:root {
  --bg: #eef1f5;
  --card: #ffffff;
  --ink: #1a2433;
  --muted: #6b7787;
  --line: #e2e7ee;
  --accent: #1f5fa6;
  --accent-dark: #16487f;
  --warn: #b9591a;
  --shadow: 0 1px 2px rgba(20, 35, 60, 0.07), 0 4px 14px rgba(20, 35, 60, 0.05);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 15px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.45;
  -webkit-font-smoothing: antialiased;
}

/* ---------- header ---------- */
header {
  background: linear-gradient(135deg, var(--accent-dark), var(--accent));
  color: #fff;
  padding: 18px 20px;
}
.head-wrap { max-width: 1180px; margin: 0 auto; }
header h1 { font-size: 1.32rem; font-weight: 650; letter-spacing: -0.01em; }
header .sub { margin-top: 3px; font-size: 0.82rem; color: #d3e2f1; }

main { max-width: 1180px; margin: 16px auto 32px; padding: 0 20px; }

/* ---------- methodology ---------- */
.method-box {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  box-shadow: var(--shadow);
  margin-bottom: 14px;
}
.method-box summary {
  cursor: pointer;
  padding: 11px 16px;
  font-weight: 600;
  font-size: 0.92rem;
  list-style: none;
  user-select: none;
}
.method-box summary::-webkit-details-marker { display: none; }
.method-box summary::before {
  content: "\25B8";
  display: inline-block;
  margin-right: 8px;
  color: var(--accent);
  transition: transform 0.15s;
}
.method-box[open] summary::before { transform: rotate(90deg); }
.method-body {
  padding: 0 18px 14px;
  font-size: 0.85rem;
  color: #34404f;
}
.method-body p { margin-top: 8px; }
.method-body a { color: var(--accent); }

/* ---------- cards ---------- */
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  box-shadow: var(--shadow);
  padding: 14px 16px;
  margin-bottom: 14px;
}
.card h2 { font-size: 0.98rem; font-weight: 620; margin-bottom: 10px; }
h3 { font-size: 0.86rem; font-weight: 600; }

.muted { color: var(--muted); font-weight: 400; }
.small { font-size: 0.78rem; }
.hint {
  margin-top: 9px;
  font-size: 0.77rem;
  color: var(--muted);
}
.note {
  margin-top: 10px;
  font-size: 0.79rem;
  color: var(--warn);
  background: #fdf2ea;
  border: 1px solid #f4d8c4;
  border-radius: 7px;
  padding: 8px 10px;
}

/* ---------- settings ---------- */
.settings-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}
.field { display: flex; flex-direction: column; gap: 3px; min-width: 130px; }
.field.grow { flex: 1; min-width: 220px; max-width: 300px; }
.field label { font-size: 0.76rem; font-weight: 550; }

input[type="number"] {
  font: inherit;
  font-size: 0.86rem;
  padding: 6px 8px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  color: var(--ink);
  width: 100%;
}
input[type="number"]:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(31, 95, 166, 0.12);
}
.depth-apply { display: flex; gap: 6px; }
.depth-apply input { flex: 1; }

.probe-row { display: flex; gap: 12px; flex-wrap: wrap; }
.probe-array {
  flex: 1;
  min-width: 270px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 9px 11px;
  background: #fafbfc;
}
.probe-array h3 { margin-bottom: 6px; }
.pos-row { display: flex; gap: 8px; }
.pos-row label {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 0.76rem;
  font-weight: 550;
  flex: 1;
}
.pos-row input { width: 100%; }

/* ---------- dropzone ---------- */
.dropzone {
  border: 2px dashed #b9c6d6;
  border-radius: 10px;
  padding: 20px 16px;
  text-align: center;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
  color: var(--muted);
  margin-bottom: 14px;
  background: #fafbfc;
}
.dropzone:hover { background: #f3f7fc; border-color: var(--accent); }
.dropzone.drag { background: #e7f0fa; border-color: var(--accent); color: var(--accent-dark); }
.dropzone svg { color: var(--accent); }
.dropzone p { margin-top: 2px; }
.dropzone strong { color: var(--ink); }

/* ---------- results ---------- */
.results-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 10px;
}
.actions { display: flex; gap: 6px; }

