/* ========== CSS变量 - 青色主题 ========== */
:root {
    --tk-primary: #0891b2;
    --tk-primary-hover: #0e7490;
    --tk-primary-light: #e0f2fe;
    --tk-primary-rgb: 8, 145, 178;
    --tk-toolbar-bg: linear-gradient(135deg, #0891b2 0%, #0e7490 100%);
    --tk-toolbar-shadow: rgba(8, 145, 178, 0.35);
    --tk-btn-bg: #ffffff;
    --tk-btn-text: #0e7490;
    --tk-section-bg: #ffffff;
    --tk-border: #e2e8f0;
    --tk-text: #1e293b;
    --tk-text-secondary: #64748b;
    --tk-config-bg: #fafafa;
    --tk-result-bg: #f0f9ff;
    --tk-history-bg: #ffffff;
    --tk-input-bg: #ffffff;
    --tk-input-border: #d1d5db;
    --tk-input-focus: #0891b2;
    --tk-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    --tk-shadow-md: 0 4px 16px rgba(0, 0, 0, 0.1);
    --tk-radius: 8px;
}

/* ========== 暗黑模式变量 ========== */
.tk-dark {
    --tk-primary: #22d3ee;
    --tk-primary-hover: #06b6d4;
    --tk-primary-light: #083344;
    --tk-primary-rgb: 34, 211, 238;
    --tk-toolbar-bg: linear-gradient(135deg, #0c4a6e 0%, #0e7490 100%);
    --tk-toolbar-shadow: rgba(12, 74, 110, 0.5);
    --tk-btn-bg: #334155;
    --tk-btn-text: #22d3ee;
    --tk-section-bg: #1e293b;
    --tk-border: #334155;
    --tk-text: #f1f5f9;
    --tk-text-secondary: #94a3b8;
    --tk-config-bg: #0f172a;
    --tk-result-bg: #051018;
    --tk-history-bg: #1e293b;
    --tk-input-bg: #1e293b;
    --tk-input-border: #475569;
    --tk-input-focus: #22d3ee;
    --tk-shadow: 0 2px 8px rgba(0, 0, 0, 0.4);
    --tk-shadow-md: 0 4px 16px rgba(0, 0, 0, 0.5);
}

/* ========== 主容器 ========== */
.tk-container {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 200px);
    min-height: 600px;
    background: #f8fafc;
    border-radius: var(--tk-radius);
    overflow: hidden;
    box-shadow: var(--tk-shadow);
    transition: box-shadow 0.3s ease, background 0.3s ease;
}

.tk-dark.tk-container,
.tk-dark .tk-container {
    background: #0f172a;
}

.tk-container.tk-fullscreen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw !important;
    height: 100vh !important;
    z-index: 9999;
    border-radius: 0;
    margin: 0;
}

/* ========== 工具栏 ========== */
.tk-toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 14px;
    background: var(--tk-toolbar-bg);
    color: white;
    flex-wrap: wrap;
    gap: 8px;
    box-shadow: 0 2px 10px var(--tk-toolbar-shadow);
    flex-shrink: 0;
    transition: background 0.3s ease;
}

.toolbar-group {
    display: flex;
    gap: 6px;
    align-items: center;
    flex-wrap: wrap;
    min-height: 28px;
}

.toolbar-btn {
    padding: 6px 11px;
    background: var(--tk-btn-bg);
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 12px;
    font-weight: 500;
    color: var(--tk-btn-text);
    transition: transform 0.18s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.18s, opacity 0.18s;
    white-space: nowrap;
}

.toolbar-btn:hover:not(:disabled) { transform: translateY(-1px); box-shadow: 0 4px 10px rgba(0,0,0,0.18); }
.toolbar-btn:active:not(:disabled) { transform: translateY(0); box-shadow: none; }
.toolbar-btn:disabled { opacity: 0.45; cursor: not-allowed; }

/* ========== 主内容区 ========== */
.tk-main-content {
    display: flex;
    flex: 1;
    overflow: hidden;
    background: var(--tk-config-bg);
    transition: background 0.3s ease;
}

