/* ============================================
   Knowledge Base Bot — Mini App Styles
   Telegram Web App Compatible
   ============================================ */

/* CSS Variables — Telegram Theme Integration */
:root {
    --tg-theme-bg-color: #ffffff;
    --tg-theme-text-color: #000000;
    --tg-theme-hint-color: #999999;
    --tg-theme-link-color: #2481cc;
    --tg-theme-button-color: #2481cc;
    --tg-theme-button-text-color: #ffffff;
    --tg-theme-secondary-bg-color: #f0f0f0;

    --bg: var(--tg-theme-bg-color);
    --text: var(--tg-theme-text-color);
    --hint: var(--tg-theme-hint-color);
    --link: var(--tg-theme-link-color);
    --btn: var(--tg-theme-button-color);
    --btn-text: var(--tg-theme-button-text-color);
    --secondary-bg: var(--tg-theme-secondary-bg-color);

    --success: #34c759;
    --danger: #ff3b30;
    --warning: #ff9500;
    --info: #5ac8fa;

    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-lg: 0 4px 12px rgba(0,0,0,0.12);
    --transition: 0.2s ease;
}

/* Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen,
        Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
    min-height: 100vh;
}

#app {
    max-width: 600px;
    margin: 0 auto;
    padding-bottom: 20px;
}

/* ============================================
   Screens
   ============================================ */
.screen {
    display: none;
    padding: 16px;
    animation: fadeIn 0.2s ease;
}

.screen.active {
    display: block;
}

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

/* ============================================
   Loading Screen
   ============================================ */
.loader {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 60vh;
    gap: 16px;
}

.spinner {
    width: 36px;
    height: 36px;
    border: 3px solid var(--secondary-bg);
    border-top: 3px solid var(--btn);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.loader p {
    color: var(--hint);
    font-size: 14px;
}

/* ============================================
   Header
   ============================================ */
.header {
    margin-bottom: 16px;
}

.header h1 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 12px;
}

.header h2 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
}

.back-btn {
    background: none;
    border: none;
    color: var(--link);
    font-size: 16px;
    cursor: pointer;
    padding: 4px 0;
    margin-bottom: 8px;
    display: inline-block;
    font-weight: 500;
}

.back-btn:active {
    opacity: 0.6;
}

/* ============================================
   Search Bar
   ============================================ */
.search-bar {
    margin-bottom: 10px;
}

.search-bar input {
    width: 100%;
    padding: 10px 14px;
    border: 2px solid var(--secondary-bg);
    border-radius: var(--radius);
    font-size: 14px;
    background: var(--secondary-bg);
    color: var(--text);
    outline: none;
    transition: border-color var(--transition);
    font-family: inherit;
}

.search-bar input:focus {
    border-color: var(--btn);
    background: var(--bg);
}

.search-bar input::placeholder {
    color: var(--hint);
}

/* ============================================
   Filters
   ============================================ */
.filters {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 4px;
}

.filter-btn {
    background: var(--secondary-bg);
    border: none;
    border-radius: 20px;
    padding: 6px 14px;
    font-size: 13px;
    color: var(--text);
    cursor: pointer;
    white-space: nowrap;
    transition: all var(--transition);
    font-weight: 500;
}

.filter-btn.active {
    background: var(--btn);
    color: var(--btn-text);
}

.filter-btn:active {
    transform: scale(0.95);
}

/* ============================================
   Sessions List
   ============================================ */
.sessions-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.session-card {
    background: var(--secondary-bg);
    border-radius: var(--radius);
    padding: 14px 16px;
    cursor: pointer;
    transition: all var(--transition);
    position: relative;
    border: 2px solid transparent;
}

.session-card:active {
    transform: scale(0.98);
}

.session-card.active {
    border-color: var(--success);
}

.session-card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 6px;
}

.session-id {
    font-weight: 700;
    font-size: 15px;
}

.session-status {
    font-size: 12px;
    padding: 2px 8px;
    border-radius: 10px;
    font-weight: 600;
}

