:root {
  /* Neutral tool chrome */
  --bg-app:    #fbfaf8;   /* app background (near-white) */
  --bg-viewer: #eeedea;   /* PDF pane — slight gray to let the page pop */
  --bg-panel:  #f5f4f1;   /* right panel — subtle contrast */
  --card:      #ffffff;
  --ink:       #101010;
  --ink-2:     #2a2a28;
  --muted:     #6c6b66;
  --rule:      #e2e0d9;
  --rule-soft: #ecebe4;

  /* Accent — used sparingly: logo flourish, hover/focus, badges */
  --accent:       #5b1f22;
  --accent-2:     #7a2a2e;
  --accent-soft:  #f4ebec;

  --warn: #8a5a11;
  --err:  #9b2c2c;
  --ok:   #1f5533;

  --serif: "Fraunces", "Iowan Old Style", "Georgia", "Hiragino Mincho ProN", "YuMincho", serif;
  --sans: -apple-system, BlinkMacSystemFont, "Inter", "Hiragino Sans", "Yu Gothic UI", system-ui, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "JetBrains Mono", Menlo, monospace;

  --header-h: 60px;
  --radius: 5px;
  --shadow-1: 0 1px 2px rgba(16,16,16,0.05);
  --shadow-2: 0 3px 14px rgba(16,16,16,0.08);
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

html, body {
  margin: 0;
  height: 100dvh;
  overflow: hidden;              /* no page-level scroll, panes scroll internally */
  background: var(--bg-app);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 13.5px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
body {
  display: flex;
  flex-direction: column;
}

button, input, select, textarea { font: inherit; color: inherit; }

kbd {
  display: inline-block;
  padding: 0 0.35em;
  border: 1px solid var(--rule);
  border-bottom-width: 2px;
  border-radius: 3px;
  background: var(--card);
  font-family: var(--mono);
  font-size: 0.75em;
  color: var(--ink-2);
}

/* ---------- Header ---------- */

header {
  flex: 0 0 var(--header-h);
  border-bottom: 1px solid var(--rule);
  background: var(--card);
  display: flex;
  align-items: center;
  padding: 0 1.1rem;
  gap: 1.1rem;
  z-index: 5;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
}
.brand .logo {
  font-family: var(--serif);
  font-optical-sizing: auto;
  font-weight: 700;
  font-size: 1.75rem;
  letter-spacing: -0.015em;
  line-height: 1;
  color: var(--ink);
  font-variation-settings: "opsz" 48, "SOFT" 30;
}
.brand .sub {
  font-size: 0.8rem;
  color: var(--muted);
  letter-spacing: 0.005em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  padding-left: 0.75rem;
  border-left: 1px solid var(--rule);
}

.toolbar {
  flex: 1;
  display: flex;
  align-items: center;
  gap: 0.65rem;
  flex-wrap: wrap;
}
.toolbar .spacer { flex: 1; }

.row {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.82rem;
  color: var(--muted);
  font-family: var(--mono);
  letter-spacing: 0.05em;
  text-transform: lowercase;
}
.row select {
  padding: 0.35rem 0.55rem;
  font-size: 0.88rem;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--card);
  color: var(--ink);
  font-family: var(--sans);
  text-transform: none;
  letter-spacing: 0;
  transition: border-color 0.12s, box-shadow 0.12s;
}
.row select:hover { border-color: var(--accent); }
.row select:focus-visible {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.file-btn {
  display: inline-flex;
  align-items: center;
  padding: 0.48rem 1rem;
  background: var(--ink);
  color: #ffffff;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 0.88rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  transition: background 0.12s, transform 0.08s;
}
.file-btn:hover { background: #000; }
.file-btn:active { transform: translateY(1px); }

button.ghost {
  background: transparent;
  color: var(--ink-2);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: 0.4rem 0.85rem;
  font-size: 0.82rem;
  cursor: pointer;
  transition: background 0.12s, border-color 0.12s, color 0.12s;
}
button.ghost:hover {
  background: var(--card);
  border-color: var(--accent);
  color: var(--accent);
}

.doc-meta {
  font-size: 0.82rem;
  color: var(--muted);
  font-family: var(--mono);
  max-width: 22em;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ---------- Main 2-pane layout ---------- */

main {
  flex: 1 1 auto;
  min-height: 0;                 /* required for nested scroll areas to behave */
  display: grid;
  grid-template-columns: 1fr 420px;
}

.viewer {
  overflow: auto;
  background: var(--bg-viewer);
  padding: 1.25rem;
  position: relative;
  outline: 2px dashed transparent;
  outline-offset: -8px;
  transition: outline-color 0.12s;
}
.viewer.dragover { outline-color: var(--accent-2); }

