/* ============================================================ */
/* FILE: css/conversation.css - STYLES CHO TAB CONVERSATION     */
/* Teacher Mode - Prefix: conv-* để tránh trùng CSS cũ          */
/* ============================================================ */

/* ============================================================ */
/* ===== CONTAINER CHÍNH ===== */
/* ============================================================ */

#conversationPanel {
    padding: 0.5rem 0;
}

.conv-container {
    max-width: 900px;
    margin: 0 auto;
}

/* ============================================================ */
/* ===== SETUP SCREEN ===== */
/* ============================================================ */

.conv-setup {
    background: var(--bg-secondary);
    border-radius: 28px;
    padding: 2rem 2rem 1.5rem 2rem;
    border: 1px solid var(--border);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
}

.conv-setup h3 {
    text-align: center;
    margin-bottom: 0.5rem;
    font-size: 1.4rem;
    color: var(--text-primary);
}

.conv-intro {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
    line-height: 1.5;
}

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

.conv-form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
}

.conv-topic-input {
    width: 100%;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 0.9rem 1.2rem;
    border-radius: 60px;
    outline: none;
    font-size: 0.95rem;
    transition: all 0.2s;
}

.conv-topic-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.conv-topic-input::placeholder {
    color: var(--text-secondary);
    opacity: 0.5;
}

/* ===== LEVEL SELECTOR ===== */

.conv-level-selector {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 0.5rem;
}

.conv-level-btn {
    background: var(--bg-primary);
    border: 2px solid var(--border);
    color: var(--text-secondary);
    padding: 0.6rem 1rem;
    border-radius: 16px;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
    transition: all 0.2s ease;
    flex: 1;
    min-width: 60px;
    text-align: center;
}

.conv-level-btn:hover {
    border-color: var(--accent);
    color: var(--text-primary);
    transform: translateY(-2px);
}

.conv-level-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: white;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.conv-level-name {
    text-align: center;
    font-size: 0.8rem;
    color: var(--accent);
    margin-top: 0.5rem;
    font-weight: 500;
    opacity: 0.8;
}

/* ===== EXAMPLE CHIPS ===== */

.conv-examples {
    margin-bottom: 1.5rem;
}

.conv-examples-title {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    opacity: 0.8;
}

.conv-example-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.conv-chip {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 0.4rem 0.8rem;
    border-radius: 60px;
    cursor: pointer;
    font-size: 0.75rem;
    transition: all 0.15s ease;
    user-select: none;
}

.conv-chip:hover {
    background: var(--bg-card);
    border-color: var(--accent);
    color: var(--text-primary);
    transform: translateY(-1px);
}

/* ===== START BUTTON ===== */

.conv-start-btn {
    width: 100%;
    background: var(--accent);
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: 60px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s ease;
    letter-spacing: 0.3px;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.conv-start-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
}

.conv-start-btn:active {
    transform: translateY(0);
}

.conv-history-btn-wrap {
    text-align: center;
    margin-top: 1rem;
}

.conv-history-btn {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 0.5rem 1.2rem;
    border-radius: 60px;
    cursor: pointer;
    font-size: 0.8rem;
    transition: all 0.2s ease;
}

.conv-history-btn:hover {
    background: var(--bg-primary);
    border-color: var(--accent);
    color: var(--text-primary);
}

/* ============================================================ */
/* ===== CHAT SCREEN ===== */
/* ============================================================ */

.conv-chat-wrap {
    background: var(--bg-secondary);
    border-radius: 28px;
    border: 1px solid var(--border);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
    height: 75vh;
    max-height: 750px;
    overflow: hidden;
}

/* ===== HEADER ===== */

.conv-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.8rem 1.2rem;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    gap: 0.8rem;
    flex-wrap: wrap;
}

.conv-header-left {
    flex: 1;
    min-width: 0;
}

.conv-topic-label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
    display: block;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.conv-header-right {
    display: flex;
    gap: 0.5rem;
    align-items: center;
    flex-shrink: 0;
}