/* ========== 左侧历史面板 ========== */
.tk-history-panel {
    width: 200px;
    background: var(--tk-history-bg);
    border-right: 1px solid var(--tk-border);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    flex-shrink: 0;
    transition: background 0.3s ease, border-color 0.3s ease;
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 12px;
    background: linear-gradient(to bottom, #fafafa, #f5f5f5);
    border-bottom: 1px solid var(--tk-border);
    flex-shrink: 0;
    transition: background 0.3s;
}

.tk-dark .history-header {
    background: linear-gradient(to bottom, #1e293b, #162032);
}

.history-header h3 {
    margin: 0;
    font-size: 12px;
    font-weight: 600;
    color: var(--tk-text-secondary);
}

.history-clear-btn {
    background: #fff0f0;
    border: none;
    color: #ef4444;
    font-size: 11px;
    cursor: pointer;
    padding: 2px 6px;
    border-radius: 3px;
    transition: background 0.2s;
}

.history-clear-btn:hover { background: #fde8e8; }
.tk-dark .history-clear-btn { background: rgba(239, 68, 68, 0.15); }

.history-search {
    padding: 6px 8px;
    border-bottom: 1px solid var(--tk-border);
    flex-shrink: 0;
}

.history-search input {
    width: 100%;
    padding: 5px 8px;
    border: 1px solid var(--tk-input-border);
    border-radius: 4px;
    font-size: 11px;
    background: var(--tk-input-bg);
    color: var(--tk-text);
    box-sizing: border-box;
    transition: border-color 0.2s;
}

.history-search input:focus { outline: none; border-color: var(--tk-input-focus); }

.history-list {
    flex: 1;
    overflow-y: auto;
    padding: 4px 0;
}

.history-item {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    padding: 8px 10px;
    cursor: pointer;
    transition: background 0.15s;
    border-left: 2px solid transparent;
    gap: 4px;
}

.history-item:hover { background: var(--tk-primary-light); }
.history-item.current { background: var(--tk-primary-light); border-left-color: var(--tk-primary); }
.tk-dark .history-item:hover { background: rgba(8, 145, 178, 0.12); }
.tk-dark .history-item.current { background: rgba(8, 145, 178, 0.12); }

.history-item-main {
    display: flex;
    align-items: flex-start;
    gap: 5px;
    flex: 1;
    min-width: 0;
}

.history-mode-icon { font-size: 12px; flex-shrink: 0; margin-top: 1px; }

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

.history-item-topic {
    font-size: 11px;
    color: var(--tk-text);
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.history-item-meta {
    font-size: 10px;
    color: var(--tk-text-secondary);
    margin-top: 2px;
}

.history-delete-btn {
    background: none;
    border: none;
    color: #94a3b8;
    cursor: pointer;
    font-size: 14px;
    line-height: 1;
    padding: 0 2px;
    flex-shrink: 0;
    transition: color 0.2s;
}

.history-delete-btn:hover { color: #ef4444; }

.history-empty {
    text-align: center;
    color: var(--tk-text-secondary);
    font-size: 11px;
    padding: 20px 10px;
}

/* ========== 中间配置面板 ========== */
.tk-config-panel {
    width: 310px;
    background: var(--tk-config-bg);
    border-right: 1px solid var(--tk-border);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    flex-shrink: 0;
    padding: 10px;
    transition: background 0.3s, border-color 0.3s;
}

.config-section { margin-bottom: 10px; }

.config-label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
    font-weight: 600;
    color: var(--tk-text-secondary);
    margin-bottom: 5px;
}

.optional-badge {
    font-size: 10px;
    font-weight: 400;
    background: #f1f5f9;
    color: #94a3b8;
    padding: 1px 5px;
    border-radius: 3px;
    margin-left: 4px;
}

.tk-dark .optional-badge { background: #334155; }

.char-count {
    font-size: 10px;
    font-weight: 400;
    color: var(--tk-text-secondary);
    transition: color 0.2s;
}

.char-count.warn { color: #ef4444; }
.char-count.orange { color: #f97316; }
.char-count.ok { color: #10b981; }

