/* Quiz Practice */
.quiz-shell {
    width: min(100%, 920px);
    margin: 0 auto;
    display: grid;
    gap: 18px;
    animation: fadeIn 0.3s ease;
}

.quiz-gate,
.quiz-card,
.quiz-status-card,
.quiz-sync-panel {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    box-shadow: var(--shadow-card);
}

.quiz-gate {
    width: min(100%, 540px);
    margin: clamp(24px, 8vh, 84px) auto 0;
    padding: clamp(26px, 5vw, 42px);
    border-radius: var(--radius-xl);
    text-align: center;
}

.quiz-gate-mark {
    width: 72px;
    height: 72px;
    margin: 0 auto 20px;
    display: grid;
    place-items: center;
    color: #fff;
    border-radius: 22px;
    background: var(--gradient-1);
    box-shadow: 0 16px 34px rgba(59, 109, 230, 0.22);
}

.quiz-gate-mark svg {
    width: 34px;
    height: 34px;
}

.quiz-eyebrow {
    color: var(--accent-blue);
    font-size: 0.75rem;
    font-weight: 800;
    letter-spacing: 0.11em;
    text-transform: uppercase;
}

.quiz-gate h2 {
    margin-top: 8px;
    font-size: clamp(1.65rem, 5vw, 2.25rem);
    line-height: 1.15;
}

.quiz-gate-copy {
    max-width: 410px;
    margin: 12px auto 24px;
    color: var(--text-secondary);
    font-size: 0.96rem;
    line-height: 1.65;
}

.quiz-password-form {
    display: grid;
    gap: 12px;
}

.quiz-input,
.quiz-textarea,
.quiz-select {
    width: 100%;
    min-height: 48px;
    color: var(--text-primary);
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    font: inherit;
    font-size: 16px;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.quiz-input {
    padding: 0 15px;
}

.quiz-textarea {
    min-height: 132px;
    padding: 14px 15px;
    line-height: 1.55;
    resize: vertical;
}

.quiz-select {
    padding: 0 38px 0 12px;
}

.quiz-input:focus,
.quiz-textarea:focus,
.quiz-select:focus {
    outline: none;
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 3px var(--border-active);
}

.quiz-form-error {
    min-height: 20px;
    color: var(--accent-rose);
    font-size: 0.85rem;
    font-weight: 650;
}

.quiz-btn {
    min-height: 46px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 0 17px;
    color: var(--text-primary);
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    font: inherit;
    font-size: 0.9rem;
    font-weight: 750;
    line-height: 1.2;
    cursor: pointer;
    touch-action: manipulation;
    transition: transform var(--transition-fast), background var(--transition-fast), border-color var(--transition-fast), filter var(--transition-fast);
}

.quiz-btn:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-active);
}

.quiz-btn:active {
    transform: scale(0.98);
}

.quiz-btn:disabled {
    opacity: 0.45;
    cursor: default;
    transform: none;
}

.quiz-btn-primary {
    color: #fff;
    background: var(--gradient-1);
    border-color: transparent;
}

.quiz-btn-primary:hover {
    background: var(--gradient-1);
    border-color: transparent;
    filter: brightness(1.06);
}

.quiz-btn-success {
    color: #fff;
    background: var(--accent-emerald);
    border-color: transparent;
}

.quiz-btn-danger {
    color: var(--accent-rose);
}

.quiz-btn svg {
    width: 18px;
    height: 18px;
    flex: 0 0 auto;
}

.quiz-topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
}

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

.quiz-title-wrap {
    min-width: 0;
}

.quiz-page-title {
    margin-top: 3px;
    font-size: clamp(1.35rem, 4vw, 1.85rem);
    line-height: 1.18;
}

.quiz-sync-button {
    flex: 0 0 auto;
}

.quiz-focus-button {
    flex: 0 0 auto;
}

.quiz-focus-button.is-active {
    color: var(--accent-blue);
    background: color-mix(in srgb, var(--accent-blue) 9%, var(--bg-card));
    border-color: var(--border-active);
}