.conv-level-badge {
    background: var(--bg-card);
    padding: 0.2rem 0.6rem;
    border-radius: 20px;
    font-size: 0.7rem;
    color: var(--warning);
}

.conv-turns-badge {
    background: var(--accent);
    color: white;
    padding: 0.2rem 0.6rem;
    border-radius: 20px;
    font-size: 0.7rem;
    font-weight: 600;
}

/* ===== CHAT BOX ===== */

.conv-chat-box {
    flex: 1;
    overflow-y: auto;
    padding: 1.2rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    scroll-behavior: smooth;
}

.conv-chat-box::-webkit-scrollbar {
    width: 6px;
}

.conv-chat-box::-webkit-scrollbar-track {
    background: var(--bg-primary);
    border-radius: 10px;
}

.conv-chat-box::-webkit-scrollbar-thumb {
    background: var(--bg-card);
    border-radius: 10px;
}

.conv-chat-box::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
}

/* ===== MESSAGE ===== */

.conv-message {
    display: flex;
    gap: 0.6rem;
    max-width: 85%;
    animation: convFadeIn 0.3s ease;
}

.conv-message.conv-ai {
    align-self: flex-start;
}

.conv-message.conv-user {
    align-self: flex-end;
    flex-direction: row;
}

.conv-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    flex-shrink: 0;
    background: var(--bg-primary);
    border: 1px solid var(--border);
}

.conv-message.conv-ai .conv-avatar {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.2), rgba(59, 130, 246, 0.1));
    border-color: rgba(59, 130, 246, 0.3);
}

.conv-message.conv-user .conv-avatar {
    background: linear-gradient(135deg, rgba(34, 197, 94, 0.2), rgba(34, 197, 94, 0.1));
    border-color: rgba(34, 197, 94, 0.3);
}

.conv-bubble {
    background: var(--bg-primary);
    border-radius: 18px;
    padding: 0.8rem 1rem;
    border: 1px solid var(--border);
    min-width: 0;
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.conv-message.conv-ai .conv-bubble {
    border-top-left-radius: 4px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.08), rgba(59, 130, 246, 0.03));
}

.conv-message.conv-user .conv-bubble {
    border-top-right-radius: 4px;
    background: linear-gradient(135deg, rgba(34, 197, 94, 0.08), rgba(34, 197, 94, 0.03));
}

/* ===== QUESTION (AI) ===== */

.conv-question-en {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-primary);
    line-height: 1.5;
    padding-bottom: 0.4rem;
}

/* ===== SUB BUTTONS ===== */

.conv-sub-btns {
    display: flex;
    gap: 0.4rem;
    margin-top: 0.6rem;
    flex-wrap: wrap;
}

.conv-sub-btn {
    background: var(--bg-card);
    border: 1px solid transparent;
    color: var(--text-secondary);
    padding: 0.25rem 0.7rem;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.7rem;
    transition: all 0.15s ease;
}

.conv-sub-btn:hover {
    background: var(--bg-primary);
    border-color: var(--accent);
    color: var(--text-primary);
}

.conv-sub-btn.active {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
}

/* ===== AI ACTIONS (bottom of bubble) ===== */

.conv-ai-actions {
    margin-top: 0.6rem;
    padding-top: 0.6rem;
    border-top: 1px dashed var(--border);
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    align-items: center;
}

.conv-speak-btn-lg {
    background: linear-gradient(135deg, var(--accent), #6366f1);
    color: white;
    border: none;
    padding: 0.5rem 1.4rem;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.82rem;
    font-weight: 600;
    transition: all 0.2s ease;
    letter-spacing: 0.3px;
    box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.conv-speak-btn-lg:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.conv-speak-btn-lg:active {
    transform: translateY(0);
}

.conv-toggle-row {
    display: flex;
    gap: 0.35rem;
    flex-wrap: wrap;
    justify-content: center;
}

/* ===== SUBTITLES ===== */

.conv-sub-vi,
.conv-sub-en {
    margin-top: 0.5rem;
    padding: 0.5rem 0.8rem;
    border-radius: 12px;
    font-size: 0.85rem;
    line-height: 1.5;
    animation: convFadeIn 0.25s ease;
}