/* ========== 导入示例栏 ========== */
.tk-example-bar {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 7px;
}

.tk-example-label {
    font-size: 11.5px;
    color: var(--tk-text-secondary);
    flex-shrink: 0;
}

.tk-example-chip {
    display: inline-flex;
    align-items: center;
    padding: 3px 10px;
    background: var(--tk-primary-light);
    border: 1px solid rgba(var(--tk-primary-rgb), 0.3);
    border-radius: 12px;
    font-size: 11.5px;
    color: var(--tk-primary);
    cursor: pointer;
    user-select: none;
    transition: background 0.18s, border-color 0.18s, transform 0.18s, color 0.18s;
}

.tk-example-chip:hover {
    background: var(--tk-primary);
    color: #ffffff;
    border-color: var(--tk-primary);
    transform: translateY(-1px);
}

.tk-example-chip.ael-active {
    background: var(--tk-primary-hover);
    color: #ffffff;
    border-color: var(--tk-primary-hover);
    transform: scale(0.95);
}

.textarea-wrapper { position: relative; }

.tk-textarea {
    width: 100%;
    padding: 8px 10px;
    border: 1px solid var(--tk-input-border);
    border-radius: var(--tk-radius);
    font-size: 12px;
    line-height: 1.5;
    resize: vertical;
    background: var(--tk-input-bg);
    color: var(--tk-text);
    box-sizing: border-box;
    transition: border-color 0.2s, box-shadow 0.2s;
    font-family: inherit;
}

.tk-textarea:focus {
    outline: none;
    border-color: var(--tk-input-focus);
    box-shadow: 0 0 0 2px rgba(var(--tk-primary-rgb), 0.15);
}

.topic-textarea { min-height: 72px; }
.context-textarea { min-height: 52px; }

.copy-input-btn {
    position: absolute;
    top: 6px;
    right: 6px;
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid var(--tk-input-border);
    border-radius: 4px;
    cursor: pointer;
    font-size: 11px;
    padding: 2px 5px;
    color: var(--tk-text-secondary);
    transition: opacity 0.2s, background 0.2s;
}

.copy-input-btn:hover { background: var(--tk-primary-light); color: var(--tk-primary); }
.copy-input-btn.hidden { display: none; }

/* ========== 思维模式网格 ========== */
.mode-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 5px;
}

.mode-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 7px 3px;
    border: 1.5px solid var(--tk-border);
    border-radius: 7px;
    cursor: pointer;
    background: var(--tk-section-bg);
    transition: border-color 0.2s, background 0.2s, transform 0.15s;
    text-align: center;
    user-select: none;
}

.mode-card:hover { border-color: var(--tk-primary); background: var(--tk-primary-light); transform: translateY(-1px); }
.mode-card.active {
    border-color: var(--tk-primary);
    background: var(--tk-primary-light);
    box-shadow: 0 0 0 2px rgba(var(--tk-primary-rgb), 0.2);
}

.mode-icon { font-size: 16px; line-height: 1; margin-bottom: 2px; }
.mode-name { font-size: 10px; font-weight: 600; color: var(--tk-text); white-space: nowrap; }
.mode-desc { font-size: 9px; color: var(--tk-text-secondary); margin-top: 1px; white-space: nowrap; }

/* ========== 分析深度 ========== */
.depth-group {
    display: flex;
    gap: 6px;
}

.depth-card {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 7px 4px;
    border: 1.5px solid var(--tk-border);
    border-radius: 7px;
    cursor: pointer;
    background: var(--tk-section-bg);
    transition: border-color 0.2s, background 0.2s;
    text-align: center;
    user-select: none;
}

.depth-card:hover { border-color: var(--tk-primary); background: var(--tk-primary-light); }
.depth-card.active {
    border-color: var(--tk-primary);
    background: var(--tk-primary-light);
    box-shadow: 0 0 0 2px rgba(var(--tk-primary-rgb), 0.2);
}

.depth-icon { font-size: 14px; }
.depth-name { font-size: 11px; font-weight: 600; color: var(--tk-text); }
.depth-hint { font-size: 9px; color: var(--tk-text-secondary); }

