:root {
  color-scheme: light;
  --accent: #2a5bff;
  --accent-hover: #1e4acc;
  --fg: #1a1a1a;
  --fg-muted: #5a5a5a;
  --fg-faint: #8a8a8a;
  --bg: #f7f7f5;
  --card-bg: #ffffff;
  --input-bg: #ffffff;
  --border: #e4e4e2;
  --border-strong: #cfcfcd;
  --invalid-bg: #ffe1e1;
  --invalid-fg: #b80707;
  --invalid-border: #f3a8a8;
  --empty-bg: #f4f4f4;
  --empty-fg: #999;
  --row-stripe: #fafafa;
  --header-bg: #f5f6f9;
  --ok-fg: #137a3b;
  --warn-fg: #b97a00;
  --font-sans: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic UI", "Segoe UI", sans-serif;
  --font-mono: "SF Mono", "Menlo", "Consolas", monospace;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body { font-family: var(--font-sans); background: var(--bg); color: var(--fg); line-height: 1.7; min-height: 100vh; }

.app-header {
  display: flex; align-items: center; gap: 14px;
  padding: 12px 16px; background: var(--card-bg); border-bottom: 1px solid var(--border);
}
.app-header h1 { font-size: 1rem; margin: 0; font-weight: 500; color: var(--fg-muted); }
.app-header .back { color: var(--fg); text-decoration: none; font-size: .9rem; }
.app-header .back:hover { color: var(--accent); }

.app-wrapper { max-width: 1100px; margin: 0 auto; padding: 28px 20px 60px; }
.lede { margin: 0 0 24px; color: var(--fg-muted); font-size: .95rem; }
.lede strong { color: var(--fg); }

.card {
  background: var(--card-bg); border: 1px solid var(--border); border-radius: 14px;
  padding: 22px 24px; box-shadow: 0 1px 3px rgba(0,0,0,.04); margin-bottom: 18px;
}
.card-title {
  display: flex; align-items: center; gap: 10px;
  margin: 0 0 14px; font-size: 1.05rem; color: var(--fg);
}
.card-sub { margin: -6px 0 14px; color: var(--fg-muted); font-size: .88rem; }
.card-sub strong { color: var(--fg); }
.step-num {
  display: inline-flex; align-items: center; justify-content: center;
  width: 26px; height: 26px; border-radius: 50%;
  background: var(--accent); color: #fff; font-size: .85rem; font-weight: 700;
}

.dropzone {
  border: 2px dashed var(--border-strong);
  border-radius: 12px;
  padding: 28px 16px;
  text-align: center;
  cursor: pointer;
  transition: border-color .15s ease, background .15s ease;
  background: #fcfcfc;
}
.dropzone:hover, .dropzone:focus { outline: none; border-color: var(--accent); background: #f5f8ff; }
.dropzone.dragging { border-color: var(--accent); background: #eef3ff; }
.dz-inner { display: flex; flex-direction: column; align-items: center; gap: 6px; }
.dz-icon { font-size: 1.6rem; color: var(--accent); }
.dz-main { font-size: 1rem; color: var(--fg); }
.dz-main strong { color: var(--accent); }
.dz-sub { font-size: .82rem; color: var(--fg-muted); }
.link-btn { background: none; border: none; color: var(--accent); cursor: pointer; padding: 4px 0; margin-top: 4px; font-size: .9rem; text-decoration: underline; }
.link-btn:hover { color: var(--accent-hover); }

.file-meta { margin-top: 12px; padding: 10px 14px; background: #f5f8ff; border: 1px solid #d6e2ff; border-radius: 8px; font-size: .9rem; color: var(--fg); }
.file-meta strong { font-family: var(--font-mono); }

.sheet-row, .range-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 14px; }
.field { display: flex; flex-direction: column; gap: 4px; }
.field > span { font-size: .82rem; color: var(--fg-muted); }
.field input, .field select {
  padding: 9px 12px; border: 1px solid var(--border); border-radius: 8px;
  font-size: .95rem; font-family: inherit; background: var(--input-bg); color: var(--fg);
  width: 100%; min-width: 0;
}
.field input:focus, .field select:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(42,91,255,.15); }

.rules-grid { display: flex; flex-direction: column; gap: 4px; }
.rule-toggle {
  display: flex; align-items: center; gap: 8px;
  font-size: .95rem; padding: 8px 0; color: var(--fg);
  cursor: pointer; user-select: none;
}
.rule-toggle input { width: 16px; height: 16px; accent-color: var(--accent); }
.rule-sub {
  display: flex; gap: 10px; flex-wrap: wrap;
  padding: 4px 0 12px 26px;
  border-bottom: 1px dashed var(--border);
}
.rule-sub input[type="text"] { flex: 1 1 280px; padding: 8px 10px; border: 1px solid var(--border); border-radius: 8px; font-family: var(--font-mono); font-size: .88rem; background: var(--input-bg); color: var(--fg); }
.rule-sub input[type="number"] { width: 100px; padding: 8px 10px; border: 1px solid var(--border); border-radius: 8px; font-size: .9rem; background: var(--input-bg); color: var(--fg); }
.inline { display: inline-flex; align-items: center; gap: 6px; font-size: .88rem; color: var(--fg-muted); }
.inline input[type="checkbox"], .inline input[type="radio"] { accent-color: var(--accent); }
.inline span { white-space: nowrap; }
.rule-empty { border: 1px solid var(--border); border-radius: 8px; padding: 10px 14px; margin-top: 10px; display: flex; flex-wrap: wrap; gap: 16px; }
.rule-empty legend { font-size: .82rem; color: var(--fg-muted); padding: 0 4px; }

