:root {
    --bg: #f5f6fa;
    --surface: #ffffff;
    --primary: #4f6ef7;
    --primary-dark: #3b55d9;
    --text: #2d3748;
    --text-secondary: #718096;
    --border: #e2e8f0;
    --success: #48bb78;
    --warning: #ed8936;
    --danger: #f56565;
    --info: #4299e1;
    --radius: 10px;
    --shadow: 0 1px 3px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.06);
    --shadow-lg: 0 10px 25px rgba(0,0,0,.1);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg); color: var(--text); min-height: 100vh;
}

/* Layout */
.app-header {
    background: var(--surface); border-bottom: 1px solid var(--border);
    padding: 16px 28px; display: flex; align-items: center; gap: 16px;
    position: sticky; top: 0; z-index: 100; box-shadow: var(--shadow);
}
.app-header h1 {
    font-size: 20px; font-weight: 700;
    background: linear-gradient(135deg, var(--primary), #8b5cf6);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
}
.app-header .subtitle { font-size: 13px; color: var(--text-secondary); -webkit-text-fill-color: var(--text-secondary); }
.header-actions { margin-left: auto; display: flex; align-items: center; gap: 12px; }

.container { max-width: 1440px; margin: 0 auto; padding: 20px 24px; }

/* Upload Area */
.upload-zone {
    background: var(--surface); border: 2px dashed var(--border);
    border-radius: var(--radius); padding: 48px 24px;
    text-align: center; transition: all .2s; cursor: pointer;
}
.upload-zone:hover, .upload-zone.dragover {
    border-color: var(--primary); background: #f7f8ff;
}
.upload-zone .icon { font-size: 48px; color: var(--primary); margin-bottom: 12px; }
.upload-zone h2 { font-size: 18px; margin-bottom: 8px; }
.upload-zone p { color: var(--text-secondary); font-size: 14px; }
.upload-zone input { display: none; }
.upload-zone .file-info { margin-top: 16px; padding: 12px 20px; background: #f0f4ff; border-radius: 8px; display: inline-block; font-size: 14px; color: var(--primary); font-weight: 500; }
.upload-zone.uploaded { display: none; }

/* Toolbar */
.toolbar {
    background: var(--surface); border-radius: var(--radius); box-shadow: var(--shadow);
    padding: 16px 20px; margin-bottom: 16px;
    display: flex; flex-wrap: wrap; align-items: center; gap: 12px;
}
.toolbar .filter-group { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.toolbar label { font-size: 13px; font-weight: 600; color: var(--text-secondary); white-space: nowrap; }
.toolbar input, .toolbar select {
    border: 1px solid var(--border); border-radius: 6px; padding: 6px 12px;
    font-size: 13px; background: #fff; color: var(--text); outline: none; min-width: 100px;
}
.toolbar input:focus, .toolbar select:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(79,110,247,.15); }
.toolbar .stat-badge {
    margin-left: auto; display: flex; gap: 16px; font-size: 13px;
}
.toolbar .stat-badge span { padding: 4px 12px; background: var(--bg); border-radius: 20px; white-space: nowrap; }
.toolbar .stat-badge .num { font-weight: 700; color: var(--primary); }

/* Tabs */
.tabs { display: flex; gap: 4px; margin-bottom: 16px; }
.tab-btn {
    padding: 10px 24px; border: none; background: var(--surface); border-radius: 8px 8px 0 0;
    font-size: 14px; font-weight: 600; color: var(--text-secondary); cursor: pointer; transition: all .15s;
    box-shadow: var(--shadow); border-bottom: 2px solid transparent;
}
.tab-btn:hover { color: var(--text); }
.tab-btn.active { color: var(--primary); border-bottom-color: var(--primary); background: var(--surface); }