/* Empty state */
.drop-hint {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100%;
  padding: 2rem;
}
.drop-hint-inner {
  max-width: 440px;
  text-align: center;
  color: var(--ink-2);
  background: var(--card);
  border: 1px solid var(--rule-soft);
  border-radius: 10px;
  padding: 2.5rem 2rem 2rem;
  box-shadow: var(--shadow-2);
}
.drop-hint-inner .hero {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 4rem;
  line-height: 1;
  color: var(--ink);
  letter-spacing: -0.02em;
  margin-bottom: 0.85rem;
  font-variation-settings: "opsz" 144, "SOFT" 60;
}
.drop-hint-inner p {
  margin: 0.4rem 0;
  font-size: 0.9rem;
}
.drop-hint-inner p.hint {
  color: var(--muted);
  font-size: 0.82rem;
}

.pages {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.2rem;
}

.page {
  position: relative;
  background: #fff;
  box-shadow: var(--shadow-2);
  border-radius: 2px;
}
.page canvas { display: block; }

/* PDF.js v4 text layer */
.textLayer {
  position: absolute; inset: 0;
  overflow: hidden;
  opacity: 1;
  line-height: 1;
  text-align: initial;
  forced-color-adjust: none;
  transform-origin: 0 0;
  z-index: 2;
  user-select: text;
  -webkit-user-select: text;
}
.textLayer span,
.textLayer br {
  color: transparent;
  position: absolute;
  white-space: pre;
  cursor: text;
  transform-origin: 0% 0%;
}
.textLayer span.markedContent { top: 0; height: 0; }
.textLayer ::selection      { background: rgba(91, 31, 34, 0.22); }
.textLayer ::-moz-selection { background: rgba(91, 31, 34, 0.22); }

/* ---------- Right panel (glosses) ---------- */

.panel {
  border-left: 1px solid var(--rule);
  background: var(--bg-panel);
  display: flex;
  flex-direction: column;
  min-height: 0;
}

.panel-head {
  padding: 0.9rem 1.1rem 0.7rem;
  border-bottom: 1px solid var(--rule);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.panel-head h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.02rem;
  letter-spacing: 0.01em;
  margin: 0;
  color: var(--ink);
  font-variation-settings: "opsz" 24, "SOFT" 30;
}
.muted {
  color: var(--muted);
  font-size: 0.72rem;
  font-family: var(--mono);
}

.current {
  padding: 0.7rem 1.1rem;
  border-bottom: 1px solid var(--rule-soft);
  min-height: 2.4em;
  font-size: 0.82rem;
  color: var(--muted);
  font-style: italic;
}
.current.active {
  color: var(--ink-2);
  font-style: normal;
}

.history {
  list-style: none;
  margin: 0;
  padding: 0;
  overflow-y: auto;
  flex: 1;
}
.history li {
  padding: 0.85rem 1.1rem;
  border-bottom: 1px solid var(--rule-soft);
  font-size: 0.9rem;
  background: var(--bg-panel);
  transition: background 0.12s;
}
.history li:hover { background: #fff; }

.history li .head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.45rem;
}
.history li .time {
  font-size: 0.7rem;
  color: var(--muted);
  font-family: var(--mono);
}
.history li .badge {
  display: inline-block;
  padding: 0.05rem 0.5rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.68rem;
  font-family: var(--mono);
  letter-spacing: 0.02em;
}
.history li .badge.cache { background: #e4f1e8; color: var(--ok); }
.history li .badge.err   { background: #fbe6e6; color: var(--err); }

.history li .src {
  color: var(--muted);
  font-size: 0.78rem;
  margin-bottom: 0.4rem;
  max-height: 3.8em;
  overflow: hidden;
  position: relative;
  border-left: 2px solid var(--rule);
  padding-left: 0.6rem;
  cursor: pointer;
}
.history li .src::after {
  content: "";
  position: absolute;
  left: 0.6rem; right: 0; bottom: 0;
  height: 1.2em;
  background: linear-gradient(to bottom, transparent, var(--bg-panel));
  pointer-events: none;
}
.history li:hover .src::after {
  background: linear-gradient(to bottom, transparent, #fff);
}
.history li .src.expanded { max-height: none; }
.history li .src.expanded::after { display: none; }

.history li .tr {
  font-family: var(--serif);
  font-variation-settings: "opsz" 14;
  font-size: 1rem;
  line-height: 1.65;
  color: var(--ink);
  white-space: pre-wrap;
  word-break: break-word;
}

.history li.loading .tr { color: var(--muted); }
.history li.loading .tr::after {
  content: "⋯";
  display: inline-block;
  margin-left: 0.3em;
  animation: dots 1.2s infinite steps(3);
}
@keyframes dots {
  0%   { content: "⋯"; }
  33%  { content: "⋯⋯"; }
  66%  { content: "⋯⋯⋯"; }
  100% { content: "⋯"; }
}