.quiz-sync-dot {
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--text-muted);
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--text-muted) 15%, transparent);
}

.quiz-sync-dot.is-synced {
    background: var(--accent-emerald);
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent-emerald) 16%, transparent);
}

.quiz-sync-dot.is-saving,
.quiz-sync-dot.is-connecting {
    background: var(--accent-amber);
    animation: quizPulse 1s ease-in-out infinite;
}

.quiz-sync-dot.is-error,
.quiz-sync-dot.is-offline {
    background: var(--accent-rose);
}

@keyframes quizPulse {
    50% { opacity: 0.45; transform: scale(0.8); }
}

.quiz-status-card {
    padding: 16px 18px 17px;
    border-radius: var(--radius-md);
}

.quiz-status-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 11px;
    color: var(--text-secondary);
    font-size: 0.82rem;
    font-weight: 700;
}

.quiz-progress-track {
    height: 7px;
    overflow: hidden;
    background: var(--bg-surface);
    border-radius: 999px;
}

.quiz-progress-fill {
    width: var(--quiz-progress, 0%);
    height: 100%;
    background: var(--gradient-1);
    border-radius: inherit;
    transition: width var(--transition-med);
}

.quiz-stats {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 9px;
    margin-top: 13px;
}

.quiz-stat {
    min-width: 0;
    padding: 10px 12px;
    background: var(--bg-surface);
    border-radius: var(--radius-sm);
}

.quiz-stat-value {
    display: block;
    color: var(--text-primary);
    font-size: 1.05rem;
    font-weight: 800;
    font-variant-numeric: tabular-nums;
}

.quiz-stat-label {
    display: block;
    margin-top: 2px;
    color: var(--text-muted);
    font-size: 0.69rem;
    font-weight: 700;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.quiz-card {
    padding: clamp(20px, 4vw, 34px);
    border-radius: var(--radius-xl);
}

.quiz-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 7px;
    margin-bottom: 19px;
}

.quiz-pill {
    display: inline-flex;
    align-items: center;
    min-height: 28px;
    padding: 4px 9px;
    color: var(--text-secondary);
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: 999px;
    font-size: 0.72rem;
    font-weight: 750;
    line-height: 1.25;
}

.quiz-pill-topic {
    color: var(--accent-blue);
    background: color-mix(in srgb, var(--accent-blue) 8%, var(--bg-card));
    border-color: color-mix(in srgb, var(--accent-blue) 18%, transparent);
}

.quiz-vignette {
    margin-bottom: 22px;
    overflow: hidden;
    background: color-mix(in srgb, var(--accent-purple) 6%, var(--bg-card));
    border: 1px solid color-mix(in srgb, var(--accent-purple) 18%, transparent);
    border-radius: var(--radius-md);
}

.quiz-vignette summary {
    min-height: 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding: 11px 14px;
    color: var(--accent-purple);
    font-size: 0.82rem;
    font-weight: 800;
    cursor: pointer;
    list-style: none;
}

.quiz-vignette summary::-webkit-details-marker {
    display: none;
}

.quiz-vignette summary::after {
    content: "›";
    font-size: 1.35rem;
    transform: rotate(90deg);
    transition: transform var(--transition-fast);
}

.quiz-vignette:not([open]) summary::after {
    transform: rotate(0deg);
}

.quiz-vignette-body {
    padding: 0 15px 16px;
    border-top: 1px solid color-mix(in srgb, var(--accent-purple) 14%, transparent);
}

.quiz-question-label {
    margin-bottom: 10px;
    color: var(--text-muted);
    font-size: 0.75rem;
    font-weight: 800;
    letter-spacing: 0.07em;
    text-transform: uppercase;
}