.session-status.active {
    background: rgba(52, 199, 89, 0.15);
    color: var(--success);
}

.session-status.completed {
    background: rgba(153, 153, 153, 0.15);
    color: var(--hint);
}

.session-card-body {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 13px;
    color: var(--hint);
}

.session-type {
    display: flex;
    align-items: center;
    gap: 4px;
}

.session-messages-count {
    display: flex;
    align-items: center;
    gap: 4px;
}

.session-date {
    margin-left: auto;
    font-size: 12px;
}

/* ============================================
   Empty State
   ============================================ */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 40vh;
    text-align: center;
    gap: 8px;
}

.empty-icon {
    font-size: 48px;
    margin-bottom: 8px;
}

.empty-state p {
    font-size: 16px;
    color: var(--text);
    font-weight: 500;
}

.empty-state .hint {
    font-size: 14px;
    color: var(--hint);
    font-weight: 400;
}

/* ============================================
   Session Detail — Full-Screen Layout
   ============================================ */
.session-detail-screen {
    padding: 0 !important;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
}

.session-detail-screen.active {
    display: flex !important;
}

/* Compact header */
.session-detail-header {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 6px 8px;
    background: var(--secondary-bg);
    flex-shrink: 0;
    z-index: 10;
    border-bottom: 1px solid rgba(0,0,0,0.06);
}

.sd-title {
    flex: 1;
    font-size: 16px;
    font-weight: 600;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    margin: 0;
    padding: 0 4px;
}

.sd-header-btn {
    background: none;
    border: none;
    font-size: 18px;
    cursor: pointer;
    padding: 0;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    transition: background var(--transition);
    color: var(--text);
    flex-shrink: 0;
}

.sd-header-btn:active {
    background: rgba(0,0,0,0.08);
}

.sd-back-btn {
    font-size: 20px;
    color: var(--link);
    font-weight: 600;
}

/* Messages: fill remaining space */
.session-detail-screen .messages-list {
    flex: 1;
    max-height: none;
    overflow-y: auto;
    padding: 12px 16px;
    margin-bottom: 0;
}

/* Session info (inside modal) */
.session-info-body {
    text-align: left;
    padding: 4px 0;
}

.session-info-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    font-size: 14px;
    border-bottom: 1px solid rgba(0,0,0,0.05);
}

.session-info-row:last-child {
    border-bottom: none;
}

.session-info-label {
    color: var(--hint);
}

.session-info-value {
    font-weight: 600;
}

/* Modal: wider info variant */
.modal-info {
    max-width: 340px;
    text-align: left;
}

.modal-title {
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 8px;
    text-align: center;
}

/* ============================================
   Messages (Chat Style)
   ============================================ */
.messages-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 16px;
    max-height: 60vh;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    padding: 4px 0;
}

.message {
    max-width: 85%;
    padding: 10px 14px;
    border-radius: var(--radius);
    position: relative;
    word-break: break-word;
}

.message.user {
    background: var(--btn);
    color: var(--btn-text);
    align-self: flex-end;
    border-bottom-right-radius: 4px;
}

.message.assistant {
    background: var(--secondary-bg);
    color: var(--text);
    align-self: flex-start;
    border-bottom-left-radius: 4px;
}

.message-role {
    font-size: 11px;
    font-weight: 700;
    margin-bottom: 4px;
    opacity: 0.7;
    text-transform: uppercase;
}

.message-content {
    font-size: 14px;
    line-height: 1.6;
}

.message-content pre {
    background: rgba(0,0,0,0.08);
    border-radius: var(--radius-sm);
    padding: 8px 12px;
    overflow-x: auto;
    font-size: 13px;
    margin: 8px 0;
}

.message-content code {
    background: rgba(0,0,0,0.06);
    padding: 1px 4px;
    border-radius: 4px;
    font-size: 13px;
}

.message-content pre code {
    background: none;
    padding: 0;
}

.message-content ul, .message-content ol {
    padding-left: 20px;
    margin: 6px 0;
}