.tab-content { display: none; }
.tab-content.active { display: block; }

/* Table */
.table-wrap {
    background: var(--surface); border-radius: var(--radius); box-shadow: var(--shadow);
    overflow-x: auto; max-height: calc(100vh - 320px); overflow-y: auto;
}
.table-wrap table { width: 100%; border-collapse: collapse; font-size: 13px; min-width: 900px; }
.table-wrap thead { position: sticky; top: 0; z-index: 10; }
.table-wrap th {
    background: #f8f9fc; padding: 10px 14px; text-align: left; font-weight: 600;
    font-size: 12px; text-transform: uppercase; letter-spacing: .05em; color: var(--text-secondary);
    border-bottom: 2px solid var(--border); white-space: nowrap; cursor: pointer; user-select: none;
}
.table-wrap th:hover { color: var(--primary); }
.table-wrap th .sort-icon { margin-left: 4px; opacity: .4; }
.table-wrap th.sorted .sort-icon { opacity: 1; color: var(--primary); }
.table-wrap td {
    padding: 8px 14px; border-bottom: 1px solid var(--border); vertical-align: middle;
    max-width: 350px; text-overflow: ellipsis; white-space: nowrap;
}
.table-wrap tr:hover td { background: #f8f9ff; }

.status-badge {
    display: inline-block; padding: 2px 8px; border-radius: 12px; font-weight: 600; font-size: 12px;
}
.status-2xx { background: #c6f6d5; color: #22543d; }
.status-3xx { background: #bee3f8; color: #2a4365; }
.status-4xx { background: #fefcbf; color: #744210; }
.status-5xx { background: #fed7d7; color: #742a2a; }
.status-other { background: #e2e8f0; color: #4a5568; }

.method-badge {
    display: inline-block; padding: 2px 6px; border-radius: 4px; font-weight: 700; font-size: 11px;
    min-width: 40px; text-align: center;
}
.method-GET { background: #c6f6d5; color: #22543d; }
.method-POST { background: #bee3f8; color: #2a4365; }
.method-PUT { background: #fefcbf; color: #744210; }
.method-DELETE { background: #fed7d7; color: #742a2a; }
.method-PATCH { background: #e9d8fd; color: #553c9a; }
.method-OPTIONS { background: #e2e8f0; color: #4a5568; }

.url-copy { flex-shrink: 0; font-size: 14px; cursor: pointer; opacity: 0; transition: opacity .15s; color: var(--text-secondary); padding: 2px; border-radius: 4px; line-height: 1; }
.url-copy:hover { opacity: 1 !important; background: #e2e8f0; }

/* Report */
.report-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin-bottom: 24px;
}
.report-card {
    background: var(--surface); border-radius: var(--radius); box-shadow: var(--shadow);
    padding: 20px; text-align: center;
}
.report-card .label { font-size: 12px; text-transform: uppercase; letter-spacing: .05em; color: var(--text-secondary); margin-bottom: 8px; }
.report-card .value { font-size: 28px; font-weight: 700; }
.report-card .sub { font-size: 12px; color: var(--text-secondary); margin-top: 4px; }
.report-card.accent1 .value { color: var(--primary); }
.report-card.accent2 .value { color: var(--success); }
.report-card.accent3 .value { color: var(--warning); }
.report-card.accent4 .value { color: var(--danger); }
.report-card.accent5 .value { color: var(--info); }

.report-section {
    background: var(--surface); border-radius: var(--radius); box-shadow: var(--shadow);
    padding: 20px; margin-bottom: 16px;
}
.report-section h3 { font-size: 15px; margin-bottom: 16px; display: flex; align-items: center; gap: 8px; }
.report-section h3 .count { font-size: 12px; color: var(--text-secondary); font-weight: 400; }

.report-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.report-table th { text-align: left; padding: 8px 12px; font-weight: 600; color: var(--text-secondary); font-size: 12px; border-bottom: 2px solid var(--border); }
.report-table td { padding: 8px 12px; border-bottom: 1px solid var(--border); }
.report-table tr:hover td { background: #f8f9ff; }

.bar-chart { margin-top: 8px; }
.bar-row { display: flex; align-items: center; gap: 8px; margin-bottom: 6px; }
.bar-row .bar-label { width: 400px; font-size: 13px; text-align: left; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; flex-shrink: 0; font-family: monospace; }
.bar-row .bar-track { flex: 1; height: 20px; min-width: 60px; background: #e2e8f0; border-radius: 4px; overflow: hidden; }
.bar-row .bar-fill { height: 100%; border-radius: 4px; background: linear-gradient(90deg, var(--primary), #8b5cf6); transition: width .5s; }
.bar-row .bar-val { width: 80px; font-size: 13px; font-weight: 700; color: var(--text); text-align: right; flex-shrink: 0; }

.stat-distribution { display: flex; gap: 4px; height: 24px; border-radius: 6px; overflow: hidden; margin-top: 8px; }
.stat-distribution .seg { display: flex; align-items: center; justify-content: center; font-size: 11px; font-weight: 700; color: #fff; transition: width .5s; min-width: fit-content; padding: 0 4px; }

