:root {
  --bg: #0b0d10;
  --panel: #11151a;
  --card: #151a21;
  --text: #e6eef8;
  --muted: #9db0c5;
  --brand: #4da3ff;
  --accent: #7bd88f;
  --warn: #ffcc66;
  --danger: #ff6b6b;
  --border: #253241;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  color: var(--text);
  background: var(--bg);
  font: 14px/1.5 -apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,"Noto Sans",sans-serif,"Apple Color Emoji","Segoe UI Emoji";
}

.app-header, .app-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
}
.app-footer {
  border-top: 1px solid var(--border);
  border-bottom: none;
  gap: 12px;
}

.app-header h1 { margin: 0; font-size: 18px; }
.actions { display: flex; gap: 6px; flex-wrap: wrap; }
.actions button { font-size: 12px; padding: 6px 10px; }
button {
    background: #ff0000;
    color: #ffffff;
    border: none;
    padding: 8px 12px;
    border-radius: 8px;
    cursor: pointer;
    transition: transform .04s 
ease, filter .15s 
ease, background .2s 
ease;
}
button:hover { filter: brightness(1.05); }
button:disabled { opacity: 0.6; cursor: not-allowed; }
button:active { transform: translateY(1px); }

.app-main { padding: 16px; display: grid; gap: 16px; }
.layout { display: grid; grid-template-columns: 220px 1fr; }
.sidebar { background: var(--panel); border-right: 1px solid var(--border); min-height: calc(100vh - 84px); }
.tabs { display: grid; padding: 12px; gap: 8px; }
.tab { background: transparent; color: var(--text); border: 1px solid var(--border); padding: 10px 12px; border-radius: 10px; text-align: left; cursor: pointer; }
.tab.active, .tab:hover { background: #0f1318; border-color: #2a3a4d; }
.panel[data-tab] { display: none; }
.panel[data-tab].active { display: block; }
.panel { background: var(--panel); border: 1px solid var(--border); border-radius: 12px; padding: 16px; }
.panel h2 { margin: 0 0 12px; font-size: 16px; }
.card { background: var(--card); border: 1px solid var(--border); border-radius: 10px; padding: 12px; }

.field { display: grid; gap: 6px; margin-bottom: 12px; }
label { color: var(--muted); font-size: 12px; }
input[type="text"], input[type="number"], select, textarea {
  width: 100%;
  background: #0f1318;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 10px;
  outline: none;
}
input:focus, select:focus, textarea:focus { border-color: #355173; box-shadow: 0 0 0 2px rgba(77,163,255,0.15); }
textarea { min-height: 120px; resize: vertical; }

.row { display: grid; grid-template-columns: 1fr auto; gap: 12px; align-items: end; }
.row .col.right { justify-self: end; }
.grid-2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; }

@media (max-width: 1024px) { .grid-3 { grid-template-columns: 1fr; } }
@media (max-width: 900px) { .grid-2 { grid-template-columns: 1fr; } }
@media (max-width: 900px) { .layout { grid-template-columns: 1fr; } .sidebar { min-height: auto; } .tabs { grid-auto-flow: column; overflow: auto; } }

.toolbar { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 12px; align-items: end; }
@media (max-width: 1400px) { .toolbar { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (max-width: 900px) { .toolbar { grid-template-columns: 1fr 1fr; } }
.toolbar .compact label { font-size: 11px; }
.toolbar .compact { display: grid; align-content: end; }
.toolbar .compact.checkbox { align-content: center; }
.toolbar .compact.checkbox label { display: inline-flex; align-items: center; gap: 8px; font-size: 12px; }

.stats { margin: 12px 0; color: var(--muted); display: flex; flex-wrap: wrap; gap: 10px; }

.progress { position: relative; height: 10px; background: #10161d; border: 1px solid var(--border); border-radius: 999px; overflow: hidden; margin: 8px 0 12px; }
.progress.hidden { display: none; }
.progress .bar { position: absolute; left: 0; top: 0; bottom: 0; background: linear-gradient(90deg, var(--brand), #7cc8ff); width: 0%; }
.progress .label { position: absolute; top: -22px; right: 0; font-size: 12px; color: var(--muted); }

.table-wrap { overflow: auto; border: 1px solid var(--border); border-radius: 10px; }
table { width: 100%; border-collapse: separate; border-spacing: 0; font-size: 13px; }
thead th { position: sticky; top: 0; background: #0e1217; border-bottom: 1px solid var(--border); text-align: left; padding: 8px; }
tbody td { border-top: 1px solid var(--border); padding: 10px 8px; }
tbody tr:hover { background: #0f1318; }

