:root {
  --bg: #f6f8fa;
  --bg-elev: #ffffff;
  --bg-row: #f8fafc;
  --bg-hover: #f1f5f9;
  --bg-head: #f1f5f9;
  --border: #e2e8f0;
  --text: #0f172a;
  --muted: #64748b;
  --accent: #0d9488;
  --accent-dim: #14b8a6;
  --cheap: #059669;
  --mid: #d97706;
  --pricey: #dc2626;
  --bar-track: #e9eef4;
  --shadow: 0 4px 18px rgba(15, 23, 42, 0.08);
  --radius: 12px;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", "Cascadia Code", Menlo, monospace;
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--sans);
  background:
    radial-gradient(1200px 600px at 80% -10%, rgba(13, 148, 136, 0.06), transparent 60%),
    var(--bg);
  color: var(--text);
  font-size: 14px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.muted { color: var(--muted); }

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 24px;
  padding: 28px 32px 18px;
  flex-wrap: wrap;
}
.brand { display: flex; gap: 16px; align-items: center; }
.logo {
  font-size: 28px;
  color: var(--accent);
}
.topbar h1 {
  margin: 0;
  font-size: 22px;
  letter-spacing: -0.02em;
  font-weight: 700;
}
.tagline { margin: 2px 0 0; color: var(--muted); font-size: 13px; max-width: 52ch; }
.meta { text-align: right; font-size: 12px; color: var(--muted); font-family: var(--mono); }
.meta strong { color: var(--text); }

/* summary cards */
.summary {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 14px;
  padding: 6px 32px 20px;
}
.card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 18px;
}
.card .k { font-size: 11px; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); }
.card .v { font-size: 26px; font-weight: 700; margin-top: 6px; font-family: var(--mono); letter-spacing: -0.02em; }
.card .v small { font-size: 13px; color: var(--muted); font-weight: 500; }
.card .sub { font-size: 12px; color: var(--muted); margin-top: 4px; }
.card .v.accent { color: var(--accent); }
.card .v.pricey { color: var(--pricey); }

/* controls */
.controls {
  display: flex;
  gap: 14px;
  align-items: center;
  padding: 0 32px 16px;
  flex-wrap: wrap;
}
#search {
  flex: 1 1 260px;
  min-width: 200px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: 9px;
  padding: 9px 13px;
  color: var(--text);
  font-size: 13px;
  font-family: var(--sans);
}
#search:focus { outline: none; border-color: var(--accent-dim); }
.seg { display: inline-flex; background: var(--bg-elev); border: 1px solid var(--border); border-radius: 9px; padding: 3px; }
.seg-btn {
  border: 0; background: transparent; color: var(--muted);
  padding: 6px 14px; border-radius: 7px; cursor: pointer; font-size: 13px; font-family: var(--sans);
}
.seg-btn.active { background: var(--accent-dim); color: #04201b; font-weight: 600; }
.checkbox { display: inline-flex; align-items: center; gap: 7px; color: var(--muted); font-size: 13px; cursor: pointer; }
.checkbox input { accent-color: var(--accent-dim); }
.slider-ctrl {
  display: inline-flex; flex-direction: column; gap: 4px;
  background: var(--bg-elev); border: 1px solid var(--border); border-radius: 9px;
  padding: 6px 12px 8px; min-width: 180px;
}
.slider-ctrl label { font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.05em; }
.slider-ctrl label strong { color: var(--accent); font-family: var(--mono); }
.slider-ctrl input[type="range"] { width: 100%; accent-color: var(--accent-dim); cursor: pointer; }

