/* exercise engine styles (drag-to-order, fill-in-blank, matching)
   extracted from styles.css -- do not duplicate in the source file */

/* ===== exercises ===== */
.exercise-container {
    max-width: 700px;
    margin: 0 auto;
}

.exercise-header {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
}

.exercise-title {
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--color-text);
}

.exercise-progress {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    min-width: 120px;
}

.exercise-progress-bar {
    flex: 1;
    height: 6px;
    background: var(--color-border);
    border-radius: 3px;
    overflow: hidden;
}

.exercise-progress-fill {
    height: 100%;
    background: var(--color-primary);
    border-radius: 3px;
    transition: width 0.3s ease;
}

.exercise-progress-text {
    font-size: 0.8rem;
    color: var(--color-text-muted);
    white-space: nowrap;
}

.exercise-type-badge {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    background: var(--color-primary);
    color: #fff;
}

.exercise-question {
    font-size: 1.05rem;
    font-weight: 500;
    color: var(--color-text);
    margin-bottom: 1.25rem;
    line-height: 1.6;
}

.fill-blank-inline {
    display: inline-block;
    min-width: 80px;
    border-bottom: 2px dashed var(--color-primary);
    color: var(--color-primary);
    font-weight: 600;
    text-align: center;
    padding: 0 0.25rem;
}

.exercise-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.5rem;
    margin-top: 1.25rem;
}

/* drag-to-order */
.drag-order-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.drag-order-item {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    padding: 0.65rem 0.85rem;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    cursor: grab;
    user-select: none;
    transition: transform 0.15s, box-shadow 0.15s, border-color 0.2s;
}

.drag-order-item:hover {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

.drag-order-item:active {
    cursor: grabbing;
}

.drag-order-dragging {
    opacity: 0.5;
    transform: scale(0.98);
}

.drag-handle {
    color: var(--color-text-muted);
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.drag-order-num {
    width: 22px;
    height: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--color-primary);
    color: #fff;
    font-size: 0.7rem;
    font-weight: 600;
    flex-shrink: 0;
}

.drag-order-text {
    flex: 1;
    font-size: 0.9rem;
    color: var(--color-text);
}

.drag-order-arrows {
    display: flex;
    flex-direction: column;
    gap: 2px;
    flex-shrink: 0;
}

.drag-arrow {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 22px;
    height: 22px;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    background: transparent;
    color: var(--color-text-muted);
    cursor: pointer;
    padding: 0;
    transition: background-color 0.15s, color 0.15s;
}

.drag-arrow:hover:not(:disabled) {
    background: var(--color-primary);
    color: #fff;
    border-color: var(--color-primary);
}

.drag-arrow:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.exercise-item-correct {
    border-color: var(--color-success) !important;
    background: rgba(16, 185, 129, 0.08) !important;
}

.exercise-item-incorrect {
    border-color: var(--color-danger) !important;
    background: rgba(239, 68, 68, 0.08) !important;
}

/* fill-in-the-blank */
.fill-blank-area {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.fill-blank-slots {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.fill-blank-slot {
    flex: 1;
    min-width: 140px;
}

.fill-blank-label {
    display: block;
    font-size: 0.75rem;
    color: var(--color-text-muted);
    margin-bottom: 0.35rem;
    font-weight: 500;
}

.fill-blank-dropzone {
    min-height: 44px;
    border: 2px dashed var(--color-border);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem;
    transition: border-color 0.2s, background-color 0.2s;
    cursor: pointer;
}

.fill-blank-dropzone:hover {
    border-color: var(--color-primary);
}

.fill-blank-dropzone-hover {
    border-color: var(--color-primary);
    background: rgba(99, 102, 241, 0.05);
}

.fill-blank-placed {
    font-weight: 500;
    color: var(--color-primary);
    font-size: 0.9rem;
}

.exercise-slot-correct {
    border-color: var(--color-success) !important;
    background: rgba(16, 185, 129, 0.08) !important;
}

.exercise-slot-correct .fill-blank-placed {
    color: var(--color-success);
}

.exercise-slot-incorrect {
    border-color: var(--color-danger) !important;
    background: rgba(239, 68, 68, 0.08) !important;
}

.exercise-slot-incorrect .fill-blank-placed {
    color: var(--color-danger);
    text-decoration: line-through;
}

.fill-blank-correct-answer {
    display: block;
    font-size: 0.75rem;
    color: var(--color-success);
    margin-top: 0.2rem;
    font-weight: 600;
}