.conv-sub-vi {
    background: rgba(245, 158, 11, 0.1);
    border-left: 3px solid var(--warning);
    color: var(--text-primary);
}

.conv-sub-en {
    background: rgba(59, 130, 246, 0.1);
    border-left: 3px solid var(--accent);
    color: var(--text-primary);
    font-style: italic;
}

/* ============================================================ */
/* ===== HINTS (GỢI Ý TRẢ LỜI) ===== */
/* ============================================================ */

.conv-hints {
    margin-top: 0.7rem;
    padding: 0.6rem 0.8rem;
    background: rgba(34, 197, 94, 0.05);
    border-radius: 12px;
    border-left: 3px solid var(--success);
    animation: convFadeIn 0.3s ease;
}

.conv-hints-title {
    font-size: 0.75rem;
    color: var(--success);
    font-weight: 600;
    margin-bottom: 0.4rem;
}

.conv-hints-list {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.conv-hint-item {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 0.35rem 0.7rem;
    border-radius: 10px;
    cursor: pointer;
    font-size: 0.78rem;
    text-align: left;
    transition: all 0.15s ease;
    font-family: inherit;
    line-height: 1.4;
}

.conv-hint-item:hover {
    background: var(--bg-card);
    border-color: var(--success);
    color: var(--text-primary);
    transform: translateX(3px);
}

/* ===== HINT TOGGLE ===== */

.conv-hint-toggle {
    margin-top: 0.5rem;
}

/* ===== USER TEXT ===== */

.conv-user-text {
    font-size: 0.95rem;
    color: var(--text-primary);
    line-height: 1.5;
}

/* ============================================================ */
/* ===== FEEDBACK (4 PHẦN) ===== */
/* ============================================================ */

.conv-feedback {
    margin-top: 0.8rem;
    padding-top: 0.8rem;
    border-top: 1px solid var(--border);
    font-size: 0.85rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

/* 1. Praise */
.conv-praise {
    color: var(--success);
    font-weight: 500;
    line-height: 1.5;
    padding: 0.4rem 0.6rem;
    background: rgba(34, 197, 94, 0.08);
    border-radius: 10px;
    border-left: 3px solid var(--success);
}

/* 2. Grammar */
.conv-grammar {
    color: var(--warning);
    line-height: 1.5;
    padding: 0.4rem 0.6rem;
    background: rgba(245, 158, 11, 0.08);
    border-radius: 10px;
    border-left: 3px solid var(--warning);
}

/* 3. Better version */
.conv-better {
    color: var(--text-primary);
    line-height: 1.5;
    padding: 0.4rem 0.6rem;
    background: rgba(59, 130, 246, 0.08);
    border-radius: 10px;
    border-left: 3px solid var(--accent);
}

.conv-better strong {
    color: var(--accent);
    font-weight: 600;
    font-style: italic;
}

/* 4. Tip */
.conv-tip {
    color: var(--text-primary);
    line-height: 1.5;
    padding: 0.4rem 0.6rem;
    background: rgba(168, 85, 247, 0.08);
    border-radius: 10px;
    border-left: 3px solid #a855f7;
}

/* 5. New words */
.conv-new-words {
    background: var(--bg-secondary);
    padding: 0.5rem 0.8rem;
    border-radius: 10px;
    border-left: 3px solid var(--success);
}

.conv-new-words-title {
    font-size: 0.78rem;
    color: var(--success);
    font-weight: 600;
    margin-bottom: 0.3rem;
}

.conv-new-words ul {
    margin: 0;
    padding-left: 1.1rem;
    list-style: none;
}

.conv-new-words li {
    padding: 0.15rem 0;
    color: var(--text-primary);
    font-size: 0.82rem;
    position: relative;
    line-height: 1.5;
}

.conv-new-words li::before {
    content: '•';
    color: var(--success);
    font-weight: 700;
    position: absolute;
    left: -0.8rem;
}

.conv-new-words li strong {
    color: var(--success);
    font-weight: 600;
}

/* ============================================================ */
/* ===== PROGRESS SUMMARY (giữa chat) ===== */
/* ============================================================ */

