:root {
    --bg-page: #f8fafc;
    --bg-card: #ffffff;
    --border-color: #e2e8f0;
    --border-focus: #2563eb;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --text-sub: #475569;
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --primary-light: #eff6ff;
    --success: #16a34a;
    --success-light: #f0fdf4;
    --danger: #dc2626;
    --danger-light: #fef2f2;
    --warning: #d97706;
    --warning-light: #fffbeb;
    --radius-sharp: 4px;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    -webkit-tap-highlight-color: transparent;
}

body.light-mode {
    background-color: var(--bg-page);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
}

.reading-app {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

                                                            
                                                    
                                                               
.reading-top-bar {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: #ffffff;
    border-bottom: 1px solid var(--border-color);
    height: 60px;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    box-shadow: var(--shadow-sm);
}

.bar-left {
    display: flex;
    align-items: center;
    gap: 14px;
    flex-shrink: 0;
}

.nav-back-pill {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 14px;
    background-color: #f1f5f9;
    color: var(--text-main);
    text-decoration: none;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: var(--radius-sharp);
    border: 1px solid #cbd5e1;
    transition: all 0.15s ease;
}

.nav-back-pill:hover {
    background-color: #e2e8f0;
    color: var(--primary);
}

.brand-divider {
    width: 1px;
    height: 24px;
    background-color: var(--border-color);
}

.exam-tag {
    font-size: 0.88rem;
    font-weight: 700;
    color: var(--text-main);
    background-color: var(--primary-light);
    color: var(--primary);
    padding: 4px 10px;
    border-radius: var(--radius-sharp);
    border: 1px solid #bfdbfe;
    letter-spacing: 0.3px;
}

.bar-center {
    flex: 1;
    max-width: 440px;
    display: flex;
    justify-content: center;
}

.test-switcher-wrap {
    position: relative;
    width: 100%;
    display: flex;
    align-items: center;
}

.switcher-icon {
    position: absolute;
    left: 12px;
    color: var(--text-muted);
    font-size: 0.85rem;
    pointer-events: none;
}

.test-select-dropdown {
    width: 100%;
    height: 38px;
    padding: 0 12px 0 34px;
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    font-size: 0.86rem;
    font-weight: 600;
    color: var(--text-main);
    cursor: pointer;
    outline: none;
    transition: border-color 0.15s;
}

.test-select-dropdown:focus {
    border-color: var(--primary);
}

.bar-right {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

.hud-pill {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background-color: #f8fafc;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--text-main);
}

.timer-pill {
    color: var(--text-main);
    font-family: monospace;
    font-size: 0.95rem;
}

.timer-pill.warning {
    color: var(--warning);
    background-color: var(--warning-light);
    border-color: #fde68a;
}

.timer-pill.danger {
    color: var(--danger);
    background-color: var(--danger-light);
    border-color: #fecaca;
    animation: pulseDanger 1.2s infinite;
}

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

.progress-pill {
    color: var(--primary);
    background-color: var(--primary-light);
    border-color: #bfdbfe;
}

                                                            
                            
                                                               
.reading-container {
    flex: 1;
    max-width: 1380px;
    width: 100%;
    margin: 0 auto;
    padding: 24px 20px 80px 20px;
}

.reading-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    box-shadow: var(--shadow-sm);
    padding: 28px 32px;
}

            
.reading-card-header {
    margin-bottom: 24px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.header-tags {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 12px;
}

.badge-level {
    padding: 4px 8px;
    background-color: #f1f5f9;
    color: var(--primary);
    font-size: 0.78rem;
    font-weight: 800;
    border-radius: var(--radius-sharp);
    border: 1px solid #cbd5e1;
    text-transform: uppercase;
}

.badge-type {
    padding: 4px 8px;
    background-color: #f8fafc;
    color: var(--text-sub);
    font-size: 0.78rem;
    font-weight: 600;
    border-radius: var(--radius-sharp);
    border: 1px solid var(--border-color);
}

.badge-time {
    padding: 4px 8px;
    background-color: #f8fafc;
    color: var(--text-muted);
    font-size: 0.78rem;
    font-weight: 600;
    border-radius: var(--radius-sharp);
}

.passage-title {
    font-size: 1.45rem;
    font-weight: 800;
    color: var(--text-main);
    line-height: 1.35;
    margin-bottom: 12px;
}