/* ========== 生成按钮区 ========== */
.generate-section {
    margin-bottom: 8px;
    display: flex;
    gap: 8px;
    align-items: center;
}

.generate-btn {
    flex: 1;
    min-width: 180px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 7px;
    padding: 10px 14px;
    background: var(--tk-toolbar-bg);
    color: white;
    border: none;
    border-radius: var(--tk-radius);
    cursor: pointer;
    font-size: 13px;
    font-weight: 600;
    transition: opacity 0.2s, transform 0.15s, box-shadow 0.15s;
    box-shadow: 0 3px 10px rgba(var(--tk-primary-rgb), 0.3);
}

.generate-btn:hover:not(:disabled) { opacity: 0.92; transform: translateY(-1px); box-shadow: 0 5px 16px rgba(var(--tk-primary-rgb), 0.4); }
.generate-btn:active:not(:disabled) { transform: none; box-shadow: 0 2px 6px rgba(var(--tk-primary-rgb), 0.3); }
.generate-btn:disabled { opacity: 0.6; cursor: not-allowed; transform: none; }

.cancel-btn {
    padding: 9px 12px;
    background: #f1f5f9;
    border: 1px solid var(--tk-border);
    border-radius: var(--tk-radius);
    cursor: pointer;
    font-size: 12px;
    color: #475569;
    transition: background 0.2s;
    white-space: nowrap;
}

.cancel-btn:hover { background: #fee2e2; color: #ef4444; border-color: #fca5a5; }
.cancel-btn.hidden { display: none; }

.btn-spinner {
    width: 14px;
    height: 14px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: tk-spin 0.8s linear infinite;
    flex-shrink: 0;
}

.btn-spinner.hidden { display: none; }

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

.kbd-hint {
    font-size: 10px;
    opacity: 0.75;
    white-space: nowrap;
}

.kbd-hint kbd {
    background: rgba(255, 255, 255, 0.25);
    border-radius: 3px;
    padding: 1px 4px;
    font-size: 10px;
    font-family: inherit;
}

.hint-bar {
    font-size: 11px;
    color: var(--tk-text-secondary);
    padding: 6px 8px;
    background: var(--tk-section-bg);
    border-radius: 5px;
    border: 1px solid var(--tk-border);
    line-height: 1.5;
}

/* ========== 右侧结果面板 ========== */
.tk-result-panel {
    flex: 1;
    background: var(--tk-result-bg);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    min-width: 0;
    transition: background 0.3s;
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 14px;
    background: var(--tk-section-bg);
    border-bottom: 1px solid var(--tk-border);
    flex-shrink: 0;
    gap: 8px;
    flex-wrap: wrap;
    transition: background 0.3s, border-color 0.3s;
}

.result-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--tk-text);
    flex-shrink: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    max-width: 55%;
}

.result-actions {
    display: flex;
    align-items: center;
    gap: 6px;
    flex-wrap: wrap;
}

.result-actions.hidden { display: none; }

.insight-badge {
    background: var(--tk-primary-light);
    color: var(--tk-primary);
    font-size: 11px;
    padding: 2px 8px;
    border-radius: 10px;
    font-weight: 500;
}

.result-btn {
    padding: 4px 9px;
    background: var(--tk-section-bg);
    border: 1px solid var(--tk-border);
    border-radius: 4px;
    cursor: pointer;
    font-size: 11px;
    color: var(--tk-text-secondary);
    transition: background 0.2s, border-color 0.2s, color 0.2s;
    white-space: nowrap;
}

.result-btn:hover { background: var(--tk-primary-light); color: var(--tk-primary); border-color: var(--tk-primary); }

.result-body {
    flex: 1;
    overflow-y: auto;
    padding: 10px;
    gap: 8px;
}

/* ========== 空状态 ========== */
.empty-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    flex: 1;
    padding: 40px 20px;
    text-align: center;
}

.empty-placeholder.hidden { display: none; }
.empty-icon { font-size: 40px; margin-bottom: 12px; opacity: 0.4; }
.empty-text { font-size: 14px; color: var(--tk-text-secondary); font-weight: 500; }
.empty-hint { font-size: 12px; color: var(--tk-text-secondary); margin-top: 6px; opacity: 0.7; }