/* Status code distribution bar */
.dist-bar { display: flex; height: 32px; border-radius: 8px; overflow: hidden; margin: 8px 0 4px; }
.dist-bar .seg { display: flex; align-items: center; justify-content: center; font-size: 11px; font-weight: 700; color: #fff; transition: width .5s; min-width: 28px; }

/* Spinner */
.spinner { display: none; width: 20px; height: 20px; border: 2px solid var(--border); border-top-color: var(--primary); border-radius: 50%; animation: spin .6s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* Empty state */
.empty-state { text-align: center; padding: 60px 20px; color: var(--text-secondary); }
.empty-state .emoji { font-size: 48px; margin-bottom: 12px; }
.empty-state p { font-size: 15px; }

/* Modal */
.modal-overlay { display: none; position: fixed; inset: 0; background: rgba(0,0,0,.4); z-index: 200; align-items: center; justify-content: center; }
.modal-overlay.show { display: flex; }
.modal {
    background: var(--surface); border-radius: 12px; box-shadow: var(--shadow-lg);
    max-width: 800px; width: 90%; max-height: 80vh; overflow-y: auto; padding: 28px;
}
.modal h3 { font-size: 16px; margin-bottom: 12px; }
.modal .close-btn {
    float: right; border: none; background: none; font-size: 20px; cursor: pointer; color: var(--text-secondary);
}
.modal .close-btn:hover { color: var(--text); }
.modal pre { background: #1a202c; color: #e2e8f0; padding: 16px; border-radius: 8px; font-size: 12px; overflow-x: auto; max-height: 400px; overflow-y: auto; white-space: pre-wrap; word-break: break-all; }

.meta-row { display: flex; gap: 24px; font-size: 13px; margin-bottom: 16px; flex-wrap: wrap; }
.meta-row .meta-item { color: var(--text-secondary); }
.meta-row .meta-item strong { color: var(--text); }

/* Responsive */
@media (max-width: 768px) {
    .container { padding: 12px; }
    .toolbar { flex-direction: column; align-items: stretch; }
    .toolbar .filter-group { flex-wrap: wrap; }
    .toolbar .stat-badge { margin-left: 0; flex-wrap: wrap; }
    .report-grid { grid-template-columns: repeat(2, 1fr); }
    .bar-row .bar-label { width: 180px; }
    .app-header { flex-wrap: wrap; }
    .header-actions { margin-left: 0; width: 100%; }
}

/* scrollbar */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #cbd5e0; border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #a0aec0; }

/* export button */
.btn {
    padding: 8px 16px; border-radius: 6px; border: none; font-size: 13px; font-weight: 600;
    cursor: pointer; transition: all .15s; display: inline-flex; align-items: center; gap: 6px;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }
.btn-sm { padding: 4px 10px; font-size: 12px; }
.btn:disabled { opacity: .5; cursor: not-allowed; }

/* =============================================
   ENHANCED REPORT STYLES
   ============================================= */

/* Badge / Tag */
.badge {
    display: inline-block; padding: 1px 8px; border-radius: 10px; font-size: 11px;
    font-weight: 600; white-space: nowrap;
}
.badge-success { background: #c6f6d5; color: #22543d; }
.badge-warning { background: #fefcbf; color: #744210; }
.badge-danger { background: #fed7d7; color: #742a2a; }
.badge-info { background: #bee3f8; color: #2a4365; }
.badge-muted { background: #e2e8f0; color: #4a5568; }

/* Text colors */
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger { color: var(--danger); }
.text-muted { color: var(--text-secondary); }
.text-bold { font-weight: 700; }

/* Section summary line */
.section-summary {
    font-size: 12px; color: var(--text-secondary); margin: -12px 0 16px; padding-bottom: 8px;
    border-bottom: 1px solid var(--border);
}