.btn {
  font: inherit;
  font-weight: 550;
  border-radius: 7px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--ink);
  cursor: pointer;
  transition: background 0.12s, border-color 0.12s;
}
.btn.small { font-size: 0.8rem; padding: 6px 11px; }
.btn:hover { background: #eef2f7; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { background: var(--accent-dark); }
.btn.ghost { color: var(--muted); }

.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 8px; }
table { border-collapse: collapse; width: 100%; font-size: 0.8rem; }
thead th {
  background: #eef2f7;
  text-align: right;
  padding: 7px 9px;
  font-weight: 600;
  white-space: nowrap;
  border-bottom: 2px solid var(--line);
  position: sticky;
  top: 0;
}
thead th:first-child { text-align: left; }
tbody td {
  padding: 5px 9px;
  text-align: right;
  border-bottom: 1px solid var(--line);
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}
tbody td:first-child { text-align: left; font-weight: 500; max-width: 230px;
  overflow: hidden; text-overflow: ellipsis; }
tbody tr:last-child td { border-bottom: none; }
tbody tr:hover { background: #f5f8fc; }

td.editable input {
  width: 66px;
  padding: 2px 4px;
  font-size: 0.78rem;
  text-align: right;
  border: 1px solid var(--line);
  border-radius: 4px;
}
td.fallback { color: var(--warn); }
.badge-err { color: var(--warn); font-weight: 600; }

/* Per-array method badge: 3P = three-probe (default), 2P = two-probe fallback */
.meth-3p, .meth-2p {
  display: inline-block;
  margin-left: 4px;
  padding: 1px 5px;
  font-size: 0.65rem;
  font-weight: 600;
  border-radius: 3px;
  vertical-align: middle;
}
.meth-3p { color: #1f5fa6; background: #e6efff; border: 1px solid #c9dcff; }
.meth-2p { color: #b65300; background: #fff1df; border: 1px solid #ffd8a8; }

/* Small info badge ("ⓘ") used next to labels to expose a tooltip without
   adding more text to the visible UI. */
.info-tip {
  display: inline-block;
  margin-left: 4px;
  color: #777;
  font-size: 0.9em;
  cursor: help;
}
.info-tip:hover, .info-tip:focus { color: #1f5fa6; outline: none; }

/* Collapsible inline help block shown under a settings field; clicking the
   "What does this do?" summary expands a short description. */
.field-help {
  margin-top: 6px;
  font-size: 0.78rem;
  color: #555;
}
.field-help > summary {
  cursor: pointer;
  color: #1f5fa6;
  list-style: none;
  display: inline-block;
  padding: 1px 0;
  user-select: none;
}
.field-help > summary::-webkit-details-marker { display: none; }
.field-help > summary::before {
  content: "▸ ";
  display: inline-block;
  width: 0.9em;
  transition: transform 0.15s ease;
  color: #1f5fa6;
}
.field-help[open] > summary::before { content: "▾ "; }
.field-help > summary:hover { text-decoration: underline; }
.field-help > ul {
  margin: 6px 0 4px 0;
  padding-left: 1.2em;
}
.field-help > ul li { margin-bottom: 3px; }
.field-help > p { margin: 4px 0 0 0; }

/* Per-record layout tag shown next to the file name when the CSV is
   2-channel ("2-probe") or 3-channel ("3-probe"); the dual-array case
   ("6-channel, two 3-probe arrays") shows no tag. */
.lay-tag {
  display: inline-block;
  margin-left: 4px;
  padding: 1px 5px;
  font-size: 0.65rem;
  font-weight: 600;
  color: #444;
  background: #f0f0f0;
  border: 1px solid #d0d0d0;
  border-radius: 3px;
  vertical-align: middle;
}

.row-del {
  border: none;
  background: none;
  color: var(--muted);
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  padding: 1px 6px;
  border-radius: 4px;
}
.row-del:hover { background: #fde8e0; color: var(--warn); }