/* Scrollbars (webkit) */
.history::-webkit-scrollbar,
.viewer::-webkit-scrollbar { width: 10px; height: 10px; }
.history::-webkit-scrollbar-thumb,
.viewer::-webkit-scrollbar-thumb {
  background: var(--rule);
  border-radius: 10px;
  border: 2px solid var(--bg-viewer);
}
.history::-webkit-scrollbar-thumb:hover,
.viewer::-webkit-scrollbar-thumb:hover { background: var(--muted); }

/* ---------- Icon button ---------- */

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px; height: 32px;
  background: transparent;
  color: var(--ink-2);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.12s, border-color 0.12s, color 0.12s;
}
.icon-btn:hover {
  background: var(--card);
  border-color: var(--accent);
  color: var(--accent);
}
.icon-btn.close {
  border: 0;
  color: var(--muted);
  font-size: 1.1rem;
}
.icon-btn.close:hover { color: var(--ink); background: transparent; }

/* ---------- Settings modal ---------- */

.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(16, 16, 16, 0.32);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  z-index: 100;
  animation: fade-in 0.12s ease-out;
}
@keyframes fade-in { from { opacity: 0; } to { opacity: 1; } }

.modal {
  background: var(--card);
  border-radius: 8px;
  box-shadow: 0 20px 50px rgba(16,16,16,0.22);
  width: min(520px, 100%);
  max-height: 85vh;
  overflow: auto;
  border: 1px solid var(--rule);
}
.modal-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--rule-soft);
}
.modal-head h3 {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.005em;
}
.modal-help {
  margin: 0;
  padding: 0.6rem 0 0;
  font-size: 0.8rem;
  color: var(--muted);
  line-height: 1.65;
}
.modal-help code {
  font-family: var(--mono);
  font-size: 0.85em;
  background: var(--bg-app);
  padding: 0.05rem 0.3rem;
  border-radius: 3px;
  border: 1px solid var(--rule-soft);
}

.modal-section {
  padding: 0.85rem 1.25rem 0.75rem;
  border-bottom: 1px solid var(--rule-soft);
}
.switch {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  user-select: none;
}
.switch input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--accent);
  cursor: pointer;
}
.switch span {
  font-size: 0.9rem;
  color: var(--ink);
}

.settings-form {
  padding: 0.85rem 1.25rem 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}
.settings-form:empty {
  display: none;
}
.modal-foot {
  padding: 0.75rem 1.25rem;
  border-top: 1px solid var(--rule-soft);
  min-height: 2.2em;
  font-size: 0.8rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.75rem;
}
.modal-foot .ok  { color: var(--ok); }
.modal-foot .err { color: var(--err); }
.modal-foot button.ghost.danger {
  color: var(--err);
  border-color: var(--rule);
  padding: 0.3rem 0.7rem;
  font-size: 0.78rem;
}
.modal-foot button.ghost.danger:hover {
  border-color: var(--err);
  background: #fbe6e6;
}

/* Per-engine settings row */
.setting {
  padding: 0.9rem 1rem;
  border: 1px solid var(--rule-soft);
  border-radius: 6px;
  background: var(--bg-app);
}
.setting-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.6rem;
  gap: 0.75rem;
}
.setting-title {
  font-weight: 600;
  font-size: 0.92rem;
  letter-spacing: 0.005em;
}
.setting-status {
  font-size: 0.72rem;
  font-family: var(--mono);
  padding: 0.1rem 0.5rem;
  border-radius: 999px;
}
.setting-status.ok  { background: #e4f1e8; color: var(--ok); }
.setting-status.off { background: #efede6; color: var(--muted); }

.setting-row {
  display: flex;
  gap: 0.5rem;
  align-items: center;
}
.setting-row input {
  flex: 1;
  padding: 0.45rem 0.6rem;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--card);
  font-family: var(--mono);
  font-size: 0.85rem;
  color: var(--ink);
  transition: border-color 0.12s, box-shadow 0.12s;
}
.setting-row input:focus-visible {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.setting-row button.primary {
  padding: 0.45rem 0.9rem;
  background: var(--ink);
  color: #fff;
  border: 0;
  border-radius: var(--radius);
  font-size: 0.82rem;
  cursor: pointer;
  transition: background 0.12s;
}
.setting-row button.primary:hover { background: #000; }
.setting-row button.ghost.danger {
  color: var(--err);
  border-color: var(--rule);
}
.setting-row button.ghost.danger:hover {
  border-color: var(--err);
  background: #fbe6e6;
  color: var(--err);
}

.setting-note {
  margin: 0.5rem 0 0;
  font-size: 0.78rem;
  color: var(--warn);
}
.setting-link {
  display: inline-block;
  margin-top: 0.55rem;
  font-size: 0.78rem;
  color: var(--accent);
  text-decoration: none;
}
.setting-link:hover { text-decoration: underline; }

.err-msg { color: var(--err); font-size: 0.85rem; }