.conv-progress-summary {
    align-self: center;
    max-width: 90%;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(168, 85, 247, 0.05));
    border: 1px solid rgba(59, 130, 246, 0.3);
    border-radius: 18px;
    padding: 1rem 1.2rem;
    margin: 0.5rem 0;
    animation: convFadeIn 0.4s ease;
    text-align: left;
}

.conv-progress-title {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: 0.6rem;
    text-align: center;
}

.conv-progress-item {
    font-size: 0.82rem;
    color: var(--text-primary);
    padding: 0.25rem 0;
    line-height: 1.5;
    word-break: break-word;
}

.conv-progress-footer {
    margin-top: 0.6rem;
    padding-top: 0.6rem;
    border-top: 1px dashed rgba(59, 130, 246, 0.3);
    font-size: 0.8rem;
    color: var(--text-secondary);
    text-align: center;
    font-weight: 500;
}

/* ============================================================ */
/* ===== LOADING ===== */
/* ============================================================ */

.conv-loading {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    padding: 0.8rem;
    background: var(--bg-primary);
    border-radius: 16px;
    color: var(--text-secondary);
    font-size: 0.85rem;
    align-self: center;
    border: 1px solid var(--border);
}

.conv-spinner {
    width: 16px;
    height: 16px;
    border: 2px solid var(--bg-card);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: convSpin 0.8s linear infinite;
}

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

/* ===== ERROR ===== */

.conv-error {
    align-self: center;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    border-left: 3px solid var(--danger);
    color: var(--danger);
    padding: 0.6rem 1rem;
    border-radius: 12px;
    font-size: 0.85rem;
    max-width: 90%;
    text-align: center;
}

/* ============================================================ */
/* ===== INPUT AREA ===== */
/* ============================================================ */

.conv-input-wrap {
    display: flex;
    gap: 0.6rem;
    padding: 0.8rem 1.2rem;
    background: var(--bg-primary);
    border-top: 1px solid var(--border);
    align-items: flex-end;
}

.conv-answer-input {
    flex: 1;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 0.7rem 1rem;
    border-radius: 16px;
    outline: none;
    font-size: 0.9rem;
    font-family: inherit;
    resize: none;
    transition: all 0.2s;
    line-height: 1.5;
    min-height: 44px;
    max-height: 120px;
}

.conv-answer-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.conv-answer-input:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.conv-send-btn {
    background: var(--accent);
    color: white;
    border: none;
    padding: 0.7rem 1.3rem;
    border-radius: 16px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    flex-shrink: 0;
    height: 44px;
}

.conv-send-btn:hover:not(:disabled) {
    background: var(--accent-hover);
    transform: translateY(-1px);
}

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

/* ===== ACTIONS ===== */

.conv-actions {
    display: flex;
    gap: 0.6rem;
    padding: 0.6rem 1.2rem 0.8rem 1.2rem;
    background: var(--bg-primary);
    border-top: 1px solid var(--border);
    justify-content: center;
    flex-wrap: wrap;
}

.conv-action-btn {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 0.5rem 1.2rem;
    border-radius: 60px;
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: 500;
    transition: all 0.15s ease;
}

.conv-action-btn:hover {
    background: var(--bg-card);
    border-color: var(--accent);
    color: var(--text-primary);
    transform: translateY(-1px);
}

.conv-action-danger {
    border-color: rgba(239, 68, 68, 0.3);
    color: var(--danger);
}

.conv-action-danger:hover {
    background: rgba(239, 68, 68, 0.1);
    border-color: var(--danger);
    color: var(--danger);
}

/* ============================================================ */
/* ===== SUMMARY SCREEN ===== */
/* ============================================================ */

.conv-summary {
    background: var(--bg-secondary);
    border-radius: 28px;
    padding: 2rem;
    border: 1px solid var(--border);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
    text-align: center;
}

.conv-summary-icon {
    font-size: 4rem;
    margin-bottom: 0.5rem;
    animation: convBounce 0.6s ease;
}

