 8%;
    animation: partyPopperBurstRight 3.4s cubic-bezier(0.15, 0.85, 0.35, 1) forwards;
}

@keyframes partyPopperBurstLeft {
    0% {
        transform: translate(0, 0) rotate(0deg) scale(0.5);
        opacity: 1;
    }
    38% {
        /* Shoot up & right towards top-center */
        transform: translate(var(--tx, 30vw), var(--ty, -68vh)) rotate(var(--rot, 360deg)) scale(1.25);
        opacity: 1;
    }
    100% {
        /* Flutter and drift down across center screen */
        transform: translate(var(--fall-x, 35vw), 15vh) rotate(calc(var(--rot, 360deg) * 2.5)) scale(0.6);
        opacity: 0;
    }
}

@keyframes partyPopperBurstRight {
    0% {
        transform: translate(0, 0) rotate(0deg) scale(0.5);
        opacity: 1;
    }
    38% {
        /* Shoot up & left towards top-center */
        transform: translate(var(--tx, -30vw), var(--ty, -68vh)) rotate(var(--rot, -360deg)) scale(1.25);
        opacity: 1;
    }
    100% {
        /* Flutter and drift down across center screen */
        transform: translate(var(--fall-x, -35vw), 15vh) rotate(calc(var(--rot, -360deg) * 2.5)) scale(0.6);
        opacity: 0;
    }
}

/* Cookie Consent Sticky Bottom Banner */
.cookie-banner {
    position: fixed;
    bottom: 24px;
    left: 24px;
    right: 24px;
    max-width: 520px;
    margin: 0 auto;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 18px;
    padding: 18px 22px;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4);
    z-index: 999;
}

.cookie-banner.hidden {
    display: none !important;
}

.cookie-content {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.cookie-content p {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.5;
}

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

.btn-cookie {
    padding: 8px 18px;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-reject {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
}

.btn-reject:hover {
    color: var(--text-primary);
    border-color: var(--text-secondary);
}

.btn-standard {
    background: var(--accent);
    border: none;
    color: white;
}

.btn-standard:hover {
    background: var(--accent-hover);
}

/* Toast Notification */
.cert-toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--success);
    color: white;
    padding: 14px 24px;
    border-radius: 12px;
    font-weight: 700;
    font-size: 15px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.3);
    z-index: 10000;
    opacity: 0;
    transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275), opacity 0.4s ease;
    pointer-events: none;
    text-align: center;
    width: max-content;
    max-width: 90%;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.cert-toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

.cert-toast.toast-error {
    background: #ef4444;
}

.cert-toast.toast-info {
    background: #3b82f6;
}

.cert-toast.toast-success {
    background: var(--success);
}

.btn-danger-modal {
    background: #dc2626 !important;
    color: white !important;
}

.btn-danger-modal:hover {
    background: #b91c1c !important;
}

/* Results Summary */
.results-summary-list {
    margin-top: 16px;
    text-align: left;
    max-height: 40vh;
    overflow-y: auto;
    width: 100%;
    padding-right: 8px;
}

.summary-item {
    background: rgba(15, 23, 42, 0.4);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 12px 16px;
    margin-bottom: 10px;
    font-size: 13px;
}

[data-theme="light"] .summary-item {
    background: rgba(241, 245, 249, 0.6);
}

.summary-item.correct {
    border-left: 4px solid var(--success);
}

.summary-item.incorrect {
    border-left: 4px solid #ef4444;
}

.summary-q {
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.summary-a {
    color: var(--text-secondary);
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.summary-a .correct-text { color: var(--success); font-weight: 600; }
.summary-a .wrong-text { color: #ef4444; font-weight: 600; }