/**
 * === CARDS.CSS ===
 * /assets/css/cards.css
 * НАЗНАЧЕНИЕ: Стили для карточек интервального повторения
 * СВЯЗИ: style.css, components.css
 * РАЗМЕР: ~300 строк
 */

/* ============================================
   CARDS TYPE FILTER
   ============================================ */

.cards-type-filter {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xl);
    padding: var(--spacing-sm);
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    overflow-x: auto;
}

.filter-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    background: transparent;
    border: none;
    border-radius: var(--radius-md);
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.filter-btn:hover {
    color: var(--text-primary);
    background: var(--bg-card);
}

.filter-btn.active {
    color: var(--color-blue);
    background: var(--bg-card);
    box-shadow: var(--shadow-sm);
}

.filter-btn .icon {
    width: 18px;
    height: 18px;
}

.filter-btn[data-type="quiz"].active {
    color: var(--color-blue);
}

.filter-btn[data-type="matching"].active {
    color: var(--color-purple);
}

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

.filter-btn.disabled:hover {
    background: transparent;
    color: var(--text-muted);
}

/* ============================================
   CARDS SESSION
   ============================================ */

.cards-session {
    max-width: 700px;
    margin: 0 auto;
    padding: var(--spacing-lg) 0;
}

.session-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.session-progress {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-muted);
    white-space: nowrap;
}

.session-header .progress-bar {
    flex: 1;
}

/* ============================================
   FLASHCARD
   ============================================ */

.flashcard {
    perspective: 1000px;
    min-height: 400px;
    cursor: pointer;
}

.flashcard__inner {
    position: relative;
    width: 100%;
    height: 100%;
    min-height: 400px;
    text-align: center;
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

.flashcard.flipped .flashcard__inner {
    transform: rotateY(180deg);
}

.flashcard__front,
.flashcard__back {
    position: absolute;
    width: 100%;
    min-height: 400px;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.flashcard__front {
    background: var(--bg-card);
    border: 2px solid var(--color-gold-dark);
    box-shadow: var(--shadow-gold);
}

.flashcard__back {
    background: linear-gradient(135deg, var(--bg-card) 0%, rgba(74, 144, 217, 0.1) 100%);
    border: 2px solid var(--color-blue);
    transform: rotateY(180deg);
}

.flashcard__section {
    display: inline-block;
    padding: 4px 12px;
    background: var(--color-gold-light);
    color: var(--text-dark);
    border-radius: var(--radius-full);
    font-size: 0.8rem;
    font-weight: 500;
    margin-bottom: var(--spacing-md);
}

.flashcard__question {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.4;
    margin-bottom: var(--spacing-lg);
}

.flashcard__hint {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-muted);
    font-size: 0.9rem;
    font-style: italic;
    margin-bottom: var(--spacing-lg);
}

.flashcard__hint svg {
    width: 16px;
    height: 16px;
    color: var(--color-gold);
}

.flashcard__answer {
    font-family: var(--font-heading);
    font-size: 1.4rem;
    font-weight: 500;
    color: var(--text-primary);
    line-height: 1.5;
    margin-bottom: var(--spacing-md);
}

.flashcard__explanation {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
    padding: var(--spacing-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
    text-align: left;
    width: 100%;
}

/* ============================================
   QUALITY BUTTONS (SM-2)
   ============================================ */

.quality-buttons {
    width: 100%;
}

.quality-label {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-md);
}

.quality-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-sm);
}

.quality-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-card);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.quality-btn:hover {
    transform: translateY(-2px);
}

.quality-icon {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-xs);
}

.quality-text {
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-muted);
}

/* Цвета для разных оценок */
.quality-btn.quality-0:hover,
.quality-btn.quality-1:hover {
    border-color: var(--color-danger);
    background: rgba(239, 68, 68, 0.1);
}

.quality-btn.quality-2:hover {
    border-color: var(--color-warning);
    background: rgba(245, 158, 11, 0.1);
}

.quality-btn.quality-3:hover,
.quality-btn.quality-4:hover {
    border-color: var(--color-success);
    background: rgba(16, 185, 129, 0.1);
}