.button-row { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 16px; }
button {
  padding: 10px 20px; border: none; border-radius: 10px; font-size: .95rem;
  font-weight: 600; font-family: inherit; cursor: pointer; transition: background-color .15s, color .15s, border-color .15s;
  background: var(--accent); color: #fff;
}
button:hover { background: var(--accent-hover); }
button.ghost { background: transparent; color: var(--accent); border: 1px solid var(--accent); }
button.ghost:hover { background: var(--accent); color: #fff; }
button.subtle { color: var(--fg-muted); border-color: var(--border-strong); }
button.subtle:hover { color: var(--fg); border-color: var(--fg-muted); background: transparent; }
button:disabled { opacity: .5; cursor: not-allowed; }

.stats-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 10px; margin-bottom: 16px;
}
.stat-tile {
  background: var(--header-bg); border: 1px solid var(--border); border-radius: 10px;
  padding: 12px 14px;
}
.stat-tile .stat-label { font-size: .75rem; color: var(--fg-muted); text-transform: uppercase; letter-spacing: .04em; }
.stat-tile .stat-value { font-size: 1.4rem; font-weight: 700; color: var(--fg); font-variant-numeric: tabular-nums; }
.stat-tile .stat-sub { font-size: .8rem; color: var(--fg-muted); margin-top: 2px; }
.stat-tile.invalid .stat-value { color: var(--invalid-fg); }
.stat-tile.valid .stat-value { color: var(--ok-fg); }

.col-stats { margin-bottom: 16px; }
.col-stats h3 { font-size: .9rem; margin: 0 0 6px; color: var(--fg-muted); font-weight: 600; }
.col-stats table { width: 100%; border-collapse: collapse; font-size: .85rem; }
.col-stats th, .col-stats td {
  padding: 6px 10px; border-bottom: 1px solid var(--border);
  text-align: right; font-variant-numeric: tabular-nums;
}
.col-stats th { background: var(--header-bg); color: var(--fg-muted); font-weight: 500; text-align: center; }
.col-stats td.col-name { text-align: left; font-weight: 600; color: var(--fg); }
.col-stats td.col-sample { text-align: left; color: var(--fg-muted); font-family: var(--font-mono); font-size: .78rem; max-width: 280px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.col-stats tr.has-invalid td.col-bad { color: var(--invalid-fg); font-weight: 700; }

.result-controls { display: flex; gap: 16px; align-items: center; flex-wrap: wrap; margin: 8px 0 12px; }
.legend { display: inline-flex; align-items: center; gap: 8px; font-size: .82rem; color: var(--fg-muted); }
.swatch { display: inline-block; width: 14px; height: 14px; border-radius: 3px; vertical-align: middle; margin-right: 2px; border: 1px solid var(--border); }
.swatch.invalid { background: var(--invalid-bg); border-color: var(--invalid-border); }
.swatch.empty { background: var(--empty-bg); }

.table-wrap { overflow: auto; max-height: 460px; border: 1px solid var(--border); border-radius: 8px; background: var(--card-bg); }
.data-table {
  border-collapse: separate; border-spacing: 0;
  font-family: var(--font-mono); font-size: .82rem;
  width: max-content; min-width: 100%;
}
.data-table th, .data-table td {
  border-right: 1px solid var(--border); border-bottom: 1px solid var(--border);
  padding: 4px 8px; white-space: nowrap; max-width: 260px; overflow: hidden; text-overflow: ellipsis;
  background: var(--card-bg);
}
.data-table thead th, .data-table th.row-num {
  background: var(--header-bg); color: var(--fg-muted);
  font-weight: 600; position: sticky; top: 0; z-index: 2;
  text-align: center; font-size: .75rem;
}
.data-table th.row-num {
  position: sticky; left: 0; top: auto; z-index: 1;
  text-align: right; min-width: 48px; font-variant-numeric: tabular-nums;
}
.data-table thead th.col-corner { position: sticky; left: 0; z-index: 3; }
.data-table thead th.col-header { font-size: .7rem; }
.data-table thead th.col-header .col-letter { color: var(--fg-faint); display: block; font-size: .65rem; }
.data-table tbody tr:nth-child(even) td { background: var(--row-stripe); }
.data-table tbody tr:nth-child(even) th.row-num { background: var(--row-stripe); }
.data-table td.cell-invalid { background: var(--invalid-bg); color: var(--invalid-fg); font-weight: 600; }
.data-table tbody tr:nth-child(even) td.cell-invalid { background: #ffd1d1; }
.data-table td.cell-empty { background: var(--empty-bg); color: var(--empty-fg); }
.data-table td.out-of-range { color: var(--fg-faint); }
.data-table tfoot td { padding: 8px; text-align: center; color: var(--fg-muted); font-size: .8rem; background: var(--header-bg); }