/* ========== 结果摘要 ========== */
.result-summary {
    background: linear-gradient(135deg, rgba(var(--tk-primary-rgb), 0.1) 0%, rgba(var(--tk-primary-rgb), 0.05) 100%);
    border: 1px solid rgba(var(--tk-primary-rgb), 0.25);
    border-radius: var(--tk-radius);
    padding: 10px 14px;
    font-size: 13px;
    color: var(--tk-text);
    line-height: 1.6;
    font-weight: 500;
}

/* ========== 章节卡片 ========== */
.section-card {
    background: var(--tk-section-bg);
    border-radius: var(--tk-radius);
    border: 1px solid var(--tk-border);
    overflow: hidden;
    transition: box-shadow 0.2s, background 0.3s;
}

.section-card:hover { box-shadow: var(--tk-shadow); }

.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 9px 12px;
    cursor: pointer;
    border-left: 3px solid var(--section-color, var(--tk-primary));
    user-select: none;
    gap: 8px;
    transition: background 0.15s;
}

.section-header:hover { background: rgba(var(--tk-primary-rgb), 0.05); }
.tk-dark .section-header:hover { background: rgba(var(--tk-primary-rgb), 0.1); }

.section-left {
    display: flex;
    align-items: center;
    gap: 7px;
    flex: 1;
    min-width: 0;
}

.section-icon { font-size: 14px; flex-shrink: 0; }

.section-title {
    font-size: 12px;
    font-weight: 600;
    color: var(--tk-text);
}

.section-count {
    font-size: 10px;
    background: var(--tk-primary-light);
    color: var(--tk-primary);
    padding: 1px 6px;
    border-radius: 8px;
    font-weight: 500;
    flex-shrink: 0;
}

.tk-dark .section-count { background: rgba(var(--tk-primary-rgb), 0.2); }

.section-toggle {
    font-size: 12px;
    color: var(--tk-text-secondary);
    transition: transform 0.2s;
    flex-shrink: 0;
}

.section-card.collapsed .section-toggle { transform: rotate(-90deg); }

.section-body { border-top: 1px solid var(--tk-border); }
.section-card.collapsed .section-body { display: none; }

/* ========== 条目行 ========== */
.item-row {
    display: flex;
    align-items: flex-start;
    gap: 8px;
    padding: 7px 12px;
    border-bottom: 1px solid var(--tk-border);
    cursor: pointer;
    transition: background 0.15s;
}

.item-row:last-child { border-bottom: none; }
.item-row:hover { background: rgba(var(--tk-primary-rgb), 0.04); }
.tk-dark .item-row:hover { background: rgba(var(--tk-primary-rgb), 0.08); }

.item-num {
    flex-shrink: 0;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--section-color, var(--tk-primary));
    color: white;
    font-size: 9px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 1px;
}

.item-text {
    flex: 1;
    font-size: 12px;
    color: var(--tk-text);
    line-height: 1.5;
}

.item-copy-btn {
    flex-shrink: 0;
    background: none;
    border: none;
    color: var(--tk-text-secondary);
    cursor: pointer;
    font-size: 12px;
    opacity: 0;
    transition: opacity 0.2s;
    padding: 0 2px;
}

.item-row:hover .item-copy-btn { opacity: 1; }

/* ========== 结论卡片 ========== */
.conclusion-card {
    background: var(--tk-section-bg);
    border-radius: var(--tk-radius);
    border: 1px solid rgba(var(--tk-primary-rgb), 0.3);
    overflow: hidden;
}

.conclusion-header {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 8px 12px;
    background: rgba(var(--tk-primary-rgb), 0.08);
    font-size: 12px;
    font-weight: 600;
    color: var(--tk-primary);
    border-bottom: 1px solid rgba(var(--tk-primary-rgb), 0.2);
}

.conclusion-body {
    padding: 10px 12px;
    font-size: 12px;
    color: var(--tk-text);
    line-height: 1.6;
    cursor: pointer;
    transition: background 0.15s;
}

