:root {
  color-scheme: light;
  --accent: #4f46e5;
  --accent-hover: #4338ca;
  --accent-soft: #eef2ff;
  --accent-border: #c7d2fe;
  --fg: #1f2937;
  --fg-muted: #6b7280;
  --fg-faint: #9ca3af;
  --bg: #f5f7fb;
  --card-bg: #ffffff;
  --input-bg: #ffffff;
  --border: #e5e7eb;
  --border-strong: #d1d5db;
  --header-bg: #f5f7fb;
  --row-stripe: #fafbff;
  --ok-fg: #10b981;
  --warn-fg: #f59e0b;
  --c-error: #ef4444;
  --added-bg: #ecfdf5;
  --added-fg: #047857;
  --added-border: #a7f3d0;
  --removed-bg: #fef2f2;
  --removed-fg: #b91c1c;
  --removed-border: #fecaca;
  --modified-bg: #fef3c7;
  --modified-fg: #92400e;
  --modified-border: #fde68a;
  --side-a-color: #6366f1;
  --side-b-color: #10b981;
  --shadow-card: 0 2px 20px rgba(79, 70, 229, 0.08);
  --radius-lg: 16px;
  --radius-md: 12px;
  --radius-sm: 8px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", "Yu Gothic UI", "Segoe UI", sans-serif;
  --font-mono: "SF Mono", "Menlo", "Consolas", monospace;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
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 { margin: 0; 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: var(--radius-lg);
  padding: 22px 24px; box-shadow: var(--shadow-card); 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;
}

.two-up { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.side { display: flex; flex-direction: column; gap: 8px; }
.side-label {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: .88rem; color: var(--fg-muted); font-weight: 600;
}
.side-dot {
  display: inline-block; width: 12px; height: 12px; border-radius: 50%;
}
.side-dot.side-a { background: var(--side-a-color); }
.side-dot.side-b { background: var(--side-b-color); }

.dropzone {
  border: 2px dashed var(--border-strong);
  border-radius: var(--radius-md); padding: 22px 14px; text-align: center; cursor: pointer;
  transition: border-color .15s ease, background .15s ease;
  background: var(--bg);
}
.dropzone:hover, .dropzone:focus { outline: none; border-color: var(--accent); background: var(--accent-soft); }
.dropzone.dragging { border-color: var(--accent); background: var(--accent-soft); }
.dz-inner { display: flex; flex-direction: column; align-items: center; gap: 4px; }
.dz-icon { font-size: 1.4rem; color: var(--accent); }
.dz-main { font-size: .95rem; color: var(--fg); }
.dz-sub { font-size: .78rem; color: var(--fg-muted); }

.file-meta { padding: 8px 12px; background: var(--accent-soft); border: 1px solid var(--accent-border); border-radius: var(--radius-sm); font-size: .85rem; color: var(--fg); }
.file-meta strong { font-family: var(--font-mono); }
.file-meta .dot { color: var(--fg-faint); margin: 0 6px; }

.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: var(--radius-sm);
  font-size: .95rem; font-family: inherit; background: var(--input-bg); color: var(--fg);
  width: 100%; min-width: 0;
}
.field input:focus, .field select:focus, .field select:not([disabled]):focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(79,70,229,.15); }
.field select[disabled] { background: var(--bg); color: var(--fg-faint); cursor: not-allowed; }
.field.shrink { max-width: 320px; }

.opt-row { display: flex; gap: 14px; align-items: flex-end; margin-top: 14px; flex-wrap: wrap; }
.link-btn { background: none; border: none; color: var(--accent); cursor: pointer; padding: 4px 0; font-size: .9rem; text-decoration: underline; }
.link-btn:hover { color: var(--accent-hover); }

