/* =============================================================================
   Variables & Reset
   ============================================================================= */

:root {
    --bg-primary: #0f0f1a;
    --bg-secondary: #1a1a2e;
    --bg-tertiary: #252540;
    --bg-input: #1e1e35;
    --border: #2a2a4a;
    --border-light: #3a3a5a;
    --text-primary: #e0e0e0;
    --text-secondary: #a0a0b8;
    --text-muted: #6a6a8a;
    --accent: #4a7cf7;
    --accent-hover: #5a8cff;
    --accent-dim: rgba(74, 124, 247, 0.15);
    --user-bubble: #2a4a8a;
    --assistant-bubble: #252540;
    --danger: #e74c3c;
    --success: #2ecc71;
    --sidebar-width: 260px;
    --input-bar-height: auto;
    --radius: 12px;
    --radius-sm: 8px;
}

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

html, body {
    height: 100%;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    overflow: hidden;
}

.hidden { display: none !important; }

/* =============================================================================
   Login Screen
   ============================================================================= */

#login-screen {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.login-box {
    background: rgba(255, 255, 255, 0.04);
    border-radius: 16px;
    padding: 48px 40px;
    border: 1px solid var(--border);
    max-width: 400px;
    width: 90%;
    text-align: center;
}

.login-box h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 4px;
}

.login-subtitle {
    color: var(--text-secondary);
    margin-bottom: 32px;
    font-size: 0.95rem;
}

.login-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.login-form input {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    background: var(--bg-input);
    color: var(--text-primary);
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.2s;
}

.login-form input:focus {
    border-color: var(--accent);
}

.login-form button {
    padding: 12px;
    border-radius: var(--radius-sm);
    border: none;
    background: var(--accent);
    color: white;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    margin-top: 8px;
    transition: background 0.2s;
}

.login-form button:hover {
    background: var(--accent-hover);
}

#login-error {
    color: var(--danger);
    font-size: 0.85rem;
    min-height: 20px;
}

/* =============================================================================
   App Layout
   ============================================================================= */

#app {
    display: flex;
    height: 100vh;
    width: 100%;
}

#mobile-header {
    display: none;
}

/* =============================================================================
   Sidebar
   ============================================================================= */

#sidebar {
    width: var(--sidebar-width);
    min-width: var(--sidebar-width);
    background: linear-gradient(180deg, var(--bg-secondary) 0%, #161628 100%);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
}

.sidebar-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 16px 12px;
    border-bottom: 1px solid var(--border);
}

.sidebar-header h1 {
    font-size: 1.25rem;
    font-weight: 700;
}

.sidebar-header button {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    border-radius: var(--radius-sm);
    padding: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s;
}

.sidebar-header button:hover {
    background: var(--border-light);
}

#conversation-list {
    flex: 1;
    overflow-y: auto;
    padding: 8px;
}

.conv-item {
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 0.85rem;
    color: var(--text-secondary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    transition: background 0.15s;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
}

.conv-item:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.conv-item.active {
    background: var(--accent-dim);
    color: var(--text-primary);
}

.conv-item .conv-title {
    overflow: hidden;
    text-overflow: ellipsis;
    flex: 1;
}

.conv-item .conv-delete {
    opacity: 0;
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 2px;
    font-size: 1rem;
    line-height: 1;
    flex-shrink: 0;
    transition: opacity 0.15s, color 0.15s;
}

.conv-item:hover .conv-delete {
    opacity: 1;
}

.conv-item .conv-delete:hover {
    color: var(--danger);
}

.sidebar-section {
    padding: 12px 16px;
    border-top: 1px solid var(--border);
}

.sidebar-section h3 {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--text-muted);
    letter-spacing: 0.05em;
    margin-bottom: 8px;
}

.setting-group {
    margin-bottom: 12px;
}

.setting-group label {
    display: block;
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

.toggle-group {
    display: flex;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.toggle-btn {
    flex: 1;
    padding: 6px 8px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.8rem;
    cursor: pointer;
    transition: all 0.2s;
}

.toggle-btn.active {
    background: var(--accent);
    color: white;
}

.toggle-btn:hover:not(.active) {
    background: var(--bg-tertiary);
}

.source-checkbox {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 4px 0;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.source-checkbox input[type="checkbox"] {
    accent-color: var(--accent);
}

#index-status {
    font-size: 0.8rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

#index-status .status-line {
    display: flex;
    justify-content: space-between;
    padding: 2px 0;
}

#index-status .status-label {
    color: var(--text-muted);
}

#reasoning-status {
    font-size: 0.8rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

#reasoning-status .status-line {
    display: flex;
    justify-content: space-between;
    padding: 2px 0;
}