.quality-btn.quality-5:hover {
    border-color: var(--color-gold);
    background: var(--color-gold-light);
}

/* Free mode buttons */
.quality-buttons.free-mode {
    text-align: center;
}

.premium-hint {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    font-size: 0.85rem;
}

.premium-hint svg {
    width: 16px;
    height: 16px;
    color: var(--color-gold);
}

/* ============================================
   SESSION COMPLETE
   ============================================ */

.session-complete {
    padding: var(--spacing-xxl) 0;
}

.complete-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-lg);
}

.session-complete h2 {
    font-family: var(--font-heading);
    font-size: 2rem;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.session-stats {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
    padding: var(--spacing-lg);
    background: var(--bg-card);
    border-radius: var(--radius-lg);
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-value {
    font-family: var(--font-heading);
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-gold);
}

.stat-label {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* ============================================
   CARDS STATS (HEADER)
   ============================================ */

.cards-stats {
    display: flex;
    gap: var(--spacing-lg);
    justify-content: center;
    margin-bottom: var(--spacing-lg);
}

.cards-stats .stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-card);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.cards-stats .stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-blue);
}

.cards-stats .stat-label {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* ============================================
   KEYBOARD HINTS
   ============================================ */

.keyboard-hints {
    font-size: 0.8rem;
}

.keyboard-hints span {
    margin: 0 var(--spacing-sm);
}

/* ============================================
   EMPTY STATE
   ============================================ */

.empty-state .empty-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-md);
}

/* ============================================
   CARD TYPE BADGE
   ============================================ */

.card-type-badge {
    font-size: 0.75rem;
    padding: 4px 10px;
    border-radius: var(--radius-full);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.card-type-simple {
    background: var(--bg-secondary);
    color: var(--text-muted);
}

.card-type-quiz {
    background: rgba(59, 130, 246, 0.2);
    color: var(--color-blue);
}

.card-type-matching {
    background: rgba(139, 92, 246, 0.2);
    color: var(--color-purple);
}

/* ============================================
   QUIZ CARD (выбор из вариантов)
   ============================================ */

.quiz-card {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    text-align: center;
}

.quiz-question {
    font-family: var(--font-heading);
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.4;
    margin-bottom: var(--spacing-lg);
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
}

.quiz-option {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
    text-align: left;
}

.quiz-option:hover:not(.disabled) {
    border-color: var(--color-blue);
    background: rgba(59, 130, 246, 0.1);
}

.quiz-option.selected {
    border-color: var(--color-blue);
    background: rgba(59, 130, 246, 0.15);
}

.quiz-option.correct {
    border-color: var(--color-success);
    background: rgba(16, 185, 129, 0.2);
}

.quiz-option.incorrect {
    border-color: var(--color-danger);
    background: rgba(239, 68, 68, 0.2);
}

.quiz-option.disabled {
    cursor: not-allowed;
    opacity: 0.7;
}

.quiz-option-letter {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: var(--radius-full);
    background: var(--bg-card);
    font-weight: 600;
    color: var(--text-muted);
    flex-shrink: 0;
}

.quiz-option.selected .quiz-option-letter {
    background: var(--color-blue);
    color: white;
}

.quiz-option.correct .quiz-option-letter {
    background: var(--color-success);
    color: white;
}

.quiz-option.incorrect .quiz-option-letter {
    background: var(--color-danger);
    color: white;
}

.quiz-option-text {
    flex: 1;
    font-size: 1rem;
    color: var(--text-primary);
}

.quiz-actions {
    display: flex;
    justify-content: center;
}

/* ============================================
   MATCHING CARD (соответствия)
   ============================================ */

.matching-card {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    text-align: center;
}

.matching-question {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.4;
    margin-bottom: var(--spacing-lg);
}

.matching-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.matching-column {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.matching-left-item,
.matching-right-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.matching-left-item:hover,
.matching-right-item:hover {
    border-color: var(--color-purple);
}

.matching-left-item.selected {
    border-color: var(--color-purple);
    background: rgba(139, 92, 246, 0.15);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.2);
}