/* Waterfall breakdown inside bars */
.waterfall-row {
    display: flex; align-items: center; gap: 8px; margin-bottom: 4px; font-size: 12px;
}
.waterfall-row .bar-label {
    width: 60px; flex-shrink: 0; text-align: right; font-size: 11px; color: var(--text-secondary);
}
.waterfall-row .bar-track {
    flex: 1; height: 16px; background: #edf2f7; border-radius: 3px; overflow: hidden; display: flex;
}
.waterfall-row .bar-seg {
    height: 100%; min-width: 2px; transition: width .3s;
}
.waterfall-seg-blocked { background: #a0aec0; }
.waterfall-seg-dns { background: #68d391; }
.waterfall-seg-connect { background: #f6ad55; }
.waterfall-seg-ssl { background: #fc8181; }
.waterfall-seg-send { background: #63b3ed; }
.waterfall-seg-wait { background: #805ad5; }
.waterfall-seg-receive { background: #48bb78; }
.waterfall-row .bar-val { width: 55px; flex-shrink: 0; text-align: right; font-size: 11px; font-weight: 600; }

/* Resource type icon/tag */
.resource-tag {
    display: inline-block; padding: 1px 6px; border-radius: 4px; font-size: 11px; font-weight: 600;
}
.resource-tag-html { background: #e2e8f0; color: #4a5568; }
.resource-tag-js { background: #fefcbf; color: #744210; }
.resource-tag-css { background: #bee3f8; color: #2a4365; }
.resource-tag-image { background: #c6f6d5; color: #22543d; }
.resource-tag-font { background: #e9d8fd; color: #553c9a; }
.resource-tag-json { background: #fed7d7; color: #742a2a; }
.resource-tag-media { background: #f6e05e; color: #744210; }
.resource-tag-other { background: #e2e8f0; color: #4a5568; }

/* Suggestion cards */
.suggestion-list { list-style: none; padding: 0; }
.suggestion-item {
    padding: 12px 16px; margin-bottom: 8px; border-radius: 8px;
    border-left: 4px solid var(--primary); background: #f7f8ff;
    font-size: 13px; line-height: 1.5;
}
.suggestion-item .suggestion-icon { margin-right: 6px; }
.suggestion-item .suggestion-detail { color: var(--text-secondary); font-size: 12px; margin-top: 4px; }
.suggestion-item.severity-high { border-left-color: var(--danger); background: #fff5f5; }
.suggestion-item.severity-medium { border-left-color: var(--warning); background: #fffff0; }
.suggestion-item.severity-low { border-left-color: var(--info); background: #f0f8ff; }

/* Cache status */
.cache-status { display: inline-block; padding: 1px 8px; border-radius: 10px; font-size: 11px; font-weight: 600; }
.cache-hit { background: #c6f6d5; color: #22543d; }
.cache-negotiated { background: #bee3f8; color: #2a4365; }
.cache-miss { background: #fed7d7; color: #742a2a; }
.cache-unknown { background: #e2e8f0; color: #4a5568; }

/* Sensitive flag */
.sensitive-flag {
    display: inline-block; padding: 0 5px; border-radius: 3px;
    background: #fed7d7; color: #742a2a; font-size: 10px; font-weight: 700;
    margin-right: 4px; cursor: help;
}

/* Collapsible section */
.collapsible-header {
    cursor: pointer; user-select: none;
}
.collapsible-header:hover { opacity: .7; }
.collapsible-header .arrow { display: inline-block; transition: transform .2s; margin-right: 6px; }
.collapsible-header.collapsed .arrow { transform: rotate(-90deg); }
.collapsible-body { overflow: hidden; transition: max-height .3s; }
.collapsible-body.collapsed { max-height: 0 !important; }

/* Percentile mini chart */
.pct-row { display: flex; align-items: center; gap: 10px; margin-bottom: 4px; font-size: 12px; }
.pct-row .pct-label { width: 40px; font-weight: 700; color: var(--text-secondary); flex-shrink: 0; }
.pct-row .pct-track { flex: 1; height: 12px; background: #edf2f7; border-radius: 6px; overflow: hidden; }
.pct-row .pct-fill { height: 100%; border-radius: 6px; transition: width .5s; }
.pct-row .pct-val { width: 70px; text-align: right; font-weight: 600; flex-shrink: 0; }

/* Responsive additions */
@media (max-width: 768px) {
    .waterfall-row { flex-wrap: wrap; }
    .waterfall-row .bar-label { width: 100%; text-align: left; }
    .waterfall-row .bar-val { width: 100%; text-align: left; }
    .suggestion-item { font-size: 12px; }
}