#reasoning-status .status-label {
    color: var(--text-muted);
}

.status-enabled {
    color: var(--success);
    font-weight: 500;
}

.status-disabled {
    color: var(--text-muted);
}

/* Mode - compact row with hover tooltip */
.mode-row {
    position: relative;
}

.mode-tooltip {
    display: none;
    position: absolute;
    left: 0;
    top: 100%;
    margin-top: 6px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-sm);
    padding: 8px 10px;
    font-size: 0.72rem;
    color: var(--text-secondary);
    line-height: 1.5;
    z-index: 50;
    width: max-content;
    max-width: 280px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    pointer-events: none;
}

.mode-row:hover .mode-tooltip {
    display: block;
}

/* MCP Tools - compact row with hover tooltip */
.mcp-tools-row {
    display: flex;
    align-items: center;
    gap: 8px;
    position: relative;
}

.mcp-tools-row .source-checkbox {
    flex-shrink: 0;
}

.toggle-group-inline {
    flex-shrink: 0;
    min-width: 0;
}

.mcp-tools-tooltip {
    display: none;
    position: absolute;
    left: 0;
    top: 100%;
    margin-top: 6px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-sm);
    padding: 8px 10px;
    font-size: 0.72rem;
    color: var(--text-secondary);
    line-height: 1.5;
    z-index: 50;
    width: max-content;
    max-width: 280px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    pointer-events: none;
}

.mcp-tools-row:hover .mcp-tools-tooltip {
    display: block;
}

.sidebar-footer {
    padding: 12px 16px;
    border-top: 1px solid var(--border);
    margin-top: auto;
}

#user-display {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

#logout-btn {
    width: 100%;
    padding: 8px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.8rem;
    cursor: pointer;
    transition: all 0.2s;
}

#logout-btn:hover {
    background: rgba(231, 76, 60, 0.15);
    border-color: var(--danger);
    color: var(--danger);
}

/* =============================================================================
   Chat Area
   ============================================================================= */

#chat-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100vh;
    min-width: 0;
}

#messages {
    flex: 1;
    overflow-y: auto;
    padding: 24px 16px;
    scroll-behavior: smooth;
}

.message {
    max-width: 800px;
    margin: 0 auto 16px;
    display: flex;
    gap: 12px;
    animation: fadeIn 0.2s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(4px); }
    to { opacity: 1; transform: translateY(0); }
}

.message.user {
    flex-direction: row-reverse;
}

.msg-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 600;
    flex-shrink: 0;
    margin-top: 2px;
}

.message.user .msg-avatar {
    background: var(--accent);
    color: white;
}

.message.assistant .msg-avatar {
    background: var(--bg-tertiary);
    color: var(--accent);
    border: 1px solid var(--border);
}

.msg-content {
    padding: 12px 16px;
    border-radius: var(--radius);
    line-height: 1.6;
    font-size: 0.92rem;
    max-width: calc(100% - 44px);
    overflow-wrap: break-word;
    word-break: break-word;
}

.message.user .msg-content {
    background: var(--user-bubble);
    border-bottom-right-radius: 4px;
}

.message.assistant .msg-content {
    background: var(--assistant-bubble);
    border: 1px solid var(--border);
    border-bottom-left-radius: 4px;
}

/* Markdown styling inside messages */
.msg-content p { margin: 0 0 8px; }
.msg-content p:last-child { margin-bottom: 0; }
.msg-content ul, .msg-content ol { margin: 4px 0 8px 20px; }
.msg-content li { margin-bottom: 4px; }
.msg-content h1, .msg-content h2, .msg-content h3,
.msg-content h4, .msg-content h5, .msg-content h6 {
    margin: 16px 0 8px;
    font-weight: 600;
}
.msg-content h1 { font-size: 1.3em; }
.msg-content h2 { font-size: 1.15em; }
.msg-content h3 { font-size: 1.05em; }

.msg-content code {
    background: rgba(0, 0, 0, 0.3);
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 0.85em;
    font-family: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
}

.msg-content pre {
    margin: 8px 0;
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.msg-content pre code {
    display: block;
    padding: 14px 16px;
    background: #0d1117;
    overflow-x: auto;
    font-size: 0.84em;
    line-height: 1.5;
    border-radius: var(--radius-sm);
}

.msg-content a {
    color: var(--accent);
    text-decoration: none;
}

.msg-content a:hover {
    text-decoration: underline;
}

.msg-content .source-path {
    color: var(--text-secondary);
    background: rgba(74, 124, 247, 0.1);
    padding: 1px 6px;
    border-radius: 4px;
    font-size: 0.85em;
    font-family: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
}

