:root {
    /* Thème Clair par défaut */
    --bg-color: #f8fafc;
    --surface-color: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --success-color: #10b981;
    --error-color: #ef4444;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --font-sans: 'Inter', system-ui, sans-serif;
    --font-heading: 'Outfit', sans-serif;
}

[data-theme="dark"] {
    --bg-color: #0f172a;
    --surface-color: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --primary-color: #60a5fa;
    --primary-hover: #3b82f6;
    --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.5;
    transition: background-color 0.3s ease, color 0.3s ease;
    min-height: 100vh; /* fallback */
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
}

/* Header */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    background-color: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
}

.logo {
    cursor: pointer;
}

.logo-text {
    font-family: var(--font-heading);
    font-weight: 800;
    font-size: 1.5rem;
    color: var(--primary-color);
}

.nav-menu {
    display: flex;
    gap: 1rem;
}

.nav-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-family: var(--font-sans);
    font-weight: 500;
    font-size: 1rem;
    cursor: pointer;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    transition: all 0.2s;
}

.nav-btn:hover {
    color: var(--text-primary);
    background-color: rgba(100, 116, 139, 0.1);
}

.nav-btn.active {
    color: var(--primary-color);
    background-color: rgba(59, 130, 246, 0.1);
}

.icon-btn {
    background: none;
    border: none;
    font-size: 1.25rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    color: var(--text-primary);
    transition: background-color 0.2s;
}

.icon-btn:hover {
    background-color: rgba(100, 116, 139, 0.1);
}

/* Main Container */
#app-container {
    flex: 1;
    display: flex;
    justify-content: center;
    padding: 2rem;
}

.view-content {
    width: 100%;
    max-width: 600px;
}

.view-wide {
    max-width: 1000px; /* Plus d'espace pour les tableaux */
}

/* Typography */
.page-title {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 2rem;
    margin-bottom: 0.5rem;
    text-align: center;
}

.page-subtitle {
    color: var(--text-secondary);
    text-align: center;
    margin-bottom: 2rem;
}

/* Cards & Forms */
.card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-secondary);
}

select, input[type="text"] {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

select {
    appearance: none;
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%2364748b' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    background-size: 1.2em;
    padding-right: 3rem;
}

select:focus, input[type="text"]:focus {
    border-color: var(--primary-color);
}

.btn-primary {
    width: 100%;
    padding: 1rem;
    background-color: var(--primary-color);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-family: var(--font-sans);
    font-weight: 600;
    font-size: 1.1rem;
    cursor: pointer;
    transition: background-color 0.2s;
}

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

/* Animations */
.animate-fade-in {
    animation: fadeIn 0.4s ease forwards;
}

.animate-slide-up {
    animation: slideUp 0.4s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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

/* Drill Section */
.drill-container { margin: 0 auto; display: flex; flex-direction: column; height: 100%; }
.drill-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 2rem; }
.lang-pair { display: flex; align-items: center; gap: 0.5rem; font-weight: 600; }
.lang-badge { background: var(--primary-color); color: white; padding: 0.25rem 0.75rem; border-radius: 4px; font-size: 0.9rem; }
.drill-progress { font-weight: bold; color: var(--text-secondary); }

.flashcard {
    text-align: center;
    padding: 2rem 1rem;
    margin-bottom: 2rem;
    border: none;
    border-radius: 12px;
    flex: 1;
    display: flex;
    flex-direction: column;
}
.word-source { font-size: 2.5rem; font-family: var(--font-heading); font-weight: 700; margin-bottom: 1.5rem; }
.input-section { margin-bottom: 1rem; }
.input-section input { font-size: 1.5rem; text-align: center; border-width: 0 0 2px 0; border-radius: 0; padding: 0.5rem; background: transparent; }
.input-section input:focus { border-color: var(--primary-color); }
.hidden { display: none !important; }

