/* ============================================
   全局变量与重置
   ============================================ */
:root {
    --color-primary: #1a5276;
    --color-primary-light: #2980b9;
    --color-primary-dark: #0e3a5f;
    --color-accent: #e67e22;
    --color-accent-light: #f39c12;
    --color-bg: #f0f2f5;
    --color-surface: #ffffff;
    --color-surface-hover: #f8f9fa;
    --color-border: #d5d8dc;
    --color-text: #2c3e50;
    --color-text-secondary: #7f8c8d;
    --color-text-light: #95a5a6;
    --color-user-msg: #2980b9;
    --color-user-msg-bg: #ebf5fb;
    --color-bot-msg: #2c3e50;
    --color-danger: #e74c3c;
    --color-success: #27ae60;
    --color-warning: #f39c12;
    --sidebar-width: 320px;
    --header-height: 60px;
    --input-height: 120px;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.15);
    --transition: 0.3s ease;
}

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

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
                 "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue",
                 Helvetica, Arial, sans-serif;
    background: var(--color-bg);
    color: var(--color-text);
    font-size: 15px;
    line-height: 1.6;
    display: flex;
    flex-direction: column;
}

/* ============================================
   顶部标题栏
   ============================================ */
.app-header {
    height: var(--header-height);
    background: linear-gradient(135deg, var(--color-primary-dark), var(--color-primary));
    color: white;
    display: flex;
    align-items: center;
    padding: 0 20px;
    box-shadow: var(--shadow-md);
    z-index: 100;
    flex-shrink: 0;
}

.header-title {
    display: flex;
    align-items: center;
    gap: 10px;
    flex: 1;
}

.header-title h1 {
    font-size: 20px;
    font-weight: 600;
    letter-spacing: 1px;
}

.header-icon {
    font-size: 24px;
}

.header-status {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    opacity: 0.9;
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--color-danger);
    transition: var(--transition);
}

.status-dot.connected {
    background: var(--color-success);
    box-shadow: 0 0 8px rgba(39, 174, 96, 0.5);
}

.status-dot.loading {
    background: var(--color-warning);
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

.sidebar-toggle {
    display: none;
    background: none;
    border: none;
    color: white;
    cursor: pointer;
    padding: 6px;
    margin-right: 10px;
    border-radius: var(--radius-sm);
    transition: background var(--transition);
}

.sidebar-toggle:hover {
    background: rgba(255,255,255,0.15);
}

/* ============================================
   主体布局
   ============================================ */
.app-body {
    flex: 1;
    display: flex;
    overflow: hidden;
    position: relative;
}

/* ============================================
   左侧设置区
   ============================================ */
.sidebar {
    width: var(--sidebar-width);
    background: var(--color-surface);
    border-right: 1px solid var(--color-border);
    overflow-y: auto;
    flex-shrink: 0;
    transition: transform var(--transition);
}

.sidebar-content {
    padding: 20px;
}

.setting-section {
    margin-bottom: 24px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--color-border);
}

.setting-section:last-child {
    border-bottom: none;
}

.setting-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 14px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--color-text-secondary);
    margin-bottom: 6px;
}

.form-group input[type="text"],
.form-group input[type="password"],
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-family: inherit;
    background: var(--color-surface);
    color: var(--color-text);
    transition: border-color var(--transition), box-shadow var(--transition);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-primary-light);
    box-shadow: 0 0 0 3px rgba(41, 128, 185, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 80px;
    line-height: 1.5;
}

.form-group input[type="range"] {
    width: 100%;
    height: 6px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--color-border);
    border-radius: 3px;
    outline: none;
}

.form-group input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--color-primary-light);
    cursor: pointer;
    border: 2px solid white;
    box-shadow: var(--shadow-sm);
}

.form-group input[type="range"]::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--color-primary-light);
    cursor: pointer;
    border: 2px solid white;
    box-shadow: var(--shadow-sm);
}

.form-group input[type="checkbox"] {
    margin-right: 6px;
    width: 16px;
    height: 16px;
    cursor: pointer;
    accent-color: var(--color-primary-light);
    vertical-align: middle;
}