/* rounded rows */
tbody tr:first-child td:first-child { border-top-left-radius: 8px; }
tbody tr:first-child td:last-child { border-top-right-radius: 8px; }
tbody tr:last-child td:first-child { border-bottom-left-radius: 8px; }
tbody tr:last-child td:last-child { border-bottom-right-radius: 8px; }

.tag { display: inline-block; padding: 2px 6px; border-radius: 999px; background: #1a2230; border: 1px solid var(--border); margin-right: 4px; }
.tag.hot { background: rgba(77,163,255,0.15); border-color: #2a6fb6; }
.tag.cold { background: rgba(255,107,107,0.15); border-color: #b23b3b; }
.tag.neutral { background: rgba(255,204,102,0.15); border-color: #b3872b; }
.tag.primary { background: rgba(123,216,143,0.15); border-color: #4aa563; }

.muted { color: var(--muted); }
.empty { text-align: center; color: var(--muted); padding: 24px 12px; }

.load-more-wrap { display: flex; align-items: center; gap: 10px; justify-content: center; padding-top: 10px; }
.load-more-wrap button { background: #1b2634; color: var(--text); }

/* Analytics & Tools */
.analytics-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; margin-bottom: 20px; }
.tools-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
@media (max-width: 1200px) { .analytics-grid, .tools-grid { grid-template-columns: 1fr; } }

.chart-container { height: 200px; position: relative; }
.tag-cloud { min-height: 200px; display: flex; flex-wrap: wrap; gap: 8px; align-items: center; justify-content: center; }
.tag-cloud .tag { font-size: 12px; padding: 4px 8px; margin: 2px; }
.tag-cloud .tag.large { font-size: 16px; }
.tag-cloud .tag.medium { font-size: 14px; }
.tag-cloud .tag.small { font-size: 10px; }

.density-analysis { min-height: 200px; }
.insights-section { margin-top: 20px; }
.insights-container { background: var(--card); border: 1px solid var(--border); border-radius: 8px; padding: 16px; }
.insight-item { margin-bottom: 12px; padding: 8px; background: rgba(77,163,255,0.1); border-left: 3px solid var(--brand); border-radius: 4px; }

.results-container { margin-top: 12px; max-height: 300px; overflow-y: auto; border: 1px solid var(--border); border-radius: 8px; padding: 12px; background: var(--card); }
.cluster-group { margin-bottom: 16px; }
.cluster-title { font-weight: bold; color: var(--brand); margin-bottom: 8px; }
.cluster-items { display: flex; flex-wrap: wrap; gap: 4px; }
.cluster-item { background: rgba(77,163,255,0.15); padding: 2px 6px; border-radius: 4px; font-size: 12px; }

.similarity-pair { display: flex; justify-content: space-between; align-items: center; padding: 8px; border-bottom: 1px solid var(--border); }
.similarity-pair:last-child { border-bottom: none; }
.similarity-score { color: var(--accent); font-weight: bold; }

.expand-item { padding: 6px 8px; margin: 2px; background: rgba(123,216,143,0.15); border-radius: 4px; display: inline-block; font-size: 12px; }

.competition-item { display: flex; justify-content: space-between; align-items: center; padding: 8px; border-bottom: 1px solid var(--border); }
.competition-item:last-child { border-bottom: none; }
.competition-score { font-weight: bold; }
.competition-score.high { color: var(--danger); }
.competition-score.medium { color: var(--warn); }
.competition-score.low { color: var(--accent); }

.density-item { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; }
.density-item .word { min-width: 80px; font-weight: 500; }
.density-item .count { min-width: 30px; text-align: right; color: var(--muted); }
.density-item .bar { height: 4px; background: var(--brand); border-radius: 2px; }

.template-buttons { display: flex; flex-wrap: wrap; gap: 8px; }
.template-btn { background: #1b2634; color: var(--text); border: 1px solid var(--border); padding: 6px 12px; border-radius: 6px; font-size: 12px; }
.template-btn:hover { background: #2a3a4d; border-color: var(--brand); }

.advanced-filters { margin-top: 16px; }
.filter-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; margin-top: 12px; }
@media (max-width: 800px) { .filter-grid { grid-template-columns: 1fr; } }
.range-inputs { display: flex; align-items: center; gap: 8px; }
.range-inputs input { flex: 1; }
.range-inputs span { color: var(--muted); }

/* Trend Analysis */
.trend-item { margin-bottom: 16px; padding: 12px; background: var(--card); border-radius: 8px; border: 1px solid var(--border); }
.trend-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 8px; }
.trend-indicator { font-weight: bold; }
.trend-indicator.rising { color: var(--accent); }
.trend-indicator.declining { color: var(--danger); }
.trend-indicator.slight_rise { color: var(--warn); }
.trend-indicator.slight_decline { color: var(--warn); }
.trend-indicator.stable { color: var(--muted); }
.trend-stats { display: flex; gap: 12px; margin-bottom: 8px; font-size: 12px; color: var(--muted); }
.trend-chart { display: flex; align-items: end; gap: 2px; height: 40px; }
.trend-bar { width: 8px; background: var(--brand); border-radius: 2px; transition: all 0.3s ease; }
.trend-bar:hover { background: var(--accent); }