.quiz-prompt {
    margin-bottom: 24px;
    color: var(--text-primary);
    font-size: clamp(1.04rem, 2.7vw, 1.2rem);
    font-weight: 570;
    line-height: 1.72;
}

.quiz-prompt:focus {
    outline: none;
}

.quiz-rich-text {
    white-space: pre-wrap;
    overflow-wrap: anywhere;
    word-break: normal;
    font-variant-numeric: tabular-nums;
}

.quiz-formula-text {
    font-family: "Cambria Math", Cambria, "Times New Roman", serif;
    letter-spacing: 0.01em;
}

/* Tables reconstructed from flattened source text. */
.quiz-table-wrap {
    margin: 14px 0;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
}

.quiz-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
    font-weight: 400;
    line-height: 1.4;
    font-variant-numeric: tabular-nums;
    white-space: nowrap;
}

.quiz-table th,
.quiz-table td {
    padding: 8px 14px;
    border-bottom: 1px solid var(--border-subtle);
    text-align: left;
}

.quiz-table tbody tr:last-child td {
    border-bottom: 0;
}

.quiz-table thead th {
    font-weight: 700;
    color: var(--text-secondary);
    background: var(--bg-secondary);
    border-bottom: 2px solid var(--border-active);
}

.quiz-table .quiz-th-caption {
    white-space: normal;
    font-weight: 700;
}

.quiz-table .quiz-th-num,
.quiz-table .quiz-td-num {
    text-align: right;
    font-variant-numeric: tabular-nums;
}

.quiz-table .quiz-td-label {
    color: var(--text-secondary);
}

.quiz-choices {
    display: grid;
    gap: 10px;
    margin: 0;
    padding: 0;
    border: 0;
}

.quiz-choices legend {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
}

.quiz-choice {
    position: relative;
    min-height: 52px;
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    cursor: pointer;
    touch-action: manipulation;
    transition: background var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast);
}

.quiz-choice:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-active);
}

.quiz-choice:active {
    transform: scale(0.992);
}

/* Native radio is visually hidden but kept fully functional and focusable;
   the circular marker below is the visible control with the letter inside it. */
.quiz-choice-input {
    position: absolute;
    width: 1px;
    height: 1px;
    margin: 0;
    padding: 0;
    opacity: 0;
    pointer-events: none;
}

.quiz-choice-marker {
    flex: none;
    width: 26px;
    height: 26px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    border: 2px solid var(--border-active);
    background: var(--bg-card);
    color: var(--text-muted);
    font-size: 0.72rem;
    font-weight: 800;
    line-height: 1;
    letter-spacing: 0;
    transition: background var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast);
}

.quiz-choice-input:checked + .quiz-choice-marker {
    background: var(--accent-blue);
    border-color: var(--accent-blue);
    color: #fff;
}

.quiz-choice-content {
    min-width: 0;
    color: var(--text-primary);
    font-size: 0.95rem;
    line-height: 1.55;
}

.quiz-choice.is-correct {
    background: color-mix(in srgb, var(--accent-emerald) 9%, var(--bg-card));
    border-color: color-mix(in srgb, var(--accent-emerald) 58%, transparent);
}

.quiz-choice.is-correct .quiz-choice-marker {
    background: var(--accent-emerald);
    border-color: var(--accent-emerald);
    color: #fff;
}

.quiz-choice.is-wrong {
    background: color-mix(in srgb, var(--accent-rose) 8%, var(--bg-card));
    border-color: color-mix(in srgb, var(--accent-rose) 58%, transparent);
}

.quiz-choice.is-wrong .quiz-choice-marker {
    background: var(--accent-rose);
    border-color: var(--accent-rose);
    color: #fff;
}

.quiz-choice.is-answered {
    cursor: default;
}

.quiz-choice.is-answered:active {
    transform: none;
}

.quiz-feedback {
    margin-top: 18px;
    padding: 17px 18px;
    border: 1px solid var(--border-subtle);
    border-left-width: 4px;
    border-radius: var(--radius-md);
    scroll-margin-top: 130px;
}