.result-section { margin-top: 2rem; animation: slideUp 0.3s ease; }
.result-comparison { display: flex; flex-direction: column; gap: 0.5rem; margin-bottom: 1.5rem; padding: 1.5rem; background: rgba(0,0,0,0.03); border-radius: 8px; }
.comparison-line { display: flex; align-items: center; font-size: 1.5rem; }
.comparison-label { min-width: 140px; text-align: right; margin-right: 1.5rem; font-size: 1rem; color: var(--text-secondary); white-space: nowrap; }
.comparison-text { font-family: monospace; font-size: 1.75rem; font-weight: 600; text-align: left; }
.user-saisie { color: var(--error-color); }
.expected-saisie { color: var(--success-color); }

.speak-btn {
    color: #ffffff;
    transition: transform 0.2s, background-color 0.2s, color 0.2s;
    border-radius: 50%;
}
[data-theme="light"] .speak-btn {
    color: var(--text-secondary);
}
.speak-btn:hover {
    transform: scale(1.1);
    background-color: rgba(59, 130, 246, 0.1) !important;
}
.speak-btn:active {
    transform: scale(0.95);
}

input[type="text"].rewrite-field {
    border: none;
    background: transparent;
    padding: 0;
    margin: 0;
    width: 100%;
    max-width: 300px;
    outline: none;
    box-shadow: none;
    font-family: monospace;
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary);
}

[data-theme="light"] input[type="text"].rewrite-field {
    color: #000000;
}

input[type="text"].rewrite-field::placeholder {
    color: var(--text-secondary);
    opacity: 0.4;
}

input[type="text"].rewrite-field:focus {
    border: none;
    outline: none;
    box-shadow: none;
}

input[type="text"].rewrite-field.correct {
    color: var(--success-color) !important;
}

.status-banner { padding: 1rem; border-radius: 8px; font-weight: bold; font-size: 1.25rem; margin-bottom: 1.5rem; text-align: center; }
.keyboard-hints { display: flex; justify-content: center; gap: 1.5rem; color: var(--text-secondary); font-size: 0.9rem; }
.hint { display: flex; align-items: center; gap: 0.5rem; }
kbd { background: var(--surface-color); border: 1px solid var(--border-color); padding: 0.2rem 0.5rem; border-radius: 4px; font-family: monospace; font-size: 0.85rem; color: var(--text-primary); }

.session-actions { text-align: center; }
.data-table { width: 100%; border-collapse: collapse; margin-top: 1rem; table-layout: fixed; }
.data-table th, .data-table td { padding: 0.75rem; text-align: left; border-bottom: 1px solid var(--border-color); overflow: hidden; text-overflow: ellipsis; }
.data-table th { color: var(--text-secondary); font-weight: 500; }
.btn-ghost { background: none; border: none; color: var(--text-secondary); cursor: pointer; text-decoration: underline; }
.btn-ghost:hover { color: var(--error-color); }

/* Prevent table overflow on desktop */
.table-container {
    width: 100%;
    overflow-x: auto;
}

/* Bulk actions bar in Progression view */
.bulk-actions-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: rgba(59, 130, 246, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 0.75rem 1rem;
    margin: 1rem 0;
    animation: fadeIn 0.2s ease;
}
.bulk-actions-bar.hidden {
    display: none !important;
}
#bulk-select-count {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--primary-color);
}
.bulk-buttons {
    display: flex;
    gap: 0.5rem;
}
.btn-small {
    padding: 0.4rem 0.8rem;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 6px;
    cursor: pointer;
    border: none;
    font-family: var(--font-sans);
    transition: all 0.2s;
}
.btn-primary-action {
    background-color: var(--primary-color);
    color: white;
}
.btn-primary-action:hover:not(:disabled) {
    background-color: var(--primary-hover);
}
.btn-secondary-action {
    background-color: var(--text-secondary);
    color: white;
}
.btn-secondary-action:hover:not(:disabled) {
    background-color: var(--text-primary);
    color: var(--bg-color);
}
.btn-small:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