.instructions-banner {
    background-color: #f8fafc;
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--primary);
    border-radius: var(--radius-sharp);
    padding: 12px 16px;
    font-size: 0.88rem;
    color: var(--text-sub);
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.instruction-row {
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.inst-pill {
    display: inline-block;
    padding: 2px 7px;
    background-color: #ffffff;
    border: 1px solid #cbd5e1;
    border-radius: var(--radius-sharp);
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--primary);
    flex-shrink: 0;
}

                                              
.mobile-segmented-bar {
    display: none;
    margin-top: 16px;
    background-color: #f1f5f9;
    padding: 4px;
    border-radius: var(--radius-sharp);
    gap: 4px;
}

.segmented-tab {
    flex: 1;
    padding: 10px 14px;
    border: none;
    background: transparent;
    border-radius: var(--radius-sharp);
    font-size: 0.86rem;
    font-weight: 700;
    color: var(--text-muted);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all 0.15s ease;
}

.segmented-tab.active {
    background-color: #ffffff;
    color: var(--primary);
    box-shadow: var(--shadow-sm);
}

                                                            
                              
                                                               
.part4-workspace {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 28px;
    align-items: start;
}

.pane-passage,
.pane-questions {
    background-color: #ffffff;
}

.pane-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-bottom: 12px;
    margin-bottom: 16px;
    border-bottom: 2px solid #f1f5f9;
}

.pane-title {
    font-size: 1.05rem;
    font-weight: 800;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 8px;
}

.pane-hint {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
}

                        
.passage-body {
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    padding: 24px;
    font-size: 0.96rem;
    line-height: 1.75;
    color: #1e293b;
    max-height: 75vh;
    overflow-y: auto;
}

.passage-body p {
    margin-bottom: 16px;
}

.passage-body p:last-child {
    margin-bottom: 0;
}

.passage-body h3 {
    margin: 18px 0 8px 0;
    font-size: 1.05rem;
    color: var(--primary);
}

                            
.passage-loading-state,
.passage-empty-state {
    padding: 60px 20px;
    text-align: center;
    color: var(--text-muted);
}

.passage-loading-state i {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 12px;
}

.passage-empty-state .empty-icon-wrap {
    font-size: 2.5rem;
    color: #94a3b8;
    margin-bottom: 12px;
}

.empty-title {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 6px;
}

.empty-desc {
    font-size: 0.88rem;
    color: var(--text-muted);
    margin-bottom: 16px;
}

                                                            
                               
                                                               
.questions-list-wrapper {
    display: flex;
    flex-direction: column;
    gap: 18px;
    max-height: 75vh;
    overflow-y: auto;
    padding-right: 4px;
}

.question-card {
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    padding: 16px 18px;
    transition: border-color 0.15s, box-shadow 0.15s;
}

.question-card:hover {
    border-color: #cbd5e1;
}

.question-card.answered {
    border-color: #93c5fd;
    background-color: #f8fafc;
}

.question-card.correct {
    border-color: var(--success) !important;
    background-color: var(--success-light) !important;
}

.question-card.wrong {
    border-color: var(--danger) !important;
    background-color: var(--danger-light) !important;
}

.q-header {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    margin-bottom: 14px;
}

.q-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 32px;
    height: 28px;
    padding: 0 6px;
    background-color: #0f172a;
    color: #ffffff;
    font-size: 0.82rem;
    font-weight: 800;
    border-radius: var(--radius-sharp);
    flex-shrink: 0;
}

.q-type-label {
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--text-muted);
    padding: 2px 6px;
    background: #f1f5f9;
    border-radius: var(--radius-sharp);
    margin-left: auto;
    letter-spacing: 0.3px;
}

.q-text {
    font-size: 0.94rem;
    font-weight: 600;
    color: var(--text-main);
    line-height: 1.5;
    flex: 1;
}

                                                   
.tfng-options-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
}

.tfng-pill-label {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 9px 8px;
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    cursor: pointer;
    font-size: 0.86rem;
    font-weight: 600;
    color: var(--text-sub);
    transition: all 0.15s ease;
    user-select: none;
}

.tfng-pill-label input[type="radio"] {
    display: none;
}

.tfng-pill-label:hover {
    border-color: var(--primary);
    background-color: var(--primary-light);
    color: var(--primary);
}