/* scatter chart */
main { padding: 0 32px 40px; }
.chart-card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px 20px 14px;
}
.chart-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 20px; flex-wrap: wrap; }
.chart-head h2 { margin: 0; font-size: 16px; font-weight: 700; letter-spacing: -0.01em; }
.chart-head .muted { margin: 3px 0 0; font-size: 12px; }
.chart-stat { text-align: right; font-family: var(--mono); font-size: 12px; color: var(--muted); }
.chart-stat b { color: var(--accent); font-size: 18px; }
.chart-body { position: relative; margin-top: 10px; }
#chart svg { width: 100%; height: auto; display: block; }
.chart-legend { font-size: 11px; margin: 8px 0 0; }
.ax-line { stroke: var(--border); stroke-width: 1; }
.ax-grid { stroke: var(--border); stroke-width: 1; stroke-dasharray: 2 4; opacity: 0.5; }
.ax-label { fill: var(--muted); font-size: 11px; font-family: var(--mono); }
.ax-title { fill: var(--muted); font-size: 12px; font-family: var(--sans); }
.trend { stroke: var(--accent); stroke-width: 1.6; stroke-dasharray: 6 5; opacity: 0.85; }
.dot-pt { fill: var(--accent-dim); fill-opacity: 0.55; stroke: var(--accent); stroke-width: 1; cursor: pointer; transition: fill-opacity 0.1s; }
.dot-pt:hover { fill-opacity: 0.95; stroke-width: 2; }
.chart-tip {
  position: absolute; z-index: 5;
  background: var(--bg-elev); border: 1px solid var(--border); border-radius: 8px;
  padding: 8px 11px; font-size: 12px; box-shadow: var(--shadow); max-width: 240px;
}
.chart-tip .t-name { font-weight: 700; margin-bottom: 4px; }
.chart-tip .t-row { display: flex; justify-content: space-between; gap: 16px; color: var(--muted); font-family: var(--mono); }
.chart-tip .t-row b { color: var(--text); }
.chart-tip .t-jump {
  margin-top: 8px; width: 100%; border: 0; border-radius: 6px; cursor: pointer;
  background: var(--accent-dim); color: #04201b; font-weight: 600; font-size: 12px;
  padding: 7px 10px; font-family: var(--sans);
}

/* table */
.table-wrap {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg-elev);
  box-shadow: var(--shadow);
}
table { width: 100%; border-collapse: collapse; }
thead th {
  position: sticky; top: 0;
  background: var(--bg-head);
  text-align: left;
  font-size: 11px; text-transform: uppercase; letter-spacing: 0.05em;
  color: var(--muted); font-weight: 600;
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  cursor: pointer; user-select: none; white-space: nowrap;
}
thead th.num { text-align: right; }
thead th.range-col { cursor: default; width: 230px; }
thead th[data-sort]:hover { color: var(--text); }
thead th.sorted-asc::after { content: " ▲"; color: var(--accent); }
thead th.sorted-desc::after { content: " ▼"; color: var(--accent); }

tbody tr.model-row { border-bottom: 1px solid var(--border); cursor: pointer; transition: background 0.12s; }
tbody tr.model-row:hover { background: var(--bg-hover); }
tbody tr.model-row.open { background: var(--bg-hover); }
td { padding: 11px 14px; vertical-align: middle; }
td.num { text-align: right; font-family: var(--mono); font-variant-numeric: tabular-nums; }

.model-cell { display: flex; align-items: center; gap: 10px; }
.model-cell .chev { color: var(--muted); font-size: 10px; transition: transform 0.15s; }
tr.open .chev { transform: rotate(90deg); color: var(--accent); }
.model-name { font-weight: 600; }
.model-sub { font-size: 11px; color: var(--muted); display: block; margin-top: 1px; }
.tag {
  display: inline-block; font-size: 10px; padding: 1px 6px; border-radius: 5px;
  background: var(--bar-track); color: var(--muted); margin-left: 6px; vertical-align: middle;
}

.price { font-family: var(--mono); font-variant-numeric: tabular-nums; }
.price .prov { display: block; font-size: 10px; color: var(--muted); }
.cheap { color: var(--cheap); }
.pricey { color: var(--pricey); }

.spread-badge {
  font-family: var(--mono); font-weight: 700; padding: 2px 8px; border-radius: 6px;
  font-size: 13px;
}
.spread-lo { color: var(--cheap); }
.spread-mid { color: var(--mid); }
.spread-hi { color: var(--pricey); background: rgba(248, 113, 113, 0.12); }

/* range bar */
.range-bar { position: relative; height: 8px; background: var(--bar-track); border-radius: 5px; }
.range-fill {
  position: absolute; top: 0; bottom: 0;
  background: linear-gradient(90deg, var(--cheap), var(--mid) 55%, var(--pricey));
  border-radius: 5px;
}
.range-labels { display: flex; justify-content: space-between; font-size: 10px; color: var(--muted); margin-top: 3px; font-family: var(--mono); }