.message-content p {
    margin: 4px 0;
}

.message-content h1, .message-content h2, .message-content h3 {
    margin: 8px 0 4px;
}

.message-time {
    font-size: 11px;
    opacity: 0.5;
    margin-top: 4px;
    text-align: right;
}

.message.user .message-content pre {
    background: rgba(255,255,255,0.15);
}

.message.user .message-content code {
    background: rgba(255,255,255,0.2);
}

/* ============================================
   Attachments
   ============================================ */
.attachments-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
    margin-bottom: 8px;
}

.attachment {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 6px 10px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    background: rgba(0,0,0,0.06);
}

.message.user .attachment {
    background: rgba(255,255,255,0.15);
}

.attachment-icon {
    font-size: 18px;
    flex-shrink: 0;
}

.attachment-label {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-weight: 500;
}

.attachment-size {
    font-size: 11px;
    opacity: 0.6;
    white-space: nowrap;
}

.attachment-photo {
    padding: 4px;
    background: none;
}

.attachment-photo-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 60px;
    color: var(--hint);
    font-size: 13px;
    background: rgba(0,0,0,0.04);
    border-radius: var(--radius-sm);
    padding: 8px;
}

.attachment-img {
    max-width: 100%;
    max-height: 300px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: block;
}

.attachment-voice {
    flex-wrap: wrap;
}

.attachment-voice .attachment-audio {
    width: 100%;
    height: 32px;
    margin-top: 4px;
}

/* ============================================
   Bottom Sheet (Actions)
   ============================================ */
.bottom-sheet {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: flex;
    align-items: flex-end;
}

.bottom-sheet.hidden {
    display: none;
}

.bottom-sheet-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0,0,0,0.4);
}

.bottom-sheet-content {
    position: relative;
    background: var(--bg);
    border-radius: var(--radius) var(--radius) 0 0;
    padding: 8px 16px calc(env(safe-area-inset-bottom, 12px) + 12px);
    width: 100%;
    z-index: 1;
    animation: sheetUp 0.25s ease;
}

.bottom-sheet-handle {
    width: 36px;
    height: 4px;
    background: var(--hint);
    opacity: 0.25;
    border-radius: 2px;
    margin: 0 auto 12px;
}

@keyframes sheetUp {
    from { transform: translateY(100%); }
    to { transform: translateY(0); }
}

.session-actions-list {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.action-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 12px;
    border: none;
    background: none;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    border-radius: var(--radius-sm);
    color: var(--text);
    width: 100%;
    text-align: left;
    transition: background var(--transition);
    font-family: inherit;
}

.action-item:active {
    background: var(--secondary-bg);
}

.action-item.danger {
    color: var(--danger);
}

.action-item .action-icon {
    font-size: 20px;
    width: 28px;
    text-align: center;
    flex-shrink: 0;
}

/* ============================================
   Session Actions (legacy btn styles)
   ============================================ */

.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 20px;
    border: none;
    border-radius: var(--radius);
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition);
    width: 100%;
}

.btn:active {
    transform: scale(0.97);
}

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

.btn-secondary {
    background: var(--secondary-bg);
    color: var(--text);
}

.btn-success {
    background: var(--success);
    color: white;
}

.btn-danger {
    background: var(--danger);
    color: white;
}

.btn-warning {
    background: var(--warning);
    color: white;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.btn-row {
    display: flex;
    gap: 8px;
}

.btn-row .btn {
    flex: 1;
}

/* ============================================
   Files Browser
   ============================================ */
.breadcrumb {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    align-items: center;
    padding: 8px 0;
    font-size: 13px;
    color: var(--hint);
}

.breadcrumb-item {
    cursor: pointer;
    color: var(--link);
}

.breadcrumb-item:last-child {
    color: var(--text);
    font-weight: 600;
}

.breadcrumb-separator {
    color: var(--hint);
}

.files-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.file-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: var(--secondary-bg);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition);
}