/* Clickable Status Cells */
.status-cell {
    cursor: pointer;
    user-select: none;
    text-align: center !important;
    font-size: 1rem;
    line-height: 1;
    font-weight: bold;
    white-space: nowrap;
    min-width: 80px;
    transition: background-color 0.2s;
    height: 48px; /* ensures a good click target */
}
.status-cell:hover {
    background-color: rgba(59, 130, 246, 0.05);
}
.status-cell.actif:hover::after {
    content: '✓';
    opacity: 0.3;
    color: var(--text-secondary);
}
.status-cell.valide {
    color: var(--success-color);
}

/* Stats Layout */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 350px));
    justify-content: center;
    gap: 1.5rem;
    margin-top: 1rem;
}
.stat-card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    gap: 1rem;
}
.stat-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.75rem;
    min-height: 72px;
}
.stat-pair-name {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--primary-color);
}
.stat-percentage-badge {
    font-size: 1.1rem;
    font-weight: 800;
    color: var(--success-color);
    background-color: rgba(16, 185, 129, 0.1);
    padding: 0.25rem 0.5rem;
    border-radius: 6px;
    white-space: nowrap;
}
.stat-body {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}
.stat-row {
    display: flex;
    justify-content: space-between;
    font-size: 0.95rem;
}
.stat-label {
    color: var(--text-secondary);
    white-space: nowrap;
}
.stat-value {
    font-weight: 600;
}

/* Progress bar */
.stat-progress-container {
    background-color: var(--border-color);
    height: 8px;
    border-radius: 4px;
    overflow: hidden;
    margin-top: 0.5rem;
}
.stat-progress-bar {
    background-color: var(--success-color);
    height: 100%;
    width: 0%;
    transition: width 0.6s cubic-bezier(0.1, 1, 0.1, 1);
}

/* Checkbox alignment */
.data-table th input[type="checkbox"],
.data-table td input[type="checkbox"] {
    cursor: pointer;
    width: 16px;
    height: 16px;
    accent-color: var(--primary-color);
}
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.mobile-menu-btn {
    display: none !important;
}

.btn-drill-action {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: 6px;
    cursor: pointer;
    border: none;
    font-family: var(--font-sans);
    transition: all 0.2s;
}

.btn-drill-action.btn-secondary-action {
    background-color: var(--surface-color);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}
.btn-drill-action.btn-secondary-action:hover {
    background-color: rgba(239, 68, 68, 0.1);
    color: #ef4444;
    border-color: rgba(239, 68, 68, 0.3);
}

[data-theme="dark"] .btn-drill-action.btn-secondary-action {
    background-color: #1e293b;
    color: #f8fafc;
    border: 1px solid #475569;
}

[data-theme="dark"] .btn-drill-action.btn-secondary-action:hover {
    background-color: rgba(248, 113, 113, 0.15);
    color: #fca5a5;
    border-color: rgba(248, 113, 113, 0.4);
}

[data-theme="dark"] .btn-drill-action.btn-secondary-action kbd {
    background-color: #334155;
    color: #f8fafc;
    border-color: #64748b;
}

#btn-mobile-secondary {
    background-color: var(--surface-color);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}
[data-theme="dark"] #btn-mobile-secondary {
    background-color: #1e293b;
    color: #f8fafc;
    border: 1px solid #475569;
}

.mobile-only-btn {
    display: none !important;
    margin-top: auto !important;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Responsive / Mobile optimizations */
@media (max-width: 640px) {
    .mobile-menu-btn {
        display: inline-flex !important;
        align-items: center;
        justify-content: center;
        color: var(--text-primary);
    }
    
    .mobile-only-btn {
        display: block !important;
    }
    
    #mobile-action-container {
        display: flex !important;
    }

    .app-header {
        position: relative;
        padding: 0.75rem 1rem;
    }

    .nav-menu {
        display: none !important;
        position: absolute;
        top: 100%;
        right: 1rem;
        background-color: var(--surface-color);
        border: 1px solid var(--border-color);
        border-radius: 12px;
        box-shadow: var(--shadow);
        flex-direction: column;
        gap: 0.25rem;
        padding: 0.5rem;
        z-index: 1000;
        min-width: 180px;
        animation: slideUp 0.2s cubic-bezier(0.16, 1, 0.3, 1) forwards;
    }