/* expanded provider detail */
tr.detail-row > td { padding: 0; background: var(--bg-row); }
.detail { padding: 6px 14px 16px 40px; }
.prov-table { width: 100%; border-collapse: collapse; font-size: 12px; }
.prov-table th { text-align: right; color: var(--muted); font-weight: 500; padding: 6px 10px; border-bottom: 1px solid var(--border); font-size: 11px; }
.prov-table th:first-child { text-align: left; }
.prov-table td { padding: 6px 10px; font-family: var(--mono); text-align: right; }
.prov-table td:first-child { text-align: left; font-family: var(--sans); }
.prov-table tr:hover { background: var(--bg-hover); }
.prov-bar-cell { width: 30%; }
.prov-bar { height: 6px; border-radius: 4px; background: var(--accent-dim); opacity: 0.8; }
.dot { display: inline-block; width: 7px; height: 7px; border-radius: 50%; margin-right: 7px; }
.aa-row { margin-top: 12px; font-size: 12px; color: var(--muted); display: flex; gap: 20px; flex-wrap: wrap; }
.aa-row b { color: var(--text); font-family: var(--mono); }

.footnote { padding: 8px 32px 48px; max-width: 980px; font-size: 12px; color: var(--muted); }
.footnote p { margin: 6px 0; }
abbr { text-decoration: underline dotted; cursor: help; }

.empty { text-align: center; padding: 40px; color: var(--muted); }

/* tablet: drop the range-bar column, tighten padding */
@media (max-width: 860px) {
  .topbar, .summary, .controls, main, .footnote { padding-left: 16px; padding-right: 16px; }
  thead th.range-col, td.range-col-cell { display: none; }
  .meta { text-align: left; }
  .summary { grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); }
}

/* phone: card layout + compact chrome */
@media (max-width: 640px) {
  .topbar { padding: 16px 14px 10px; align-items: center; }
  .topbar h1 { font-size: 19px; }
  .tagline { display: none; }
  .logo { font-size: 22px; }
  .summary { grid-template-columns: 1fr 1fr; gap: 10px; padding: 4px 14px 14px; }
  .card { padding: 12px 13px; }
  .card .v { font-size: 20px; }
  .card .k, .card .sub { font-size: 10.5px; }

  /* controls: full-width search; toggles become horizontal scroll rows */
  .controls { gap: 10px; padding-bottom: 12px; }
  #search { flex: 1 1 100%; padding: 11px 13px; }
  .seg { max-width: 100%; overflow-x: auto; -webkit-overflow-scrolling: touch; scrollbar-width: none; }
  .seg::-webkit-scrollbar { display: none; }
  .seg-btn { white-space: nowrap; padding: 9px 15px; }   /* larger tap targets */
  .slider-ctrl { flex: 1 1 100%; }
  .checkbox { flex: 1 1 100%; padding: 4px 0; }

  /* model table -> stacked cards */
  .table-wrap { border: 0; background: transparent; box-shadow: none; overflow: visible; }
  #models-table, #models-table tbody { display: block; }
  #models-table > thead { display: none; }   /* hide only the main table header, not the drill-down's */
  tr.model-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px 14px;
    align-items: end;
    background: var(--bg-elev);
    border: 1px solid var(--border);
    border-radius: 12px;
    box-shadow: var(--shadow);
    padding: 13px 15px;
    margin-bottom: 10px;
  }
  tr.model-row.open { border-color: var(--accent-dim); }
  tr.model-row td { display: flex; flex-direction: column; gap: 2px; padding: 0; border: 0; text-align: left; }
  td.num { text-align: left; }
  tr.model-row td::before {
    content: attr(data-label);
    font-size: 10px; text-transform: uppercase; letter-spacing: 0.05em; color: var(--muted);
  }
  tr.model-row td[data-col="rank"] { display: none; }
  tr.model-row td[data-col="range"] { display: none; } /* redundant with cheapest/priciest */
  td[data-col="model"] { grid-column: 1 / -1; }
  td[data-col="model"]::before { display: none; }
  td[data-col="model"] .model-name { font-size: 15px; }
  td[data-col="spread"] { grid-column: 1 / -1; flex-direction: row; align-items: center; gap: 8px; }
  td[data-col="spread"]::before { order: 0; }
  td[data-col="spread"] .spread-badge { font-size: 15px; }
  .price .prov { font-size: 10px; }

  /* provider drill-down: let the wide table scroll sideways inside the card */
  tr.detail-row { display: block; margin: -6px 0 12px; }
  tr.detail-row > td { display: block; padding: 0; }
  .detail { padding: 4px 12px 14px; overflow-x: auto; -webkit-overflow-scrolling: touch; }
  .prov-table { min-width: 560px; }

  .footnote { padding: 8px 14px 40px; }
}