.quiz-feedback.is-correct {
    background: color-mix(in srgb, var(--accent-emerald) 7%, var(--bg-card));
    border-left-color: var(--accent-emerald);
}

.quiz-feedback.is-wrong {
    background: color-mix(in srgb, var(--accent-rose) 6%, var(--bg-card));
    border-left-color: var(--accent-rose);
}

.quiz-feedback-title {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 8px;
    font-size: 0.95rem;
    font-weight: 850;
}

.quiz-feedback.is-correct .quiz-feedback-title {
    color: var(--accent-emerald);
}

.quiz-feedback.is-wrong .quiz-feedback-title {
    color: var(--accent-rose);
}

.quiz-feedback-copy {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.65;
}

.quiz-correct-answer {
    margin-bottom: 10px;
    color: var(--text-primary);
    font-weight: 750;
}

.quiz-written {
    display: grid;
    gap: 13px;
}

.quiz-written-help {
    color: var(--text-muted);
    font-size: 0.82rem;
    line-height: 1.5;
}

.quiz-model-answer {
    margin-top: 16px;
    padding: 18px;
    background: color-mix(in srgb, var(--accent-blue) 5%, var(--bg-card));
    border: 1px solid color-mix(in srgb, var(--accent-blue) 18%, transparent);
    border-radius: var(--radius-md);
}

.quiz-model-answer h3 {
    margin-bottom: 10px;
    color: var(--accent-blue);
    font-size: 0.88rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.quiz-self-grade {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 14px;
}

.quiz-matching {
    display: grid;
    gap: 11px;
}

.quiz-match-row {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 28px minmax(0, 1fr);
    align-items: center;
    gap: 10px;
    padding: 13px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
}

.quiz-match-left {
    min-width: 0;
    color: var(--text-primary);
    font-size: 0.9rem;
    font-weight: 650;
    line-height: 1.45;
}

.quiz-match-arrow {
    color: var(--text-muted);
    text-align: center;
}

.quiz-actions {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.quiz-actions-right {
    display: flex;
    align-items: center;
    gap: 10px;
}

.quiz-sync-panel {
    padding: clamp(19px, 4vw, 27px);
    border-radius: var(--radius-lg);
}

.quiz-sync-panel[hidden] {
    display: none;
}

.quiz-sync-head {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 12px;
}

.quiz-sync-head h3 {
    font-size: 1.05rem;
}

.quiz-sync-copy {
    margin-top: 6px;
    color: var(--text-secondary);
    font-size: 0.86rem;
    line-height: 1.55;
}

.quiz-token-form {
    display: grid;
    gap: 11px;
    margin-top: 17px;
}

.quiz-token-link {
    color: var(--accent-blue);
    font-size: 0.84rem;
    font-weight: 750;
    text-underline-offset: 3px;
}

.quiz-sync-account {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-top: 17px;
    padding: 14px;
    background: var(--bg-surface);
    border-radius: var(--radius-sm);
}

.quiz-sync-account strong,
.quiz-sync-account span {
    display: block;
}

.quiz-sync-account span {
    margin-top: 3px;
    color: var(--text-muted);
    font-size: 0.78rem;
}

.quiz-sync-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 9px;
    margin-top: 14px;
}

.quiz-sync-message {
    min-height: 20px;
    margin-top: 12px;
    color: var(--text-secondary);
    font-size: 0.8rem;
    line-height: 1.45;
}

.quiz-sync-message.is-error {
    color: var(--accent-rose);
    font-weight: 650;
}

.quiz-empty,
.quiz-loading {
    min-height: 280px;
    display: grid;
    place-items: center;
    padding: 32px;
    color: var(--text-secondary);
    text-align: center;
}

.quiz-loading-inner {
    display: grid;
    justify-items: center;
    gap: 14px;
}