.action-heading { font-size: 1rem; margin: 22px 0 8px; color: var(--fg); }
.action-grid { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.action-grid .replace-row { display: flex; gap: 6px; align-items: stretch; }
.action-grid .replace-row input { padding: 8px 12px; border: 1px solid var(--border); border-radius: 8px; font-size: .9rem; background: var(--input-bg); color: var(--fg); width: 180px; }

.wp-content { margin: 40px 0 0; color: var(--fg-muted); line-height: 1.9; }
.wp-content h2 {
  font-size: 1.1rem; color: var(--fg); margin: 24px 0 10px;
  padding-top: 16px; border-top: 1px solid var(--border);
}
.wp-content p { margin: 0 0 12px; }
.wp-content ul { padding-left: 1.4em; }
.wp-content code { background: #eef; padding: 1px 6px; border-radius: 3px; font-size: .88em; font-family: var(--font-mono); }
.wp-content strong { color: var(--fg); }

@media (max-width: 720px) {
  .app-wrapper { padding: 20px 14px 40px; }
  .card { padding: 18px 16px; }
  .sheet-row, .range-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .action-grid .replace-row input { width: 130px; }
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #121212;
  --card-bg: #1d1d1d;
  --input-bg: #2a2a2a;
  --fg: #f0f0f0;
  --fg-muted: #a0a0a0;
  --fg-faint: #666;
  --border: #2a2a2a;
  --border-strong: #3a3a3a;
  --row-stripe: #181818;
  --header-bg: #232323;
  --invalid-bg: #4a1a1a;
  --invalid-fg: #ff8c8c;
  --invalid-border: #6a2a2a;
  --empty-bg: #232323;
  --empty-fg: #666;
  --accent: #5a82ff;
  --accent-hover: #2a5bff;
  --ok-fg: #4ade80;
}
:root[data-theme="dark"] .dropzone { background: #1a1a1a; }
:root[data-theme="dark"] .dropzone:hover { background: #1f2436; }
:root[data-theme="dark"] .file-meta { background: #1f2436; border-color: #2c3a5a; }
:root[data-theme="dark"] .data-table tbody tr:nth-child(even) td.cell-invalid { background: #5a2222; }
:root[data-theme="dark"] .wp-content code { background: #2a2a3a; color: #e0e0ff; }

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #121212;
    --card-bg: #1d1d1d;
    --input-bg: #2a2a2a;
    --fg: #f0f0f0;
    --fg-muted: #a0a0a0;
    --fg-faint: #666;
    --border: #2a2a2a;
    --border-strong: #3a3a3a;
    --row-stripe: #181818;
    --header-bg: #232323;
    --invalid-bg: #4a1a1a;
    --invalid-fg: #ff8c8c;
    --invalid-border: #6a2a2a;
    --empty-bg: #232323;
    --empty-fg: #666;
    --accent: #5a82ff;
    --accent-hover: #2a5bff;
    --ok-fg: #4ade80;
  }
  :root:not([data-theme="light"]) .dropzone { background: #1a1a1a; }
  :root:not([data-theme="light"]) .dropzone:hover { background: #1f2436; }
  :root:not([data-theme="light"]) .file-meta { background: #1f2436; border-color: #2c3a5a; }
  :root:not([data-theme="light"]) .data-table tbody tr:nth-child(even) td.cell-invalid { background: #5a2222; }
  :root:not([data-theme="light"]) .wp-content code { background: #2a2a3a; color: #e0e0ff; }
}

.owt-theme-toggle {
  position: fixed; top: 10px; right: 12px; z-index: 9999;
  display: inline-flex; align-items: center; justify-content: center;
  width: 36px; height: 36px; padding: 0;
  border: 1px solid rgba(127, 127, 127, 0.4); border-radius: 999px;
  background: rgba(255, 255, 255, 0.85); color: #333;
  cursor: pointer; font-size: 1.05rem; line-height: 1;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.06), 0 4px 12px rgba(0, 0, 0, 0.08);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
  transition: background .15s ease, border-color .15s ease, transform .15s ease;
}
.owt-theme-toggle:hover { transform: translateY(-1px); border-color: rgba(127, 127, 127, 0.7); }
.owt-theme-toggle:focus-visible { outline: 2px solid currentColor; outline-offset: 2px; }
:root[data-theme="dark"] .owt-theme-toggle { background: rgba(40, 40, 40, 0.85); color: #eee; border-color: rgba(200, 200, 200, 0.25); }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .owt-theme-toggle { background: rgba(40, 40, 40, 0.85); color: #eee; border-color: rgba(200, 200, 200, 0.25); }
}
@media print { .owt-theme-toggle { display: none; } }