@keyframes convBounce {
    0% { transform: scale(0.5); opacity: 0; }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); opacity: 1; }
}

.conv-summary h3 {
    font-size: 1.6rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.conv-summary-message {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-weight: 500;
    padding: 0.5rem 1rem;
    background: var(--bg-primary);
    border-radius: 12px;
    display: inline-block;
}

.conv-summary-info {
    background: var(--bg-primary);
    border-radius: 20px;
    padding: 1rem 1.5rem;
    margin-bottom: 1.5rem;
    text-align: left;
}

.conv-summary-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0;
    font-size: 0.9rem;
    gap: 1rem;
}

.conv-summary-row + .conv-summary-row {
    border-top: 1px solid var(--border);
}

.conv-summary-row span {
    color: var(--text-secondary);
    flex-shrink: 0;
}

.conv-summary-row strong {
    color: var(--text-primary);
    text-align: right;
    word-break: break-word;
}

.conv-summary-section {
    text-align: left;
    margin-bottom: 1.5rem;
}

.conv-summary-section h4 {
    font-size: 1rem;
    color: var(--accent);
    margin-bottom: 0.8rem;
    font-weight: 600;
}

.conv-summary-words-list {
    list-style: none;
    padding: 0.8rem 1rem;
    margin: 0;
    background: var(--bg-primary);
    border-radius: 16px;
    max-height: 250px;
    overflow-y: auto;
}

.conv-summary-words-list li {
    padding: 0.4rem 0;
    font-size: 0.85rem;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border);
    line-height: 1.5;
}

.conv-summary-words-list li:last-child {
    border-bottom: none;
}

.conv-summary-words-list li strong {
    color: var(--success);
    font-weight: 600;
}

.conv-summary-turns {
    background: var(--bg-primary);
    border-radius: 16px;
    padding: 0.8rem 1rem;
    max-height: 400px;
    overflow-y: auto;
}

.conv-summary-turn {
    display: flex;
    gap: 0.5rem;
    padding: 0.4rem 0;
    font-size: 0.82rem;
    line-height: 1.5;
    align-items: flex-start;
    border-bottom: 1px dashed var(--border);
}

.conv-summary-turn:last-child {
    border-bottom: none;
}

.conv-summary-turn-icon {
    flex-shrink: 0;
    font-size: 0.9rem;
}

.conv-summary-turn-text {
    color: var(--text-secondary);
    word-break: break-word;
}

.conv-empty-note {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.85rem;
    opacity: 0.6;
    padding: 1rem;
    font-style: italic;
}

/* ============================================================ */
/* ===== HISTORY MODAL ===== */
/* ============================================================ */

.conv-history-content {
    max-height: 85vh;
    display: flex;
    flex-direction: column;
}

.conv-history-list {
    max-height: 60vh;
    overflow-y: auto;
    margin: 1rem 0;
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
    padding-right: 0.3rem;
}

.conv-history-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    padding: 0.8rem 1rem;
    background: var(--bg-primary);
    border-radius: 16px;
    border: 1px solid var(--border);
    transition: all 0.15s ease;
    flex-wrap: wrap;
}

.conv-history-item:hover {
    border-color: var(--accent);
    transform: translateX(2px);
}

.conv-history-item-main {
    flex: 1;
    min-width: 0;
}

.conv-history-item-topic {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.3rem;
    overflow: hidden;
    text-overflow: ellipsis;
}

.conv-history-item-meta {
    display: flex;
    gap: 0.8rem;
    flex-wrap: wrap;
    font-size: 0.72rem;
    color: var(--text-secondary);
    opacity: 0.8;
}

.conv-history-item-actions {
    display: flex;
    gap: 0.4rem;
    flex-shrink: 0;
}

.conv-history-btn-sm {
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 0.35rem 0.7rem;
    border-radius: 10px;
    cursor: pointer;
    font-size: 0.72rem;
    transition: all 0.15s ease;
}

.conv-history-btn-sm:hover {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
}

.conv-history-btn-sm.conv-btn-danger {
    color: var(--danger);
}

.conv-history-btn-sm.conv-btn-danger:hover {
    background: var(--danger);
    color: white;
    border-color: var(--danger);
}