.quiz-spinner {
    width: 34px;
    height: 34px;
    border: 3px solid var(--border-subtle);
    border-top-color: var(--accent-blue);
    border-radius: 50%;
    animation: quizSpin 0.75s linear infinite;
}

@keyframes quizSpin {
    to { transform: rotate(360deg); }
}

.quiz-complete {
    padding: clamp(28px, 7vw, 52px);
    text-align: center;
}

.quiz-complete-icon {
    width: 68px;
    height: 68px;
    display: grid;
    place-items: center;
    margin: 0 auto 18px;
    color: #fff;
    background: var(--gradient-2);
    border-radius: 50%;
    font-size: 1.8rem;
}

.quiz-complete h2 {
    font-size: clamp(1.55rem, 5vw, 2.1rem);
}

.quiz-complete p {
    margin: 10px auto 22px;
    color: var(--text-secondary);
    line-height: 1.6;
}

.quiz-btn:focus-visible,
.quiz-choice:has(input:focus-visible),
.quiz-vignette summary:focus-visible,
.quiz-token-link:focus-visible {
    outline: 3px solid var(--accent-blue);
    outline-offset: 3px;
}

html.quiz-focus-mode .header,
html.quiz-focus-mode .content-tabs,
html.quiz-focus-mode #searchSection,
html.quiz-focus-mode #cheatSheetPicker {
    display: none !important;
}

html.quiz-focus-mode .page-watermark,
html.quiz-focus-mode .app-container::after {
    display: none !important;
}

html.quiz-focus-mode .app-container {
    max-width: 1100px;
    padding-top: max(14px, env(safe-area-inset-top)) !important;
    padding-bottom: calc(28px + env(safe-area-inset-bottom)) !important;
}

@media (max-width: 720px) {
    .quiz-shell {
        gap: 14px;
    }

    .quiz-gate {
        margin-top: 18px;
    }

    .quiz-topbar {
        align-items: flex-start;
    }

    .quiz-sync-button {
        min-height: 46px;
        padding: 0 12px;
    }

    .quiz-focus-button {
        min-width: 46px;
        min-height: 46px;
        padding: 0 12px;
    }

    .quiz-status-card {
        padding: 14px;
    }

    .quiz-stat {
        padding: 9px 8px;
    }

    .quiz-stat-value {
        font-size: 0.95rem;
    }

    .quiz-card {
        border-radius: var(--radius-lg);
    }

    .quiz-choice {
        padding: 12px 13px;
    }

    .quiz-match-row {
        grid-template-columns: 1fr;
        gap: 8px;
    }

    .quiz-match-arrow {
        display: none;
    }

    .quiz-actions {
        align-items: stretch;
    }

    .quiz-actions-right {
        flex: 1;
    }

    .quiz-actions-right .quiz-btn {
        flex: 1;
    }

    .quiz-sync-account {
        align-items: flex-start;
        flex-direction: column;
    }
}

@media (max-width: 430px) {
    .quiz-focus-label {
        position: absolute;
        width: 1px;
        height: 1px;
        overflow: hidden;
        clip: rect(0, 0, 0, 0);
        white-space: nowrap;
    }

    .quiz-btn {
        padding-right: 13px;
        padding-left: 13px;
    }

    .quiz-actions {
        display: flex;
    }

    .quiz-actions > .quiz-btn,
    .quiz-actions-right {
        width: auto;
        flex: 1 1 0;
    }

    .quiz-actions-right .quiz-btn {
        width: 100%;
    }

    .quiz-self-grade .quiz-btn,
    .quiz-sync-actions .quiz-btn {
        width: 100%;
    }
}

@media (prefers-reduced-motion: reduce) {
    .quiz-shell,
    .quiz-spinner,
    .quiz-sync-dot,
    .quiz-progress-fill {
        animation: none !important;
        transition: none !important;
    }
}