/* ---------- footer ---------- */
.footer-wave { line-height: 0; margin-top: 20px; }
.footer-wave svg { display: block; width: 100%; height: 46px; }
.footer-wave path { fill: var(--accent-dark); }
.site-footer {
  background: linear-gradient(135deg, var(--accent-dark), var(--accent));
  color: #d3e2f1;
  padding: 6px 20px 30px;
}
.footer-inner { max-width: 1180px; margin: 0 auto; text-align: center; }
.footer-brand {
  color: #fff;
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  margin-bottom: 6px;
}
.footer-tag {
  max-width: 600px;
  margin: 0 auto;
  font-size: 0.84rem;
  color: #c8dcef;
  line-height: 1.5;
}
.footer-links {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  margin: 18px 0 14px;
}
.footer-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: #fff;
  color: var(--accent-dark);
  font-weight: 600;
  font-size: 0.86rem;
  padding: 8px 16px;
  border-radius: 8px;
  text-decoration: none;
  transition: transform 0.12s, box-shadow 0.12s;
}
.footer-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.25);
}
.footer-btn svg { width: 17px; height: 17px; fill: currentColor; }
.doi-badge {
  display: inline-flex;
  border-radius: 6px;
  overflow: hidden;
  font-size: 0.82rem;
  font-weight: 600;
  text-decoration: none;
  box-shadow: 0 3px 12px rgba(0, 0, 0, 0.22);
  transition: transform 0.12s;
}
.doi-badge:hover { transform: translateY(-2px); }
.doi-label { background: #555; color: #fff; padding: 7px 10px; }
.doi-value { background: #2596d4; color: #fff; padding: 7px 12px; }
.footer-cite {
  font-size: 0.77rem;
  color: #b6cee5;
  margin-top: 2px;
}
.footer-fine {
  font-size: 0.74rem;
  color: #9bb6d2;
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
}

/* Wave-type toggle styles removed in v0.3.0 along with the toggle itself. */

/* ---------- visualization ---------- */
.viz-box {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  box-shadow: var(--shadow);
  margin-bottom: 14px;
}
.viz-box > summary {
  cursor: pointer;
  padding: 11px 16px;
  font-weight: 600;
  font-size: 0.92rem;
  list-style: none;
  user-select: none;
}
.viz-box > summary::-webkit-details-marker { display: none; }
.viz-box > summary::before {
  content: "\25B8";
  display: inline-block;
  margin-right: 8px;
  color: var(--accent);
  transition: transform 0.15s;
}
.viz-box[open] > summary::before { transform: rotate(90deg); }
.viz-body { padding: 0 16px 14px; }
.viz-controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 10px;
}
.viz-file { display: flex; align-items: center; gap: 8px; }
.viz-file label { font-size: 0.82rem; font-weight: 550; }
.viz-file select {
  font: inherit;
  font-size: 0.84rem;
  padding: 5px 8px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  max-width: 360px;
}
.viz-ctl { display: inline-flex; align-items: center; gap: 6px; }
.viz-smooth {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 10px;
  font-size: 0.8rem;
  font-weight: 550;
  color: var(--ink);
}
.viz-smooth input[type="range"] {
  flex: 1;
  max-width: 340px;
  accent-color: var(--accent);
  cursor: pointer;
}
.viz-smooth-val {
  min-width: 64px;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}
.viz-tip {
  position: absolute;
  display: none;
  pointer-events: none;
  background: rgba(26, 36, 51, 0.92);
  color: #fff;
  font-size: 0.74rem;
  padding: 3px 8px;
  border-radius: 5px;
  white-space: nowrap;
  z-index: 5;
}
.viz-tip b { font-weight: 650; }
.viz-probes {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  font-size: 0.82rem;
  font-weight: 550;
}
.viz-probes label { display: flex; align-items: center; gap: 4px; cursor: pointer; }
.viz-probes input { margin: 0; cursor: pointer; }
.viz-all { border-left: 1px solid var(--line); padding-left: 10px; }
.viz-plot { position: relative; }
#vizCanvas {
  width: 100%;
  height: 380px;
  display: block;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}
#vizOverlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 380px;
  border: 1px solid transparent;
  pointer-events: none;
}
.viz-zoom {
  position: absolute;
  top: 8px;
  right: 8px;
  display: flex;
  gap: 4px;
}
.viz-zoom button {
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.92);
  color: var(--accent-dark);
  cursor: pointer;
  padding: 0;
  transition: background 0.12s, border-color 0.12s;
}
.viz-zoom button:hover {
  background: #eef2f7;
  border-color: var(--accent);
}
.viz-zoom button:active { background: #e0e8f1; }
.viz-zoom button.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
#vizCanvas.mode-box { cursor: crosshair; }
#vizCanvas.mode-pan { cursor: grab; }
#vizCanvas.mode-pan:active { cursor: grabbing; }

@media (max-width: 560px) {
  main { padding: 0 12px; }
  .field { min-width: 110px; }
  .mode-note { margin-left: 0; width: 100%; }
  .viz-file select { max-width: 200px; }
}