.form-group label[for="thinkingToggle"] {
    cursor: pointer;
    display: flex;
    align-items: center;
    font-size: 14px;
    color: var(--color-text);
}

.form-hint {
    font-size: 12px;
    color: var(--color-text-light);
    margin-top: 4px;
}

.form-hint a {
    color: var(--color-primary-light);
    text-decoration: none;
}

.form-hint a:hover {
    text-decoration: underline;
}

.value-badge {
    display: inline-block;
    background: var(--color-primary-light);
    color: white;
    font-size: 12px;
    padding: 1px 8px;
    border-radius: 10px;
    margin-left: 6px;
}

.input-with-action {
    position: relative;
    display: flex;
    align-items: center;
}

.input-with-action input {
    padding-right: 40px;
}

.toggle-btn {
    position: absolute;
    right: 8px;
    background: none;
    border: none;
    cursor: pointer;
    color: var(--color-text-secondary);
    padding: 4px;
    display: flex;
    align-items: center;
}

.toggle-btn:hover {
    color: var(--color-primary-light);
}

/* 快捷提问按钮 */
.quick-prompts {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.quick-prompt-btn {
    text-align: left;
    padding: 10px 14px;
    background: var(--color-surface-hover);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 13px;
    color: var(--color-text);
    cursor: pointer;
    transition: all var(--transition);
    font-family: inherit;
}

.quick-prompt-btn:hover {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
    transform: translateX(2px);
}

/* 对话管理按钮 */
.conversation-actions {
    display: flex;
    gap: 8px;
    margin-bottom: 12px;
}

.action-btn {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition);
    background: var(--color-surface);
    color: var(--color-text);
    font-family: inherit;
}

.action-btn.primary {
    background: var(--color-primary-light);
    color: white;
    border-color: var(--color-primary-light);
}

.action-btn.primary:hover {
    background: var(--color-primary);
    border-color: var(--color-primary);
}

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

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

.conversation-stats {
    display: flex;
    gap: 16px;
    font-size: 12px;
    color: var(--color-text-secondary);
    padding: 8px 0;
}

.stat-item strong {
    color: var(--color-primary);
}

/* 遮罩层 */
.overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.4);
    z-index: 99;
}

.overlay.active {
    display: block;
}

/* ============================================
   中间对话区
   ============================================ */
.chat-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: var(--color-bg);
}

.messages-container {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    scroll-behavior: smooth;
}

.messages-container::-webkit-scrollbar {
    width: 6px;
}

.messages-container::-webkit-scrollbar-track {
    background: transparent;
}

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

.messages-container::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-light);
}

/* ============================================
   欢迎屏幕
   ============================================ */
.welcome-screen {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100%;
    text-align: center;
    padding: 40px 20px;
}

.welcome-icon {
    font-size: 64px;
    margin-bottom: 16px;
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.welcome-screen h2 {
    font-size: 28px;
    color: var(--color-primary);
    margin-bottom: 8px;
}

.welcome-screen > p {
    color: var(--color-text-secondary);
    font-size: 16px;
    margin-bottom: 32px;
}

.feature-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 16px;
    max-width: 700px;
    width: 100%;
    margin-bottom: 32px;
}

.feature-card {
    background: var(--color-surface);
    border-radius: var(--radius-md);
    padding: 20px 16px;
    box-shadow: var(--shadow-sm);
    transition: transform var(--transition), box-shadow var(--transition);
    border: 1px solid var(--color-border);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    font-size: 32px;
    margin-bottom: 10px;
}

.feature-card h3 {
    font-size: 15px;
    color: var(--color-primary);
    margin-bottom: 6px;
}

.feature-card p {
    font-size: 13px;
    color: var(--color-text-secondary);
    line-height: 1.4;
}

.welcome-tip {
    background: rgba(41, 128, 185, 0.1);
    border: 1px solid rgba(41, 128, 185, 0.2);
    border-radius: var(--radius-md);
    padding: 12px 24px;
    font-size: 14px;
    color: var(--color-primary);
}