.tfng-pill-label.selected {
    background-color: var(--primary);
    border-color: var(--primary);
    color: #ffffff;
    font-weight: 700;
}

.tfng-pill-label.disabled {
    cursor: default;
    pointer-events: none;
}

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

.mcq-option-label {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 10px 12px;
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    cursor: pointer;
    font-size: 0.88rem;
    color: var(--text-main);
    transition: all 0.15s ease;
    user-select: none;
}

.mcq-option-label input[type="radio"] {
    display: none;
}

.opt-letter {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    background-color: #f1f5f9;
    border: 1px solid #cbd5e1;
    border-radius: var(--radius-sharp);
    font-size: 0.8rem;
    font-weight: 800;
    color: var(--text-sub);
    flex-shrink: 0;
    transition: all 0.15s;
}

.opt-text {
    flex: 1;
    line-height: 1.45;
}

.mcq-option-label:hover {
    border-color: var(--primary);
    background-color: var(--primary-light);
}

.mcq-option-label:hover .opt-letter {
    background-color: var(--primary);
    border-color: var(--primary);
    color: #ffffff;
}

.mcq-option-label.selected {
    border-color: var(--primary);
    background-color: var(--primary-light);
    font-weight: 600;
}

.mcq-option-label.selected .opt-letter {
    background-color: var(--primary);
    border-color: var(--primary);
    color: #ffffff;
}

.mcq-option-label.disabled {
    cursor: default;
    pointer-events: none;
}

                                 
.q-eval-box {
    margin-top: 12px;
    padding: 10px 12px;
    border-radius: var(--radius-sharp);
    font-size: 0.84rem;
    line-height: 1.5;
}

.q-eval-box.correct {
    background-color: #dcfce7;
    border: 1px solid #86efac;
    color: #14532d;
}

.q-eval-box.wrong {
    background-color: #fee2e2;
    border: 1px solid #fca5a5;
    color: #7f1d1d;
}

.q-eval-box .explanation-text {
    margin-top: 4px;
    font-size: 0.8rem;
    color: var(--text-sub);
    font-style: italic;
}

                                                            
                        
                                                               
.reading-actions-bar {
    position: sticky;
    bottom: 0;
    margin-top: 24px;
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    padding: 12px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    box-shadow: 0 -4px 10px rgba(0, 0, 0, 0.04);
    z-index: 50;
}

.actions-status {
    font-size: 0.9rem;
    color: var(--text-sub);
}

.actions-status strong {
    color: var(--primary);
    font-weight: 800;
}

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

.btn-action {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    font-size: 0.88rem;
    font-weight: 700;
    border-radius: var(--radius-sharp);
    cursor: pointer;
    border: 1px solid transparent;
    transition: all 0.15s ease;
}

.btn-reset {
    background-color: #f1f5f9;
    color: var(--text-main);
    border-color: #cbd5e1;
}

.btn-reset:hover {
    background-color: #e2e8f0;
}

.btn-send {
    background-color: var(--primary);
    color: #ffffff;
}

.btn-send:hover {
    background-color: var(--primary-hover);
}

.btn-action:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

                                                            
                             
                                                               
.modal-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(4px);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    padding: 20px;
}

.modal-backdrop.open {
    display: flex;
}

.modal-card {
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    max-width: 680px;
    width: 100%;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-lg);
    animation: modalPop 0.2s ease-out;
}

@keyframes modalPop {
    from { opacity: 0; transform: scale(0.96); }
    to { opacity: 1; transform: scale(1); }
}

.modal-header {
    padding: 18px 24px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-badge-tag {
    font-size: 0.72rem;
    font-weight: 800;
    text-transform: uppercase;
    color: var(--primary);
    background-color: var(--primary-light);
    padding: 2px 8px;
    border-radius: var(--radius-sharp);
    display: inline-block;
    margin-bottom: 4px;
}

.modal-title {
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--text-main);
}

.modal-close-btn {
    background: transparent;
    border: none;
    font-size: 1.6rem;
    color: var(--text-muted);
    cursor: pointer;
    line-height: 1;
}

.modal-body {
    padding: 24px;
    overflow-y: auto;
    flex: 1;
}

.modal-hud-card {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    margin-bottom: 20px;
}