    .nav-menu.open {
        display: flex !important;
    }

    .nav-btn {
        width: 100%;
        text-align: left;
        padding: 0.6rem 1rem;
        font-size: 0.95rem;
    }

    /* Main Container & Cards padding reduction */
    #app-container {
        padding: 1rem 0.5rem;
    }
    .view-content {
        max-width: 100%;
    }
    .card {
        padding: 1.25rem 1rem;
    }
    .form-group {
        margin-bottom: 1rem;
    }
    
    /* Drill / Exercise */
    .drill-header {
        margin-bottom: 1rem;
    }
    .word-source {
        font-size: 2rem;
        margin-bottom: 1rem;
    }
    .input-section input {
        font-size: 1.25rem;
    }
    .flashcard {
        padding: 1rem 0.5rem;
        margin-bottom: 0;
        cursor: pointer;
        transition: background-color 0.2s ease, transform 0.1s ease;
    }
    .flashcard:hover {
        background-color: rgba(100, 116, 139, 0.03);
    }
    .flashcard:active {
        transform: scale(0.99);
    }
    .status-banner {
        padding: 0.75rem;
        margin-bottom: 1rem;
        font-size: 1.1rem;
    }
    .result-comparison {
        padding: 1rem;
        margin-bottom: 1rem;
    }

    /* Progression page filters stacking */
    .progress-filters {
        flex-direction: column;
        gap: 0.75rem;
    }
    .table-container {
        width: 100%;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }
    .data-table th, .data-table td {
        padding: 0.5rem 0.4rem;
        font-size: 0.85rem;
    }
    .status-cell {
        font-size: 1rem;
        width: 60px;
        height: 36px;
    }
}

/* Stacking comparison lines on extra small screens */
@media (max-width: 480px) {
    .comparison-line {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.15rem;
        margin-bottom: 0.5rem;
    }
    .comparison-label {
        min-width: 0;
        text-align: left;
        margin-right: 0;
        font-size: 0.8rem;
    }
    .comparison-text {
        font-size: 1.25rem;
    }
    input[type="text"].rewrite-field {
        font-size: 1.25rem !important;
        max-width: 100%;
    }
    .bulk-actions-bar {
        flex-direction: column;
        gap: 0.75rem;
        align-items: flex-start;
    }
    .bulk-buttons {
        width: 100%;
        justify-content: flex-end;
    }
    .keyboard-hints {
        flex-direction: column;
        align-items: center;
        gap: 0.5rem;
    }
}

/* --- Styles de la page Démarche Projet --- */
.about-grid {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    margin-top: 1.5rem;
}
.about-card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--shadow);
    transition: transform 0.2s, border-color 0.2s;
}
.about-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
}
.about-card h2 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.75rem;
    margin-top: 0;
}
.about-card p, .about-card li {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--text-secondary);
}
.pillar-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(110px, 1fr));
    gap: 0.75rem;
    margin-top: 1.5rem;
}
.pillar-box {
    background: rgba(100, 116, 139, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 0.75rem;
    text-align: center;
    transition: background 0.2s;
}
.pillar-box:hover {
    background: rgba(100, 116, 139, 0.1);
}
.pillar-icon {
    font-size: 1.5rem;
    margin-bottom: 0.25rem;
    display: block;
}
.pillar-title {
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--text-primary);
    display: block;
    margin-bottom: 0.15rem;
}
.pillar-desc {
    font-size: 0.75rem !important;
    color: var(--text-secondary);
    line-height: 1.3;
    display: block;
}
.credits-banner {
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.03) 0%, rgba(16, 185, 129, 0.03) 100%);
    border: 1px dashed var(--border-color);
    border-radius: 16px;
    padding: 2.5rem 2rem;
    text-align: center;
    margin-top: 2.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.25rem;
}
.avatar-badge {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--success-color) 100%);
    color: white;
    font-weight: 800;
    font-size: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 15px rgba(37, 99, 235, 0.2);
}
.linkedin-badge-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
    background-color: #0077b5;
    color: white !important;
    padding: 0.65rem 1.5rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.9rem;
    text-decoration: none;
    transition: transform 0.2s, box-shadow 0.2s;
    margin-top: 0.5rem;
    border: none;
    cursor: pointer;
}
.linkedin-badge-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 119, 181, 0.35);
}
.tags-container {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.6rem;
    margin-top: 0.5rem;
}
.tag-badge {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 0.35rem 0.9rem;
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 600;
    font-family: var(--font-sans);
}