/* ============================================
   消息气泡
   ============================================ */
.message {
    display: flex;
    gap: 12px;
    margin-bottom: 20px;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
    animation: fadeInUp 0.4s ease;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.message-avatar {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    color: white;
    font-weight: 600;
}

.message.user .message-avatar {
    background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
}

.message.assistant .message-avatar {
    background: linear-gradient(135deg, var(--color-accent), var(--color-accent-light));
}

.message-body {
    flex: 1;
    min-width: 0;
}

.message-content {
    padding: 14px 18px;
    border-radius: var(--radius-md);
    font-size: 15px;
    line-height: 1.7;
    word-break: break-word;
    overflow-wrap: break-word;
}

.message.user .message-content {
    background: var(--color-user-msg-bg);
    color: var(--color-user-msg);
    border: 1px solid rgba(41, 128, 185, 0.15);
}

.message.assistant .message-content {
    background: var(--color-surface);
    color: var(--color-bot-msg);
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-sm);
}

.message-meta {
    font-size: 12px;
    color: var(--color-text-light);
    margin-top: 4px;
    padding: 0 6px;
    display: flex;
    align-items: center;
    gap: 12px;
}

/* ============================================
   Markdown 内容渲染样式
   ============================================ */
.message-content h1,
.message-content h2,
.message-content h3,
.message-content h4 {
    margin: 16px 0 8px;
    color: var(--color-primary);
    font-weight: 600;
}

.message-content h1 { font-size: 22px; }
.message-content h2 { font-size: 19px; }
.message-content h3 { font-size: 16px; }
.message-content h4 { font-size: 15px; }

.message-content p {
    margin: 8px 0;
}

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

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

.message-content code {
    background: rgba(0,0,0,0.06);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: "SF Mono", "Fira Code", "Consolas", monospace;
    font-size: 0.9em;
}

.message-content pre {
    background: #1e1e2e;
    color: #cdd6f4;
    padding: 14px;
    border-radius: var(--radius-sm);
    overflow-x: auto;
    margin: 10px 0;
    font-size: 13px;
    line-height: 1.5;
}

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

.message-content blockquote {
    border-left: 3px solid var(--color-primary-light);
    padding-left: 14px;
    margin: 10px 0;
    color: var(--color-text-secondary);
}

.message-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 10px 0;
    font-size: 14px;
}

.message-content th,
.message-content td {
    border: 1px solid var(--color-border);
    padding: 8px 12px;
    text-align: left;
}

.message-content th {
    background: var(--color-surface-hover);
    font-weight: 600;
    color: var(--color-primary);
}

.message-content strong {
    font-weight: 600;
    color: var(--color-text);
}

/* KaTeX 公式样式微调 */
.message-content .katex-display {
    margin: 12px 0;
    overflow-x: auto;
    overflow-y: hidden;
    padding: 4px 0;
}

/* ============================================
   思考过程折叠块
   ============================================ */
.thinking-block {
    background: rgba(230, 126, 34, 0.06);
    border: 1px solid rgba(230, 126, 34, 0.2);
    border-radius: var(--radius-sm);
    margin-bottom: 10px;
    overflow: hidden;
}

.thinking-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    cursor: pointer;
    user-select: none;
    font-size: 13px;
    color: var(--color-accent);
    font-weight: 500;
}

.thinking-header:hover {
    background: rgba(230, 126, 34, 0.08);
}

.thinking-icon {
    font-size: 16px;
}

.thinking-title {
    flex: 1;
}

.thinking-toggle {
    transition: transform var(--transition);
    font-size: 10px;
}

.thinking-block.collapsed .thinking-toggle {
    transform: rotate(-90deg);
}

.thinking-content {
    padding: 0 14px 12px;
    font-size: 13px;
    color: var(--color-text-secondary);
    line-height: 1.6;
    white-space: pre-wrap;
    max-height: 300px;
    overflow-y: auto;
}

.thinking-block.collapsed .thinking-content {
    display: none;
}

/* ============================================
   加载动画
   ============================================ */
.typing-indicator {
    display: flex;
    gap: 4px;
    padding: 4px 0;
}