.conclusion-body:hover { background: rgba(var(--tk-primary-rgb), 0.04); }

/* ========== 延伸思考 ========== */
.questions-card {
    background: var(--tk-section-bg);
    border-radius: var(--tk-radius);
    border: 1px solid var(--tk-border);
    overflow: hidden;
}

.questions-header {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 8px 12px;
    background: linear-gradient(to bottom, #fafafa, #f5f5f5);
    font-size: 12px;
    font-weight: 600;
    color: var(--tk-text-secondary);
    border-bottom: 1px solid var(--tk-border);
}

.tk-dark .questions-header { background: linear-gradient(to bottom, #1e293b, #162032); }

.question-item {
    display: flex;
    align-items: flex-start;
    gap: 6px;
    padding: 7px 12px;
    border-bottom: 1px solid var(--tk-border);
    cursor: pointer;
    transition: background 0.15s;
    font-size: 12px;
    color: var(--tk-text);
    line-height: 1.5;
}

.question-item:last-child { border-bottom: none; }
.question-item:hover { background: var(--tk-primary-light); }
.tk-dark .question-item:hover { background: rgba(var(--tk-primary-rgb), 0.08); }
.question-icon { flex-shrink: 0; font-size: 12px; margin-top: 1px; }

/* ========== 结果加载状态 ========== */
.result-loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    flex: 1;
    min-height: 200px;
    padding: 60px 20px;
    text-align: center;
    gap: 14px;
}

.result-loading-spinner {
    width: 38px;
    height: 38px;
    border: 3px solid rgba(var(--tk-primary-rgb), 0.2);
    border-top-color: var(--tk-primary);
    border-radius: 50%;
    animation: tk-spin 0.85s linear infinite;
}

.result-loading-text {
    font-size: 14px;
    font-weight: 600;
    color: var(--tk-primary);
    letter-spacing: 0.3px;
}

.result-loading-hint {
    font-size: 12px;
    color: var(--tk-text-secondary);
    max-width: 280px;
    line-height: 1.5;
}

/* ========== 生成中禁用模式/深度选择 ========== */
.tk-generating .mode-card,
.tk-generating .depth-card {
    pointer-events: none;
    opacity: 0.5;
    cursor: not-allowed;
}

/* ========== 结果过时提示 ========== */
.stale-hint {
    font-size: 11px;
    color: #f97316;
    background: #fff7ed;
    border: 1px solid #fed7aa;
    border-radius: 4px;
    padding: 2px 8px;
    white-space: nowrap;
    flex-shrink: 0;
    animation: stale-fade-in 0.2s ease;
}

.tk-dark .stale-hint {
    background: rgba(249, 115, 22, 0.12);
    border-color: rgba(249, 115, 22, 0.3);
    color: #fb923c;
}

@keyframes stale-fade-in {
    from { opacity: 0; transform: translateY(-2px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ========== Toast通知 ========== */
.tk-toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    background: #1e293b;
    color: white;
    padding: 9px 18px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
    z-index: 99999;
    opacity: 0;
    transition: opacity 0.25s, transform 0.25s;
    cursor: pointer;
    white-space: nowrap;
    max-width: 90vw;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

.tk-toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
.tk-toast.type-error { background: #dc2626; }
.tk-toast.type-warning { background: #d97706; }
.tk-toast.type-success { background: #059669; }

/* ========== 响应式 ========== */
@media (max-width: 900px) {
    .tk-history-panel { display: none; }
    .tk-config-panel { width: 270px; }
}

@media (max-width: 650px) {
    .tk-main-content { flex-direction: column; }
    .tk-config-panel { width: 100%; border-right: none; border-bottom: 1px solid var(--tk-border); max-height: 60vh; }
    .tk-result-panel { min-height: 300px; }
    .mode-grid { grid-template-columns: repeat(4, 1fr); }
}

@media (max-width: 420px) {
    .mode-grid { grid-template-columns: repeat(2, 1fr); }
    .depth-group { flex-wrap: wrap; }
    .depth-card { flex: 0 0 calc(33% - 4px); }
}