/* SERP Analysis */
.serp-item { margin-bottom: 16px; padding: 12px; background: var(--card); border-radius: 8px; border: 1px solid var(--border); }
.serp-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 8px; }
.difficulty { font-weight: bold; }
.difficulty.easy { color: var(--accent); }
.difficulty.medium { color: var(--warn); }
.difficulty.hard { color: var(--danger); }
.serp-stats { display: flex; gap: 12px; margin-bottom: 8px; font-size: 12px; color: var(--muted); }
.serp-features { font-size: 12px; color: var(--muted); }

/* Performance Tracking */
.track-item { margin-bottom: 16px; padding: 12px; background: var(--card); border-radius: 8px; border: 1px solid var(--border); }
.track-header { margin-bottom: 12px; }
.track-metrics { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: 12px; }
.metric { display: flex; flex-direction: column; align-items: center; padding: 8px; background: rgba(77,163,255,0.05); border-radius: 6px; }
.metric-label { font-size: 11px; color: var(--muted); margin-bottom: 4px; }
.metric-value { font-weight: bold; font-size: 14px; }
.metric-value.up { color: var(--accent); }
.metric-value.down { color: var(--danger); }
.metric-value.stable { color: var(--muted); }

.checkbox-group { display: flex; flex-wrap: wrap; gap: 12px; }
.checkbox-group label { display: flex; align-items: center; gap: 4px; font-size: 12px; }

/* Feedback Modal */
.modal { position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.7); z-index: 1000; display: flex; align-items: center; justify-content: center; }
.modal.hidden { display: none; }
.modal-content { background: var(--bg); border-radius: 12px; max-width: 600px; width: 90%; max-height: 80vh; overflow-y: auto; box-shadow: 0 20px 40px rgba(0,0,0,0.3); }
.modal-header { display: flex; justify-content: space-between; align-items: center; padding: 20px; border-bottom: 1px solid var(--border); }
.modal-header h3 { margin: 0; color: var(--text); }
.close-btn { background: none; border: none; font-size: 24px; color: var(--muted); cursor: pointer; padding: 0; width: 30px; height: 30px; display: flex; align-items: center; justify-content: center; }
.close-btn:hover { color: var(--text); }
.modal-body { padding: 20px; }
.feedback-section { margin-bottom: 24px; }
.feedback-section h4 { margin: 0 0 12px 0; color: var(--text); font-size: 16px; }
.wechat-info { display: flex; gap: 20px; align-items: center; }
.wechat-qr { flex-shrink: 0; }
.qr-placeholder {
    width: 150px;
    height: 200px;
    ckground: var(--card);
    border: 2px dashed var(--border);
    border-radius: 8px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--muted);
    padding: 20px;
}
.qr-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    margin-bottom: 10px;
}
.qr-placeholder span { font-size: 32px; margin-bottom: 8px; }
.qr-placeholder p { margin: 0; font-size: 12px; }
.wechat-details { flex: 1; }
.wechat-details p { margin: 8px 0; color: var(--text); }
.copy-btn { background: var(--brand); color: #051422; border: none; padding: 6px 12px; border-radius: 6px; font-size: 12px; cursor: pointer; margin-top: 8px; }
.copy-btn:hover { background: var(--accent); }
.feedback-form .field { margin-bottom: 16px; }
.feedback-form label { display: block; margin-bottom: 6px; color: var(--text); font-weight: 500; }
.feedback-form select, .feedback-form input, .feedback-form textarea { width: 100%; padding: 8px 12px; background: var(--card); border: 1px solid var(--border); border-radius: 6px; color: var(--text); font-size: 14px; }
.feedback-form select:focus, .feedback-form input:focus, .feedback-form textarea:focus { border-color: var(--brand); outline: none; }
.submit-btn { background: var(--brand); color: #051422; border: none; padding: 10px 20px; border-radius: 6px; font-size: 14px; font-weight: 500; cursor: pointer; width: 100%; }
.submit-btn:hover { background: var(--accent); }
.feature-vote { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 8px; }
.vote-item { padding: 8px; background: var(--card); border-radius: 6px; border: 1px solid var(--border); }
.vote-item label { display: flex; align-items: center; gap: 8px; margin: 0; cursor: pointer; color: var(--text); }
.vote-item input[type="checkbox"] { margin: 0; }
@media (max-width: 600px) { .wechat-info { flex-direction: column; text-align: center; } .feature-vote { grid-template-columns: 1fr; } }