.help-mark {
  display: inline-flex; align-items: center; justify-content: center;
  width: 16px; height: 16px; margin-left: 6px; padding: 0;
  background: var(--fg-muted); color: #fff;
  border: none; border-radius: 50%;
  font-size: .7rem; font-weight: 700; line-height: 1;
  cursor: help; vertical-align: middle;
  position: relative;
}
.help-mark:hover, .help-mark:focus { background: var(--accent); outline: none; }
.help-mark::after {
  content: attr(data-help);
  position: absolute; top: calc(100% + 8px); left: 50%; transform: translateX(-50%);
  white-space: pre-line; width: max-content; max-width: 300px;
  padding: 10px 12px; border-radius: 8px;
  background: #2b2b2b; color: #fff; font-size: .78rem; font-weight: 400;
  text-align: left; line-height: 1.5;
  box-shadow: 0 4px 12px rgba(0,0,0,.18);
  pointer-events: none; opacity: 0; visibility: hidden;
  transition: opacity .15s ease, visibility .15s ease;
  z-index: 100;
}
.help-mark::before {
  content: ''; position: absolute; top: calc(100% + 2px); left: 50%; transform: translateX(-50%);
  border: 6px solid transparent; border-bottom-color: #2b2b2b;
  pointer-events: none; opacity: 0; visibility: hidden;
  transition: opacity .15s ease, visibility .15s ease;
  z-index: 101;
}
.help-mark:hover::after, .help-mark:focus::after,
.help-mark:hover::before, .help-mark:focus::before {
  opacity: 1; visibility: visible;
}

.rules-grid { display: flex; flex-direction: column; gap: 12px; }
.opt-fieldset {
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 10px 14px; margin: 0;
  display: flex; flex-wrap: wrap; gap: 14px; align-items: center;
}
.opt-fieldset legend { font-size: .82rem; color: var(--fg-muted); padding: 0 4px; }
.inline { display: inline-flex; align-items: center; gap: 6px; font-size: .9rem; color: var(--fg); }
.inline input[type="checkbox"], .inline input[type="radio"] { accent-color: var(--accent); width: 16px; height: 16px; }
.inline input[type="text"] {
  padding: 6px 10px; border: 1px solid var(--border); border-radius: var(--radius-sm);
  font-size: .88rem; font-family: var(--font-mono); background: var(--input-bg); color: var(--fg);
}

.threshold-row { padding: 4px 0; }
.thr { gap: 10px; }
.thr input[type="range"] { width: 200px; accent-color: var(--accent); }
.thr-value { font-family: var(--font-mono); font-variant-numeric: tabular-nums; color: var(--fg-muted); min-width: 3em; }

.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:disabled { opacity: .5; cursor: not-allowed; }
button:disabled:hover { background: var(--accent); }
button.ghost:disabled:hover { background: transparent; color: var(--accent); }

.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.matched .stat-value { color: var(--fg); }
.stat-tile.modified .stat-value { color: var(--modified-fg); }
.stat-tile.aonly .stat-value { color: var(--removed-fg); }
.stat-tile.bonly .stat-value { color: var(--added-fg); }

.result-controls { display: flex; gap: 16px; align-items: center; flex-wrap: wrap; margin: 8px 0 12px; }
.legend { display: inline-flex; align-items: center; gap: 10px; font-size: .82rem; color: var(--fg-muted); flex-wrap: wrap; }
.swatch { display: inline-block; width: 14px; height: 14px; border-radius: 3px; vertical-align: middle; margin-right: 2px; border: 1px solid var(--border); }
.swatch.matched { background: var(--card-bg); }
.swatch.modified { background: var(--modified-bg); border-color: var(--modified-border); }
.swatch.aonly { background: var(--removed-bg); border-color: var(--removed-border); }
.swatch.bonly { background: var(--added-bg); border-color: var(--added-border); }

.compare-split {
  display: grid; grid-template-columns: 1fr 1fr; gap: 12px; align-items: stretch;
}
.side-pane { display: flex; flex-direction: column; min-width: 0; }
.side-pane-label {
  padding: 8px 12px; font-size: .85rem; font-weight: 600; color: var(--fg);
  border: 1px solid var(--border); border-bottom: 0;
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.side-pane-label.is-a { background: rgba(99, 102, 241, .12); }
.side-pane-label.is-b { background: rgba(16, 185, 129, .12); }
.side-pane-label strong { font-family: var(--font-mono); font-weight: 700; }