.fill-blank-bank {
    padding: 0.75rem;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
}

.fill-blank-bank-label {
    display: block;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.04em;
    margin-bottom: 0.5rem;
}

.fill-blank-words {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
}

.fill-blank-word {
    padding: 0.35rem 0.65rem;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    background: transparent;
    color: var(--color-text);
    font-size: 0.85rem;
    cursor: pointer;
    transition: border-color 0.15s, background-color 0.15s;
}

.fill-blank-word:hover {
    border-color: var(--color-primary);
    background: rgba(99, 102, 241, 0.05);
}

.fill-blank-word-selected {
    border-color: var(--color-primary);
    background: rgba(99, 102, 241, 0.12);
    color: var(--color-primary);
    font-weight: 500;
}

/* matching */
.matching-area {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.matching-columns {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 0.5rem;
    align-items: start;
}

.matching-column {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.matching-lines {
    width: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.matching-item {
    padding: 0.55rem 0.75rem;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-surface);
    color: var(--color-text);
    font-size: 0.85rem;
    cursor: pointer;
    text-align: left;
    transition: border-color 0.15s, background-color 0.15s;
    line-height: 1.4;
}

.matching-item:hover {
    border-color: var(--color-primary);
}

.matching-item-active {
    border-color: var(--color-primary);
    background: rgba(99, 102, 241, 0.1);
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

.matching-item-matched {
    border-color: var(--color-primary);
    background: rgba(99, 102, 241, 0.06);
    opacity: 0.8;
}

.matching-pairs-display {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    min-height: 32px;
}

.matching-hint {
    font-size: 0.8rem;
    color: var(--color-text-muted);
    font-style: italic;
}

.matching-pair-chip {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    padding: 0.25rem 0.55rem;
    border-radius: 6px;
    background: rgba(99, 102, 241, 0.08);
    border: 1px solid rgba(99, 102, 241, 0.2);
    font-size: 0.75rem;
    color: var(--color-primary);
}

.matching-pair-chip svg {
    flex-shrink: 0;
    opacity: 0.6;
}

/* exercise feedback */
.exercise-feedback {
    margin-top: 1rem;
}

.exercise-feedback-inner {
    padding: 0.85rem 1rem;
    border-radius: var(--radius);
    border-left: 3px solid;
}

.exercise-feedback-correct {
    background: rgba(16, 185, 129, 0.08);
    border-color: var(--color-success);
}

.exercise-feedback-incorrect {
    background: rgba(239, 68, 68, 0.08);
    border-color: var(--color-danger);
}

.exercise-feedback-icon {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    margin-bottom: 0.35rem;
}

.exercise-feedback-correct .exercise-feedback-icon {
    color: var(--color-success);
}

.exercise-feedback-incorrect .exercise-feedback-icon {
    color: var(--color-danger);
}

.exercise-feedback-text {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    line-height: 1.5;
}

/* exercise results */
.exercise-results {
    text-align: center;
    padding: 2rem;
}

.exercise-results-icon {
    margin-bottom: 1rem;
}

.exercise-results-pass { color: var(--color-success); }
.exercise-results-fail { color: var(--color-warning); }

.exercise-results-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 1rem;
}

.exercise-score-display {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 0.3rem;
    margin-bottom: 0.5rem;
}

.exercise-score-number {
    font-size: 2rem;
    font-weight: 800;
    color: var(--color-primary);
}

.exercise-score-divider {
    font-size: 1.5rem;
    color: var(--color-text-muted);
}

.exercise-score-total {
    font-size: 1.5rem;
    color: var(--color-text-muted);
}

.exercise-score-percent {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    margin-bottom: 1.5rem;
}

.exercise-results-actions {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
}

/* responsive */
@media (max-width: 480px) {
    .exercise-header {
        gap: 0.5rem;
    }

    .matching-columns {
        grid-template-columns: 1fr;
        gap: 0.75rem;
    }

    .matching-lines {
        display: none;
    }

    .matching-column {
        border: 1px solid var(--color-border);
        border-radius: var(--radius);
        padding: 0.5rem;
    }

    .drag-order-item {
        padding: 0.5rem 0.65rem;
    }

    .fill-blank-slots {
        flex-direction: column;
    }
}

@media (prefers-reduced-motion: reduce) {
    .drag-order-item,
    .fill-blank-word,
    .matching-item {
        transition: none;
    }
}