.matching-left-item.matched,
.matching-right-item.matched {
    border-color: var(--color-blue);
    background: rgba(59, 130, 246, 0.1);
}

.matching-left-item.correct {
    border-color: var(--color-success);
    background: rgba(16, 185, 129, 0.2);
}

.matching-left-item.incorrect {
    border-color: var(--color-danger);
    background: rgba(239, 68, 68, 0.2);
}

.matching-number,
.matching-letter {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: var(--radius-full);
    background: var(--bg-card);
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-muted);
    flex-shrink: 0;
}

.matching-left-item.selected .matching-number {
    background: var(--color-purple);
    color: white;
}

.matching-left-item.matched .matching-number,
.matching-right-item.matched .matching-letter {
    background: var(--color-blue);
    color: white;
}

.matching-left-item.correct .matching-number {
    background: var(--color-success);
    color: white;
}

.matching-left-item.incorrect .matching-number {
    background: var(--color-danger);
    color: white;
}

.matching-text {
    flex: 1;
    font-size: 0.95rem;
    color: var(--text-primary);
    text-align: left;
}

.matching-connector {
    width: 12px;
    height: 2px;
    background: transparent;
    margin-left: auto;
    transition: background var(--transition-normal);
}

.matching-left-item.matched .matching-connector {
    background: var(--color-blue);
}

.matching-actions {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
}

/* Прогресс matching */
.matching-progress {
    margin-bottom: var(--spacing-md);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    display: inline-block;
}

.matching-progress-text {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.matching-progress-text strong {
    color: var(--color-success);
    font-weight: 700;
}

/* Стили для правого элемента при выборе и верном ответе */
.matching-right-item.selected {
    border-color: var(--color-purple);
    background: rgba(139, 92, 246, 0.15);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.2);
}

.matching-right-item.selected .matching-letter {
    background: var(--color-purple);
    color: white;
}

.matching-right-item.correct {
    border-color: var(--color-success);
    background: rgba(16, 185, 129, 0.2);
    cursor: default;
}

.matching-right-item.correct .matching-letter {
    background: var(--color-success);
    color: white;
}

/* Анимация красной вспышки при неверном ответе */
@keyframes incorrectFlash {
    0% {
        border-color: var(--color-danger);
        background: rgba(239, 68, 68, 0.3);
        transform: scale(1);
    }
    25% {
        transform: scale(1.02);
    }
    50% {
        border-color: var(--color-danger);
        background: rgba(239, 68, 68, 0.5);
        transform: scale(1);
    }
    100% {
        border-color: var(--border-color);
        background: var(--bg-secondary);
        transform: scale(1);
    }
}

.matching-left-item.incorrect-flash,
.matching-right-item.incorrect-flash {
    animation: incorrectFlash 0.5s ease-out;
}

.matching-left-item.incorrect-flash .matching-number,
.matching-right-item.incorrect-flash .matching-letter {
    background: var(--color-danger);
    color: white;
}

/* Отключаем hover для уже угаданных */
.matching-left-item.correct:hover,
.matching-right-item.correct:hover {
    border-color: var(--color-success);
    cursor: default;
}

/* ============================================
   RESPONSIVE
   ============================================ */

@media (max-width: 768px) {
    .flashcard {
        min-height: 350px;
    }

    .flashcard__inner {
        min-height: 350px;
    }

    .flashcard__front,
    .flashcard__back {
        min-height: 350px;
        padding: var(--spacing-lg);
    }

    .flashcard__question {
        font-size: 1.2rem;
    }

    .flashcard__answer {
        font-size: 1.1rem;
    }

    .quality-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .session-stats {
        flex-direction: column;
        gap: var(--spacing-md);
    }

    .cards-stats {
        flex-wrap: wrap;
    }

    .keyboard-hints {
        display: none;
    }

    /* Quiz responsive */
    .quiz-card {
        padding: var(--spacing-lg);
    }

    .quiz-question {
        font-size: 1.2rem;
    }

    .quiz-option {
        padding: var(--spacing-sm) var(--spacing-md);
    }

    .quiz-option-letter {
        width: 28px;
        height: 28px;
        font-size: 0.9rem;
    }