.side-scroll {
  overflow: auto; max-height: 70vh;
  border: 1px solid var(--border);
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  background: var(--card-bg);
}
.compare-table {
  border-collapse: separate; border-spacing: 0;
  font-family: var(--font-mono); font-size: .82rem;
  width: max-content; min-width: 100%;
}
.compare-table th, .compare-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); vertical-align: top; line-height: 1.5;
}
.compare-table thead th {
  background: var(--header-bg); color: var(--fg-muted);
  font-weight: 600; position: sticky; top: 0; z-index: 2;
  text-align: center; font-size: .75rem;
}
.compare-table thead th.col-header .col-letter { font-size: .65rem; color: var(--fg-faint); display: block; }
.compare-table .row-num {
  background: var(--header-bg); color: var(--fg-muted);
  text-align: right; min-width: 44px; font-variant-numeric: tabular-nums;
  font-size: .75rem;
  position: sticky; left: 0; z-index: 1;
}
.compare-table thead th.row-num { z-index: 3; }
.compare-table tbody tr.matched td:not(.row-num) { background: var(--card-bg); }
.compare-table tbody tr.matched.zebra td:not(.row-num) { background: var(--row-stripe); }
.compare-table tbody tr.modified .row-num.row-num-mod { color: var(--modified-fg); font-weight: 700; }
.compare-table tbody tr td.cell-mod { background: var(--modified-bg); color: var(--modified-fg); }
.side-scroll.is-a tbody tr.aonly .row-num { color: var(--removed-fg); font-weight: 700; }
.side-scroll.is-a tbody tr.aonly td:not(.row-num) { background: var(--removed-bg); color: var(--removed-fg); }
.side-scroll.is-a tbody tr.bonly td { background: repeating-linear-gradient(45deg, var(--bg), var(--bg) 4px, var(--border) 4px, var(--border) 5px); color: transparent; }
.side-scroll.is-a tbody tr.bonly th.row-num { background: var(--header-bg); color: transparent; }
.side-scroll.is-b tbody tr.bonly .row-num { color: var(--added-fg); font-weight: 700; }
.side-scroll.is-b tbody tr.bonly td:not(.row-num) { background: var(--added-bg); color: var(--added-fg); }
.side-scroll.is-b tbody tr.aonly td { background: repeating-linear-gradient(45deg, var(--bg), var(--bg) 4px, var(--border) 4px, var(--border) 5px); color: transparent; }
.side-scroll.is-b tbody tr.aonly th.row-num { background: var(--header-bg); color: transparent; }

.compare-table .char-removed { background: rgba(239, 68, 68, .25); color: var(--removed-fg); border-radius: 2px; padding: 0 1px; }
.compare-table .char-added { background: rgba(16, 185, 129, .25); color: var(--added-fg); border-radius: 2px; padding: 0 1px; }

.compare-table.hide-matched tbody tr.matched { display: none; }
.compare-table tfoot td { padding: 8px; text-align: center; color: var(--fg-muted); font-size: .8rem; background: var(--header-bg); }
.empty-state { padding: 28px 14px; text-align: center; color: var(--fg-muted); font-size: .9rem; }

.action-heading { font-size: 1rem; margin: 22px 0 8px; color: var(--fg); }

.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 h3 { font-size: .98rem; color: var(--fg); margin: 18px 0 6px; font-weight: 600; }
.wp-content p { margin: 0 0 12px; }
.wp-content ul { padding-left: 1.4em; }
.wp-content code { background: var(--accent-soft); color: var(--fg); padding: 1px 6px; border-radius: 3px; font-size: .88em; font-family: var(--font-mono); }
.wp-content strong { color: var(--fg); }