/* ===== SESSION VIEW (chi tiết) ===== */

.conv-session-turns {
    max-height: 60vh;
    overflow-y: auto;
    padding-right: 0.3rem;
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
    margin-bottom: 1rem;
}

.conv-session-turn {
    padding: 0.7rem 1rem;
    border-radius: 14px;
    border: 1px solid var(--border);
    background: var(--bg-primary);
}

.conv-session-turn.ai {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.08), rgba(59, 130, 246, 0.03));
    border-left: 3px solid var(--accent);
}

.conv-session-turn.user {
    background: linear-gradient(135deg, rgba(34, 197, 94, 0.08), rgba(34, 197, 94, 0.03));
    border-left: 3px solid var(--success);
}

.conv-session-turn-head {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.3rem;
    opacity: 0.8;
}

.conv-session-turn-text {
    font-size: 0.88rem;
    color: var(--text-primary);
    line-height: 1.5;
    word-break: break-word;
}

.conv-session-turn-vi {
    margin-top: 0.4rem;
    font-size: 0.8rem;
    color: var(--warning);
    font-style: italic;
}

.conv-session-feedback {
    margin-top: 0.6rem;
    padding-top: 0.6rem;
    border-top: 1px dashed var(--border);
    font-size: 0.8rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.conv-session-feedback strong {
    color: var(--success);
    font-weight: 600;
}

/* ============================================================ */
/* ===== ANIMATIONS ===== */
/* ============================================================ */

@keyframes convFadeIn {
    from {
        opacity: 0;
        transform: translateY(8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

@media (max-width: 768px) {
    .conv-setup,
    .conv-summary {
        padding: 1.2rem;
        border-radius: 20px;
    }

    .conv-setup h3 {
        font-size: 1.2rem;
    }

    .conv-intro {
        font-size: 0.85rem;
    }

    .conv-level-btn {
        padding: 0.5rem 0.6rem;
        font-size: 0.75rem;
        min-width: 50px;
    }

    .conv-chip {
        font-size: 0.7rem;
        padding: 0.35rem 0.7rem;
    }

    .conv-start-btn {
        font-size: 0.9rem;
        padding: 0.9rem 1.5rem;
    }

    /* Chat */
    .conv-chat-wrap {
        height: 78vh;
        border-radius: 20px;
    }

    .conv-header {
        padding: 0.6rem 0.8rem;
    }

    .conv-topic-label {
        font-size: 0.82rem;
    }

    .conv-chat-box {
        padding: 0.8rem;
        gap: 0.8rem;
    }

    .conv-message {
        max-width: 92%;
    }

    .conv-avatar {
        width: 30px;
        height: 30px;
        font-size: 1rem;
    }

    .conv-bubble {
        padding: 0.65rem 0.85rem;
        border-radius: 15px;
    }

    .conv-question-en {
        font-size: 0.88rem;
    }

    .conv-user-text {
        font-size: 0.88rem;
    }

    .conv-sub-btn {
        font-size: 0.65rem;
        padding: 0.2rem 0.55rem;
    }

    .conv-sub-vi,
    .conv-sub-en {
        font-size: 0.78rem;
        padding: 0.4rem 0.65rem;
    }

    .conv-ai-actions {
        margin-top: 0.5rem;
        padding-top: 0.5rem;
    }

    .conv-speak-btn-lg {
        font-size: 0.75rem;
        padding: 0.4rem 1.1rem;
    }

    .conv-toggle-row {
        gap: 0.25rem;
    }

    .conv-hints {
        padding: 0.5rem 0.6rem;
    }

    .conv-hints-title {
        font-size: 0.7rem;
    }

    .conv-hint-item {
        font-size: 0.72rem;
        padding: 0.3rem 0.6rem;
    }

    .conv-feedback {
        font-size: 0.78rem;
    }

    .conv-praise,
    .conv-grammar,
    .conv-better,
    .conv-tip {
        font-size: 0.78rem;
        padding: 0.35rem 0.5rem;
    }