    /* Matching responsive */
    .matching-card {
        padding: var(--spacing-lg);
    }

    .matching-question {
        font-size: 1.1rem;
    }

    .matching-container {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .matching-column {
        gap: var(--spacing-xs);
    }

    .matching-left {
        padding-bottom: var(--spacing-md);
        border-bottom: 1px solid var(--border-color);
    }

    .matching-left-item,
    .matching-right-item {
        padding: var(--spacing-sm) var(--spacing-md);
    }

    .matching-number,
    .matching-letter {
        width: 24px;
        height: 24px;
        font-size: 0.8rem;
    }

    .matching-text {
        font-size: 0.9rem;
    }

    .matching-actions {
        flex-direction: column;
    }

    .matching-actions .btn {
        width: 100%;
    }
}

/* ============================================
   PRONUNCIATION TERMS
   ============================================ */

.card-terms {
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.card-terms-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-sm);
}

.card-terms-label .icon {
    width: 16px;
    height: 16px;
}

.card-terms-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.btn-pronunciation {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-size: 0.9rem;
    color: var(--text-primary);
}

.btn-pronunciation:hover {
    background: var(--color-blue);
    border-color: var(--color-blue);
    color: white;
    transform: scale(1.02);
}

.btn-pronunciation .icon {
    width: 16px;
    height: 16px;
    color: var(--color-blue);
    transition: color var(--transition-fast);
}

.btn-pronunciation:hover .icon {
    color: white;
}

.pronunciation-term {
    font-weight: 500;
}

.pronunciation-lang {
    font-size: 0.75rem;
    color: var(--text-muted);
    padding: 2px 6px;
    background: var(--bg-secondary);
    border-radius: var(--radius-sm);
    margin-left: var(--spacing-xs);
}

.btn-pronunciation:hover .pronunciation-lang {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

/* No audio state */
.btn-pronunciation.no-audio {
    opacity: 0.6;
    cursor: help;
}

.btn-pronunciation.no-audio:hover {
    background: var(--bg-card);
    border-color: var(--border-color);
    color: var(--text-primary);
    transform: none;
}

.btn-pronunciation.no-audio .icon {
    color: var(--text-muted);
}

/* Playing state */
.btn-pronunciation.playing {
    background: var(--color-blue);
    border-color: var(--color-blue);
    color: white;
    animation: pronunciation-pulse 1s ease-in-out infinite;
}

.btn-pronunciation.playing .icon {
    color: white;
    animation: pronunciation-wave 0.5s ease-in-out infinite;
}

@keyframes pronunciation-pulse {
    0%, 100% {
        box-shadow: 0 0 0 0 rgba(59, 130, 246, 0.4);
    }
    50% {
        box-shadow: 0 0 0 8px rgba(59, 130, 246, 0);
    }
}

@keyframes pronunciation-wave {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.2);
    }
}

/* Responsive */
@media (max-width: 640px) {
    .card-terms {
        padding: var(--spacing-sm);
    }

    .card-terms-buttons {
        gap: var(--spacing-xs);
    }

    .btn-pronunciation {
        padding: var(--spacing-xs);
        font-size: 0.85rem;
    }

    .pronunciation-lang {
        display: none;
    }
}

@media (max-width: 480px) {
    .flashcard {
        min-height: 280px;
    }

    .flashcard__inner {
        min-height: 280px;
    }

    .flashcard__front,
    .flashcard__back {
        min-height: 280px;
        padding: var(--spacing-md);
    }

    .flashcard__question {
        font-size: 1.05rem;
    }

    .flashcard__answer {
        font-size: 0.95rem;
    }

    .quality-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-xs);
    }

    .quality-btn {
        padding: var(--spacing-xs);
        font-size: 0.8rem;
    }

    .cards-type-filter {
        gap: var(--spacing-xs);
        padding: var(--spacing-xs);
    }

    .filter-btn {
        padding: var(--spacing-xs) var(--spacing-sm);
        font-size: 0.8rem;
    }
}