@media (max-width: 880px) {
  .two-up { grid-template-columns: 1fr; }
  .opt-fieldset { gap: 10px; }
}
@media (max-width: 720px) {
  .app-wrapper { padding: 20px 14px 40px; }
  .card { padding: 18px 16px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .side-scroll { max-height: 60vh; }
  .compare-table th, .compare-table td { padding: 3px 6px; font-size: .76rem; max-width: 180px; }
  .compare-split { gap: 6px; }
  .help-mark::after { left: auto; right: 0; transform: none; max-width: 240px; }
  .help-mark::before { left: auto; right: 6px; transform: none; }
  .thr input[type="range"] { width: 140px; }
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #14141c;
  --card-bg: #1d1d28;
  --input-bg: #25253a;
  --fg: #f0f0f5;
  --fg-muted: #a0a0b0;
  --fg-faint: #6a6a78;
  --border: #2a2a38;
  --border-strong: #3a3a4a;
  --row-stripe: #1a1a24;
  --header-bg: #232333;
  --accent: #8b80ff;
  --accent-hover: #6c63ff;
  --accent-soft: #2a2348;
  --accent-border: #4f46e5;
  --ok-fg: #4ade80;
  --added-bg: #14352a;
  --added-fg: #5eead4;
  --added-border: #1e6b53;
  --removed-bg: #3f1a1f;
  --removed-fg: #fca5a5;
  --removed-border: #7f1d1d;
  --modified-bg: #4a3a14;
  --modified-fg: #fde68a;
  --modified-border: #92400e;
  --side-a-color: #8b80ff;
  --side-b-color: #4ade80;
  --shadow-card: 0 2px 20px rgba(0, 0, 0, 0.4);
}
:root[data-theme="dark"] .dropzone { background: #1a1a24; }
:root[data-theme="dark"] .dropzone:hover { background: #2a2348; }
:root[data-theme="dark"] .file-meta { background: #2a2348; border-color: #4f46e5; }
:root[data-theme="dark"] .wp-content code { background: #2a2a3a; color: #e0e0ff; }
:root[data-theme="dark"] .compare-table thead th.side-header.side-a-h { background: rgba(139, 128, 255, .18); }
:root[data-theme="dark"] .compare-table thead th.side-header.side-b-h { background: rgba(74, 222, 128, .18); }
:root[data-theme="dark"] .compare-table .char-removed { background: rgba(252, 165, 165, .25); color: var(--removed-fg); }
:root[data-theme="dark"] .compare-table .char-added { background: rgba(94, 234, 212, .25); color: var(--added-fg); }

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #14141c;
    --card-bg: #1d1d28;
    --input-bg: #25253a;
    --fg: #f0f0f5;
    --fg-muted: #a0a0b0;
    --fg-faint: #6a6a78;
    --border: #2a2a38;
    --border-strong: #3a3a4a;
    --row-stripe: #1a1a24;
    --header-bg: #232333;
    --accent: #8b80ff;
    --accent-hover: #6c63ff;
    --accent-soft: #2a2348;
    --accent-border: #4f46e5;
    --ok-fg: #4ade80;
    --added-bg: #14352a;
    --added-fg: #5eead4;
    --added-border: #1e6b53;
    --removed-bg: #3f1a1f;
    --removed-fg: #fca5a5;
    --removed-border: #7f1d1d;
    --modified-bg: #4a3a14;
    --modified-fg: #fde68a;
    --modified-border: #92400e;
    --side-a-color: #8b80ff;
    --side-b-color: #4ade80;
    --shadow-card: 0 2px 20px rgba(0, 0, 0, 0.4);
  }
  :root:not([data-theme="light"]) .dropzone { background: #1a1a24; }
  :root:not([data-theme="light"]) .dropzone:hover { background: #2a2348; }
  :root:not([data-theme="light"]) .file-meta { background: #2a2348; border-color: #4f46e5; }
  :root:not([data-theme="light"]) .wp-content code { background: #2a2a3a; color: #e0e0ff; }
  :root:not([data-theme="light"]) .compare-table thead th.side-header.side-a-h { background: rgba(139, 128, 255, .18); }
  :root:not([data-theme="light"]) .compare-table thead th.side-header.side-b-h { background: rgba(74, 222, 128, .18); }
  :root:not([data-theme="light"]) .compare-table .char-removed { background: rgba(252, 165, 165, .25); color: var(--removed-fg); }
  :root:not([data-theme="light"]) .compare-table .char-added { background: rgba(94, 234, 212, .25); color: var(--added-fg); }
}

.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; } }