/* Waterfall detail modal override */
.waterfall-detailed { margin-top: 12px; }
.waterfall-detailed .wf-row {
    display: flex; align-items: center; gap: 8px; padding: 4px 0; font-size: 12px;
    border-bottom: 1px solid var(--border);
}
.waterfall-detailed .wf-row:last-child { border-bottom: none; }
.waterfall-detailed .wf-label { width: 120px; flex-shrink: 0; color: var(--text-secondary); }
.waterfall-detailed .wf-track { flex: 1; height: 14px; background: #edf2f7; border-radius: 3px; overflow: hidden; }
.waterfall-detailed .wf-fill { height: 100%; border-radius: 3px; }
.waterfall-detailed .wf-val { width: 70px; text-align: right; font-weight: 600; flex-shrink: 0; }

/* Detail modal tabs */
.detail-tab-btn.active {
    color: var(--primary) !important;
    border-bottom-color: var(--primary) !important;
}
.detail-tab-btn:hover {
    color: var(--text) !important;
}
.detail-tab-content { display: none; }
.detail-tab-content.active { display: block; }

/* Response JSON pretty print */
.response-json {
    background: #1a1a2e;
    color: #e2e8f0;
    padding: 16px;
    border-radius: 8px;
    font-size: 12px;
    line-height: 1.5;
    overflow-x: auto;
    max-height: 60vh;
    white-space: pre-wrap;
    word-break: break-all;
}
.response-json .json-key { color: #63b3ed; }
.response-json .json-string { color: #68d391; }
.response-json .json-number { color: #f6ad55; }
.response-json .json-bool { color: #fc8181; }
.response-json .json-null { color: #a0aec0; }

/* HAR export help - step cards */
.har-help {
    margin: 28px auto 0;
    max-width: 720px;
    padding: 0 4px;
}
.har-help-header {
    font-size: 15px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 18px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--border);
}
.har-steps {
    display: flex;
    flex-direction: column;
    gap: 20px;
}
.har-step {
    display: flex;
    gap: 16px;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 20px;
    box-shadow: var(--shadow);
}
.har-step-num {
    flex-shrink: 0;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    font-size: 15px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
}
.har-step-body { flex: 1; min-width: 0; }
.har-step-title {
    font-size: 15px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 6px;
}
.har-step-desc {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 12px;
}
.har-step-body img {
    max-width: 100%;
    border-radius: 8px;
    border: 1px solid var(--border);
    display: block;
}
/* Image click-to-zoom */
.img-zoom {
    position: relative;
    display: inline-block;
    max-width: 100%;
    cursor: zoom-in;
    border-radius: 8px;
    overflow: hidden;
}
.img-zoom:hover img { filter: brightness(0.85); }
.img-zoom-hint {
    position: absolute;
    bottom: 10px;
    right: 10px;
    background: rgba(0,0,0,.55);
    color: #fff;
    font-size: 11px;
    padding: 3px 10px;
    border-radius: 4px;
    pointer-events: none;
    opacity: 0;
    transition: opacity .2s;
}
.img-zoom:hover .img-zoom-hint { opacity: 1; }

/* ============================================================
   PRINT STYLES — Export PDF (无页脚页眉)
   ============================================================ */
@page { margin: 0; }
@media print {
    /* 隐藏不需要打印的元素 */
    .app-header,
    #uploadZone,
    #reuploadBtn,
    #exportBtn,
    .spinner,
    .tabs,
    #tab-list,
    .modal-overlay,
    .table-wrap,
    .toolbar,
    #filterSlowThreshold {
        display: none !important;
    }
    /* 打印时用文本显示阈值 */
    .print-threshold-val {
        display: inline !important;
    }

    /* 报表 tab 强制显示 */
    #mainContent { display: block !important; }
    .tab-content { display: none !important; }
    #tab-report { display: block !important; }

    /* 打印时显示标题 */
    .print-header { display: block !important; }

    /* 确保颜色和背景 */
    * { -webkit-print-color-adjust: exact !important; print-color-adjust: exact !important; }
    body { background: #fff !important; }
    .container { max-width: 100% !important; padding: 0 !important; }

    /* KPI 卡片保持网格 */
    .kpi-grid { display: grid !important; grid-template-columns: repeat(5, 1fr) !important; }

    /* 瀑布图颜色 */
    .waterfall-detailed { page-break-inside: avoid; }

    /* 报告区块避免断裂 */
    .report-block { page-break-inside: avoid; }

    a { color: var(--text) !important; text-decoration: none !important; }
}