/* --- Styles des badges de type de mot (drill) --- */
.type-badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 700;
    border-radius: 20px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-family: var(--font-sans);
    transition: all 0.2s ease;
}
.type-badge.hidden {
    display: none !important;
}
.type-badge.verbe {
    background-color: rgba(244, 63, 94, 0.15);
    color: #fb7185;
    border: 1px solid rgba(244, 63, 94, 0.3);
}
.type-badge.nom {
    background-color: rgba(59, 130, 246, 0.15);
    color: #60a5fa;
    border: 1px solid rgba(59, 130, 246, 0.3);
}
.type-badge.adjectif {
    background-color: rgba(16, 185, 129, 0.15);
    color: #34d399;
    border: 1px solid rgba(16, 185, 129, 0.3);
}
.type-badge.adverbe {
    background-color: rgba(245, 158, 11, 0.15);
    color: #fbbf24;
    border: 1px solid rgba(245, 158, 11, 0.3);
}
.type-badge.conjonction {
    background-color: rgba(6, 182, 212, 0.15);
    color: #22d3ee;
    border: 1px solid rgba(6, 182, 212, 0.3);
}

.example-highlight {
    font-weight: 700;
    color: var(--primary-color);
}


/* --- Context Drill Styles --- */
.context-word-btn {
    padding: 0.5rem 1rem;
    background: var(--surface-color);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-primary);
    cursor: grab;
    transition: all 0.2s;
    user-select: none;
    box-shadow: var(--shadow-sm);
}

.context-word-btn:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.context-word-btn:active, .context-word-btn.dragging {
    cursor: grabbing;
    opacity: 0.8;
    transform: scale(0.95);
}

.context-word-btn.selected {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.context-word-btn.success-match {
    background: var(--success-color);
    color: white;
    border-color: var(--success-color);
    transform: scale(1.1);
    opacity: 0;
    transition: all 0.5s ease-out;
}

.context-sentence-card {
    background: var(--surface-color);
    border-radius: 12px;
    padding: 1.25rem;
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
    transition: all 0.3s;
}

.context-sentence-card.matched {
    background: rgba(16, 185, 129, 0.1);
    border-color: var(--success-color);
    opacity: 0;
    transform: translateX(20px);
    pointer-events: none;
}

.context-sentence-text {
    font-size: 1.1rem;
    color: var(--text-primary);
    line-height: 1.6;
    flex: 1;
}

.context-dropzone {
    display: inline-block;
    min-width: 100px;
    height: 34px;
    border: 2px dashed var(--border-color);
    border-radius: 6px;
    vertical-align: middle;
    margin: 0 0.4rem;
    background: rgba(0,0,0,0.02);
    transition: all 0.2s;
    cursor: pointer;
}

.context-dropzone.drag-over {
    border-color: var(--primary-color);
    background: rgba(59, 130, 246, 0.1);
    transform: scale(1.05);
}

.context-dropzone.selectable {
    border-color: var(--primary-color);
    border-style: solid;
    background: rgba(59, 130, 246, 0.05);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.context-dropzone.success {
    border-color: var(--success-color);
    border-style: solid;
    background: var(--success-color);
    color: white;
    font-weight: 600;
    text-align: center;
    line-height: 30px;
    font-size: 1.05rem;
}


/* Segmented Control for Drill Mode */
.segmented-control .segment-btn {
    color: var(--text-secondary);
}
.segmented-control input[type="radio"]:checked + .segment-btn {
    background-color: var(--primary-color);
    color: white;
}

/* Highlight bold text in About page */
.about-content strong {
    font-weight: 700;
    color: var(--primary-color);
}