    .conv-new-words {
        padding: 0.4rem 0.6rem;
    }

    .conv-new-words-title {
        font-size: 0.72rem;
    }

    .conv-new-words li {
        font-size: 0.75rem;
    }

    .conv-progress-summary {
        padding: 0.8rem 1rem;
    }

    .conv-progress-title {
        font-size: 0.78rem;
    }

    .conv-progress-item {
        font-size: 0.75rem;
    }

    .conv-progress-footer {
        font-size: 0.72rem;
    }

    .conv-input-wrap {
        padding: 0.6rem 0.8rem;
        gap: 0.4rem;
    }

    .conv-answer-input {
        font-size: 0.85rem;
        padding: 0.6rem 0.8rem;
        min-height: 40px;
    }

    .conv-send-btn {
        padding: 0.6rem 1rem;
        font-size: 0.82rem;
        height: 40px;
    }

    .conv-actions {
        padding: 0.5rem 0.8rem 0.7rem 0.8rem;
        gap: 0.4rem;
    }

    .conv-action-btn {
        font-size: 0.72rem;
        padding: 0.4rem 0.9rem;
    }

    /* Summary */
    .conv-summary h3 {
        font-size: 1.3rem;
    }

    .conv-summary-icon {
        font-size: 3rem;
    }

    .conv-summary-message {
        font-size: 0.85rem;
    }

    .conv-summary-info {
        padding: 0.8rem 1rem;
    }

    .conv-summary-row {
        font-size: 0.82rem;
    }

    /* History */
    .conv-history-item {
        padding: 0.6rem 0.8rem;
    }

    .conv-history-item-topic {
        font-size: 0.82rem;
    }

    .conv-history-item-meta {
        font-size: 0.65rem;
        gap: 0.5rem;
    }

    .conv-history-btn-sm {
        font-size: 0.65rem;
        padding: 0.3rem 0.6rem;
    }

    /* Session view */
    .conv-session-turn {
        padding: 0.6rem 0.8rem;
    }

    .conv-session-turn-text {
        font-size: 0.82rem;
    }
}

@media (max-width: 480px) {
    .conv-level-selector {
        gap: 0.3rem;
    }

    .conv-level-btn {
        padding: 0.4rem 0.5rem;
        font-size: 0.7rem;
        min-width: 44px;
    }

    .conv-example-chips {
        gap: 0.3rem;
    }

    .conv-chip {
        font-size: 0.65rem;
        padding: 0.3rem 0.6rem;
    }

    .conv-message {
        max-width: 95%;
    }

    .conv-avatar {
        width: 26px;
        height: 26px;
        font-size: 0.9rem;
    }

    .conv-header-right {
        gap: 0.3rem;
    }

    .conv-level-badge,
    .conv-turns-badge {
        font-size: 0.65rem;
        padding: 0.15rem 0.5rem;
    }
}

/* ============================================================ */
/* ===== SCROLLBAR CHO HISTORY/SESSION ===== */
/* ============================================================ */

.conv-history-list::-webkit-scrollbar,
.conv-session-turns::-webkit-scrollbar,
.conv-summary-words-list::-webkit-scrollbar,
.conv-summary-turns::-webkit-scrollbar {
    width: 6px;
}

.conv-history-list::-webkit-scrollbar-track,
.conv-session-turns::-webkit-scrollbar-track,
.conv-summary-words-list::-webkit-scrollbar-track,
.conv-summary-turns::-webkit-scrollbar-track {
    background: var(--bg-primary);
    border-radius: 10px;
}

.conv-history-list::-webkit-scrollbar-thumb,
.conv-session-turns::-webkit-scrollbar-thumb,
.conv-summary-words-list::-webkit-scrollbar-thumb,
.conv-summary-turns::-webkit-scrollbar-thumb {
    background: var(--bg-card);
    border-radius: 10px;
}

.conv-history-list::-webkit-scrollbar-thumb:hover,
.conv-session-turns::-webkit-scrollbar-thumb:hover,
.conv-summary-words-list::-webkit-scrollbar-thumb:hover,
.conv-summary-turns::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
}