.hud-stat-box {
    background-color: #f8fafc;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sharp);
    padding: 14px 10px;
    text-align: center;
}

.hud-stat-box .stat-label {
    font-size: 0.76rem;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.stat-value {
    font-size: 1.45rem;
    font-weight: 800;
    color: var(--text-main);
}

.num-percent {
    color: var(--primary);
}

.cefr-badge-pill {
    display: inline-block;
    padding: 2px 10px;
    background-color: var(--primary);
    color: #ffffff;
    border-radius: var(--radius-sharp);
    font-size: 1.15rem;
}

.cefr-subname {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 2px;
}

.feedback-quote-box {
    background-color: #f8fafc;
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--primary);
    border-radius: var(--radius-sharp);
    padding: 14px 18px;
    margin-bottom: 24px;
    font-size: 0.92rem;
    color: var(--text-sub);
    position: relative;
}

.quote-icon {
    color: #94a3b8;
    margin-bottom: 6px;
    display: block;
}

.breakdown-title {
    font-size: 0.96rem;
    font-weight: 800;
    color: var(--text-main);
    margin-bottom: 12px;
}

.breakdown-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.breakdown-item {
    padding: 12px 14px;
    border-radius: var(--radius-sharp);
    border: 1px solid var(--border-color);
    background-color: #ffffff;
    font-size: 0.86rem;
}

.breakdown-item.correct {
    border-color: #86efac;
    background-color: #f0fdf4;
}

.breakdown-item.wrong {
    border-color: #fca5a5;
    background-color: #fef2f2;
}

.b-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-weight: 700;
    margin-bottom: 6px;
}

.b-answers {
    display: flex;
    gap: 16px;
    font-size: 0.82rem;
    color: var(--text-sub);
    margin-bottom: 4px;
}

.b-explanation {
    font-size: 0.8rem;
    color: var(--text-muted);
    font-style: italic;
    border-top: 1px dashed rgba(0, 0, 0, 0.1);
    padding-top: 4px;
    margin-top: 4px;
}

.modal-footer {
    padding: 16px 24px;
    border-top: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 10px;
    background-color: #f8fafc;
}

.btn-modal {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 9px 18px;
    font-size: 0.86rem;
    font-weight: 700;
    border-radius: var(--radius-sharp);
    text-decoration: none;
    cursor: pointer;
}

.btn-modal-retry {
    background-color: #ffffff;
    color: var(--text-main);
    border: 1px solid #cbd5e1;
}

.btn-modal-exit {
    background-color: var(--primary);
    color: #ffffff;
    border: 1px solid var(--primary);
}

                                                            
                         
                                                               
.toast-container {
    position: fixed;
    bottom: 24px;
    right: 24px;
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: 8px;
    pointer-events: none;
}

.toast {
    padding: 12px 18px;
    background-color: #0f172a;
    color: #ffffff;
    border-radius: var(--radius-sharp);
    font-size: 0.86rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 8px;
    box-shadow: var(--shadow-lg);
    animation: toastSlide 0.25s ease-out forwards;
    pointer-events: auto;
}

@keyframes toastSlide {
    from { transform: translateY(20px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

                                                            
                                                  
                                                               
@media (max-width: 960px) {
    .reading-top-bar {
        padding: 0 12px;
    }

    .bar-center {
        max-width: 200px;
    }

    .reading-container {
        padding: 12px 10px 80px 10px;
    }

    .reading-card {
        padding: 16px 14px;
    }

    .mobile-segmented-bar {
        display: flex;
    }

    .part4-workspace {
        grid-template-columns: 1fr;
        gap: 16px;
    }

                                                                    
    .part4-workspace.view-passage .pane-questions {
        display: none;
    }

    .part4-workspace.view-passage .pane-passage {
        display: block;
    }

    .part4-workspace.view-questions .pane-passage {
        display: none;
    }

    .part4-workspace.view-questions .pane-questions {
        display: block;
    }

    .passage-body {
        max-height: none;
        padding: 16px;
    }

    .questions-list-wrapper {
        max-height: none;
        padding-right: 0;
    }

    .reading-actions-bar {
        padding: 10px 14px;
    }

    .btn-action span {
        font-size: 0.82rem;
    }

    .modal-card {
        max-height: 95vh;
    }

    .modal-hud-card {
        grid-template-columns: 1fr;
        gap: 8px;
    }
}