.typing-indicator span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--color-text-light);
    animation: typing 1.4s infinite;
}

.typing-indicator span:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-indicator span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%, 60%, 100% { transform: translateY(0); opacity: 0.4; }
    30% { transform: translateY(-8px); opacity: 1; }
}

/* ============================================
   底部输入区
   ============================================ */
.input-area {
    padding: 12px 20px 16px;
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    flex-shrink: 0;
}

.input-wrapper {
    display: flex;
    align-items: flex-end;
    gap: 10px;
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 8px 8px 8px 14px;
    transition: border-color var(--transition), box-shadow var(--transition);
}

.input-wrapper:focus-within {
    border-color: var(--color-primary-light);
    box-shadow: 0 0 0 3px rgba(41, 128, 185, 0.1);
}

.input-wrapper textarea {
    flex: 1;
    border: none;
    background: none;
    outline: none;
    resize: none;
    font-size: 15px;
    font-family: inherit;
    line-height: 1.5;
    max-height: 120px;
    color: var(--color-text);
    padding: 4px 0;
}

.send-btn {
    width: 40px;
    height: 40px;
    border: none;
    border-radius: 50%;
    background: var(--color-primary-light);
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition);
    flex-shrink: 0;
}

.send-btn:hover:not(:disabled) {
    background: var(--color-primary);
    transform: scale(1.05);
}

.send-btn:active:not(:disabled) {
    transform: scale(0.95);
}

.send-btn:disabled {
    background: var(--color-border);
    cursor: not-allowed;
    opacity: 0.6;
}

.send-btn.loading {
    background: var(--color-warning);
    cursor: wait;
}

.input-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 8px;
    padding: 0 4px;
}

.char-count {
    font-size: 12px;
    color: var(--color-text-light);
}

.model-badge {
    font-size: 12px;
    color: var(--color-primary);
    background: rgba(41, 128, 185, 0.1);
    padding: 2px 10px;
    border-radius: 10px;
    font-family: monospace;
}

/* ============================================
   错误消息
   ============================================ */
.message-content.error-msg {
    background: #fdf2f2 !important;
    border-color: #f5c6cb !important;
    color: #721c24 !important;
}

.message-content.error-msg::before {
    content: "❌ ";
}

/* ============================================
   响应式 - 平板
   ============================================ */
@media (max-width: 1024px) {
    :root {
        --sidebar-width: 280px;
    }

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

/* ============================================
   响应式 - 手机
   ============================================ */
@media (max-width: 768px) {
    :root {
        --header-height: 54px;
    }

    .sidebar-toggle {
        display: flex;
        align-items: center;
    }

    .header-title h1 {
        font-size: 17px;
    }

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

    .header-status .status-text {
        display: none;
    }

    .sidebar {
        position: fixed;
        top: var(--header-height);
        left: 0;
        bottom: 0;
        width: 85%;
        max-width: 320px;
        z-index: 100;
        transform: translateX(-100%);
        box-shadow: var(--shadow-lg);
    }

    .sidebar.active {
        transform: translateX(0);
    }

    .messages-container {
        padding: 14px;
    }

    .message {
        gap: 8px;
    }

    .message-avatar {
        width: 32px;
        height: 32px;
        font-size: 15px;
    }

    .message-content {
        padding: 12px 14px;
        font-size: 14px;
    }

    .feature-cards {
        grid-template-columns: 1fr;
    }

    .welcome-screen h2 {
        font-size: 22px;
    }

    .welcome-screen > p {
        font-size: 14px;
    }

    .input-area {
        padding: 10px 12px 12px;
    }

    .input-wrapper textarea {
        font-size: 14px;
    }

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

/* ============================================
   响应式 - 小屏手机
   ============================================ */
@media (max-width: 420px) {
    .header-title h1 {
        font-size: 15px;
    }

    .welcome-icon {
        font-size: 48px;
    }

    .welcome-screen h2 {
        font-size: 20px;
    }
}