.file-item:active {
    transform: scale(0.98);
}

.file-icon {
    font-size: 20px;
}

.file-name {
    flex: 1;
    font-size: 14px;
    font-weight: 500;
}

.file-size {
    font-size: 12px;
    color: var(--hint);
}

/* ============================================
   File View
   ============================================ */
.file-content {
    background: var(--secondary-bg);
    border-radius: var(--radius);
    padding: 16px;
    font-size: 14px;
    line-height: 1.7;
    overflow-x: auto;
}

.file-content pre {
    background: rgba(0,0,0,0.06);
    border-radius: var(--radius-sm);
    padding: 12px;
    overflow-x: auto;
    font-size: 13px;
    margin: 10px 0;
}

.file-content code {
    background: rgba(0,0,0,0.04);
    padding: 2px 5px;
    border-radius: 4px;
    font-size: 13px;
}

.file-content pre code {
    background: none;
    padding: 0;
}

.file-content h1 { font-size: 22px; margin: 16px 0 8px; }
.file-content h2 { font-size: 19px; margin: 14px 0 6px; }
.file-content h3 { font-size: 16px; margin: 12px 0 4px; }

.file-content ul, .file-content ol {
    padding-left: 24px;
    margin: 8px 0;
}

.file-content img {
    max-width: 100%;
    border-radius: var(--radius-sm);
}

.file-content blockquote {
    border-left: 3px solid var(--btn);
    padding-left: 12px;
    margin: 8px 0;
    color: var(--hint);
}

.file-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 10px 0;
    font-size: 13px;
}

.file-content th, .file-content td {
    border: 1px solid rgba(0,0,0,0.1);
    padding: 6px 10px;
    text-align: left;
}

.file-content th {
    background: rgba(0,0,0,0.04);
    font-weight: 600;
}

/* ============================================
   Modal
   ============================================ */
.modal {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal.hidden {
    display: none;
}

.modal-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0,0,0,0.4);
}

.modal-content {
    position: relative;
    background: var(--bg);
    border-radius: var(--radius);
    padding: 24px;
    max-width: 300px;
    width: 90%;
    text-align: center;
    box-shadow: var(--shadow-lg);
    z-index: 1;
}

.modal-content p {
    font-size: 15px;
    margin-bottom: 20px;
    font-weight: 500;
}

.modal-actions {
    display: flex;
    gap: 10px;
}

.modal-actions .btn {
    flex: 1;
    padding: 10px;
}

/* ============================================
   Toast
   ============================================ */
.toast-container {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: 8px;
    pointer-events: none;
}

.toast {
    background: var(--text);
    color: var(--bg);
    padding: 10px 20px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
    box-shadow: var(--shadow-lg);
    animation: toastIn 0.3s ease, toastOut 0.3s ease 2.5s forwards;
    white-space: nowrap;
    pointer-events: auto;
}

.toast.success {
    background: var(--success);
    color: white;
}

.toast.error {
    background: var(--danger);
    color: white;
}

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

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

/* ============================================
   Utilities
   ============================================ */
.hidden {
    display: none !important;
}

.text-center {
    text-align: center;
}

.text-hint {
    color: var(--hint);
    font-size: 13px;
}

.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }

/* Skeleton loading */
.skeleton {
    background: linear-gradient(90deg, var(--secondary-bg) 25%, rgba(0,0,0,0.04) 50%, var(--secondary-bg) 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s ease infinite;
    border-radius: var(--radius-sm);
}

@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

.skeleton-card {
    height: 72px;
    border-radius: var(--radius);
    margin-bottom: 10px;
}

.skeleton-message {
    height: 48px;
    margin-bottom: 12px;
    width: 70%;
}

.skeleton-message:nth-child(even) {
    align-self: flex-end;
    width: 60%;
}

/* Scrollbar styling */
::-webkit-scrollbar {
    width: 4px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: rgba(0,0,0,0.15);
    border-radius: 2px;
}