.msg-content blockquote {
    border-left: 3px solid var(--accent);
    padding: 4px 12px;
    margin: 8px 0;
    color: var(--text-secondary);
}

.msg-content table {
    border-collapse: collapse;
    margin: 8px 0;
    font-size: 0.88em;
    width: 100%;
}

.msg-content th, .msg-content td {
    border: 1px solid var(--border);
    padding: 6px 10px;
    text-align: left;
}

.msg-content th {
    background: var(--bg-tertiary);
}

/* Reasoning block */
.msg-content details {
    margin: 8px 0;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.msg-content details summary {
    padding: 8px 12px;
    background: var(--bg-tertiary);
    cursor: pointer;
    font-size: 0.85rem;
    color: var(--text-secondary);
    user-select: none;
}

.msg-content details summary:hover {
    background: var(--border);
}

.msg-content details > .reasoning-body {
    padding: 12px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    background: rgba(0, 0, 0, 0.15);
    white-space: pre-wrap;
    max-height: 300px;
    overflow-y: auto;
}

/* Streaming cursor */
.streaming-cursor::after {
    content: '';
    display: inline-block;
    width: 7px;
    height: 16px;
    background: var(--accent);
    margin-left: 2px;
    vertical-align: text-bottom;
    animation: blink 1s step-end infinite;
}

@keyframes blink {
    50% { opacity: 0; }
}

/* Welcome message */
.welcome-message {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-muted);
    max-width: 500px;
    margin: 0 auto;
}

.welcome-message h2 {
    font-size: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.welcome-message p {
    font-size: 0.9rem;
    line-height: 1.6;
}

/* =============================================================================
   Input Bar
   ============================================================================= */

#input-bar {
    padding: 12px 16px 16px;
    display: flex;
    align-items: flex-end;
    gap: 8px;
    max-width: 832px;
    margin: 0 auto;
    width: 100%;
}

#input-wrapper {
    flex: 1;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 24px;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    transition: border-color 0.2s;
}

#input-wrapper:focus-within {
    border-color: var(--accent);
}

#file-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    padding: 0;
}

#file-chips:not(:empty) {
    padding: 8px 12px 0;
}

.file-chip {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px 8px;
    background: var(--accent-dim);
    border: 1px solid var(--border);
    border-radius: 12px;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.file-chip button {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 1rem;
    line-height: 1;
    padding: 0;
}

.file-chip button:hover {
    color: var(--danger);
}

#message-input {
    width: 100%;
    padding: 12px 16px;
    border: none;
    background: transparent;
    color: var(--text-primary);
    font-size: 0.92rem;
    font-family: inherit;
    resize: none;
    outline: none;
    max-height: 200px;
    line-height: 1.5;
}

#message-input::placeholder {
    color: var(--text-muted);
}

#upload-btn, #send-btn, #stop-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    flex-shrink: 0;
    transition: background 0.2s;
}

#upload-btn {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
}

#upload-btn:hover {
    background: var(--border-light);
    color: var(--text-primary);
}

#send-btn {
    background: var(--accent);
    color: white;
}

#send-btn:hover {
    background: var(--accent-hover);
}

#send-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

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

#stop-btn:hover {
    background: #c0392b;
}

/* =============================================================================
   Scrollbar
   ============================================================================= */

::-webkit-scrollbar {
    width: 6px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--border-light);
}

/* =============================================================================
   Mobile Responsive
   ============================================================================= */

@media (max-width: 768px) {
    #mobile-header {
        display: flex;
        align-items: center;
        gap: 12px;
        padding: 12px 16px;
        background: var(--bg-secondary);
        border-bottom: 1px solid var(--border);
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        z-index: 100;
        height: 52px;
    }

    #sidebar-toggle {
        background: none;
        border: none;
        color: var(--text-primary);
        cursor: pointer;
        padding: 4px;
        display: flex;
    }

    .mobile-title {
        font-weight: 700;
        font-size: 1.1rem;
    }

    #sidebar {
        position: fixed;
        left: 0;
        top: 0;
        bottom: 0;
        z-index: 200;
        transform: translateX(-100%);
        transition: transform 0.25s ease;
    }

    #sidebar.open {
        transform: translateX(0);
    }

    #sidebar-overlay {
        position: fixed;
        inset: 0;
        background: rgba(0, 0, 0, 0.5);
        z-index: 150;
    }

    #chat-area {
        padding-top: 52px;
    }

    #input-bar {
        padding: 8px 12px 12px;
    }

    .message {
        padding: 0 4px;
    }

    .msg-content {
        max-width: calc(100% - 40px);
    }
}