:root {
  --bg: #f4f6fa;
  --card: #ffffff;
  --text: #1a2233;
  --muted: #64748b;
  --border: #e2e8f0;
  --accent: #2563eb;
  --accent-soft: #dbeafe;
  --green: #16a34a;
  --green-soft: #dcfce7;
  --amber: #d97706;
  --amber-soft: #fef3c7;
  --red: #dc2626;
  --radius: 12px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

header {
  max-width: 980px;
  margin: 0 auto;
  padding: 32px 20px 8px;
}
header h1 { margin: 0 0 4px; font-size: 26px; }
header .sub { margin: 0; color: var(--muted); font-size: 14px; }

main {
  max-width: 980px;
  margin: 0 auto;
  padding: 16px 20px 60px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.06);
}
.card h2 { margin: 0 0 12px; font-size: 18px; }

/* Upload */
.drop-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 28px;
  text-align: center;
  transition: border-color 0.15s, background 0.15s;
}
.drop-zone.dragover { border-color: var(--accent); background: var(--accent-soft); }
.drop-zone p { margin: 6px 0; }
.drop-icon { font-size: 34px; }
.file-name { color: var(--accent); font-weight: 600; font-size: 14px; }

.options {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  margin-top: 16px;
}
.opt { display: flex; flex-direction: column; gap: 4px; font-size: 14px; min-width: 260px; }
.opt.checkbox { flex-direction: row; align-items: center; gap: 8px; }
.opt input[type="range"] { width: 260px; }
.hint { color: var(--muted); font-size: 12px; }

.error { color: var(--red); font-weight: 600; }

/* Tab & column config */
.config-grid { display: flex; flex-wrap: wrap; gap: 16px; }
.cfg {
  flex: 1 1 300px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.cfg-title {
  align-self: flex-start;
  border-radius: 999px;
  padding: 1px 10px;
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.cfg-title.l1 { background: var(--accent-soft); color: var(--accent); }
.cfg-title.l2 { background: #fce7f3; color: #db2777; }
.cfg label { display: flex; align-items: center; gap: 10px; font-size: 14px; font-weight: 600; }
.cfg select {
  flex: 1;
  font: inherit;
  font-weight: 400;
  padding: 6px 8px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
  min-width: 0;
}

/* Buttons */
.btn {
  display: inline-block;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  border-radius: 8px;
  padding: 8px 16px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
}
.btn:hover { background: #f1f5f9; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { background: #1d4ed8; }
.btn.small { padding: 5px 12px; font-size: 13px; }
.btn.merge { background: var(--green); border-color: var(--green); color: #fff; }
.btn.merge:hover { background: #15803d; }
.btn.keep:hover { border-color: var(--muted); }

/* Stats */
.stats { display: flex; flex-wrap: wrap; gap: 12px; }
.stat {
  flex: 1 1 140px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px 16px;
}
.stat .num { font-size: 24px; font-weight: 700; }
.stat .lbl { font-size: 12px; color: var(--muted); }

/* Review */
.review-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 12px;
}
.review-header h2 { margin: 0; }
.bulk { display: flex; gap: 8px; }

.pill {
  display: inline-block;
  background: var(--amber-soft);
  color: var(--amber);
  border-radius: 999px;
  padding: 1px 10px;
  font-size: 13px;
  vertical-align: middle;
}

/* Filter bars */
.filters {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  padding: 10px 12px;
  background: #f8fafc;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 13px;
}
.filters input[type="search"] {
  flex: 1 1 160px;
  min-width: 140px;
  font: inherit;
  padding: 6px 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
}
.filters select {
  font: inherit;
  padding: 6px 8px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
}
.filters .range-lbl { display: flex; align-items: center; gap: 5px; font-weight: 600; }
.filters input[type="number"] {
  width: 58px;
  font: inherit;
  padding: 6px 8px;
  border: 1px solid var(--border);
  border-radius: 8px;
}
.filters .hint { margin-left: auto; }

.no-match {
  color: var(--muted);
  font-size: 14px;
  padding: 16px;
  text-align: center;
}

.pair {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-bottom: 10px;
}
.pair.decided-merge { border-color: var(--green); background: var(--green-soft); }
.pair.decided-keep { border-color: var(--border); background: #f8fafc; opacity: 0.85; }

.pair-top {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.pair-names { flex: 1 1 340px; display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.name-box { display: flex; flex-direction: column; gap: 2px; }
.name-box .who { font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.04em; }
.name-box label { display: flex; align-items: center; gap: 6px; font-weight: 600; cursor: pointer; }
.vs { color: var(--muted); font-size: 13px; }

.score {
  font-weight: 700;
  font-size: 14px;
  border-radius: 8px;
  padding: 4px 10px;
  background: var(--amber-soft);
  color: var(--amber);
  white-space: nowrap;
}
.score.high { background: var(--green-soft); color: var(--green); }

.pair-actions { display: flex; gap: 8px; }
.decision-note { font-size: 13px; font-weight: 600; }
.decision-note.merge { color: var(--green); }
.decision-note.keep { color: var(--muted); }

.pair-detail {
  margin-top: 10px;
  font-size: 12px;
  color: var(--muted);
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}
.pair-detail div b { color: var(--text); }

/* Table */
.table-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: 8px; }
table { border-collapse: collapse; width: 100%; font-size: 13px; }
th, td { padding: 7px 12px; border-bottom: 1px solid var(--border); text-align: left; white-space: nowrap; }
th { background: #f8fafc; position: sticky; top: 0; font-size: 12px; text-transform: uppercase; letter-spacing: 0.03em; color: var(--muted); }
tr:last-child td { border-bottom: none; }

.src { border-radius: 999px; padding: 1px 10px; font-size: 12px; font-weight: 600; }
.src.merge { background: var(--green-soft); color: var(--green); }
.src.l1 { background: var(--accent-soft); color: var(--accent); }
.src.l2 { background: #fce7f3; color: #db2777; }