:root {
  --paper: #f3efe5;
  --ink: #171816;
  --muted: #67665f;
  --line: #cbc4b5;
  --accent: #a43d28;
  --pass: #2e6549;
  --review: #9b651d;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Songti SC", "Noto Serif CJK SC", serif;
}

button { font: inherit; }

.masthead {
  max-width: 1440px;
  margin: 0 auto;
  padding: 48px 32px 28px;
  display: flex;
  justify-content: space-between;
  align-items: end;
  border-bottom: 1px solid var(--ink);
}

.eyebrow, .page-kicker {
  margin: 0 0 8px;
  color: var(--accent);
  font: 700 12px/1.2 ui-monospace, monospace;
  letter-spacing: .14em;
}

h1 { margin: 0; font-size: clamp(32px, 5vw, 68px); line-height: .98; font-weight: 700; }
.dek { margin: 14px 0 0; color: var(--muted); font-size: 16px; }
.progress { padding-bottom: 6px; white-space: nowrap; color: var(--muted); }
.progress strong { color: var(--ink); font-size: 32px; }

main { max-width: 1440px; margin: 0 auto; padding: 22px 32px 48px; }

.page-strip { display: flex; gap: 8px; overflow-x: auto; padding: 0 0 20px; }
.page-strip button, .view-controls button, .reader-foot button {
  border: 1px solid var(--line);
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  transition: background .18s ease, color .18s ease, border-color .18s ease;
}
.page-strip button { min-width: 52px; padding: 9px 10px; border-radius: 999px; font: 650 12px/1 ui-monospace, monospace; }
.page-strip button:hover, .page-strip button:focus-visible, .page-strip button.active { background: var(--ink); border-color: var(--ink); color: var(--paper); outline: none; }
.page-strip button.review::after { content: "•"; margin-left: 4px; color: #e3a83e; }

.reader { border-top: 1px solid var(--line); }
.reader-head { display: flex; justify-content: space-between; gap: 20px; align-items: start; padding: 24px 0 18px; }
h2 { margin: 0; font-size: clamp(22px, 3vw, 38px); font-weight: 600; }
.status { padding: 7px 10px; border-radius: 2px; color: white; font: 700 11px/1 ui-monospace, monospace; letter-spacing: .06em; }
.status.pass { background: var(--pass); }
.status.needs_review { background: var(--review); }

.view-controls { display: flex; gap: 0; margin: 0 0 18px; }
.view-controls button { padding: 9px 14px; border-right-width: 0; }
.view-controls button:first-child { border-radius: 3px 0 0 3px; }
.view-controls button:last-child { border-right-width: 1px; border-radius: 0 3px 3px 0; }
.view-controls button.active { background: var(--accent); border-color: var(--accent); color: white; }
.view-controls button:disabled { opacity: .35; cursor: not-allowed; }

.pages { display: grid; gap: 18px; align-items: start; }
.pages.compare { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.pages.original .translated-panel, .pages.original .gpt-panel,
.pages.translated .original-panel, .pages.translated .gpt-panel,
.pages.gpt .original-panel, .pages.gpt .translated-panel { display: none; }
.pages.compare .gpt-panel { display: none; }
figure { margin: 0; min-width: 0; }
figcaption { margin-bottom: 8px; color: var(--muted); font: 650 11px/1.2 ui-monospace, monospace; text-transform: uppercase; }
figure img { display: block; width: 100%; max-height: 78vh; object-fit: contain; object-position: top center; background: #fff; box-shadow: 0 12px 40px rgba(40, 30, 18, .12); }

.reader-foot { display: grid; grid-template-columns: auto 1fr auto; gap: 18px; align-items: center; padding: 20px 0 0; }
.reader-foot button { padding: 9px 13px; border-radius: 3px; }
.reader-foot button:hover, .reader-foot button:focus-visible { border-color: var(--ink); outline: none; }
.reader-foot p { margin: 0; color: var(--muted); text-align: center; font-size: 14px; }

.method { border-top: 1px solid var(--ink); display: grid; grid-template-columns: 180px 1fr; gap: 24px; max-width: 1440px; margin: 0 auto; padding: 24px 32px 42px; color: var(--muted); line-height: 1.7; }
.method strong { color: var(--ink); }

@media (max-width: 760px) {
  .masthead { align-items: start; padding: 28px 18px 20px; }
  .progress { display: none; }
  main { padding: 16px 18px 36px; }
  .pages.compare { grid-template-columns: 1fr; }
  .reader-head { padding-top: 18px; }
  .reader-foot { grid-template-columns: auto auto; }
  .reader-foot p { grid-column: 1 / -1; grid-row: 1; text-align: left; }
  .method { margin: 0 18px; padding: 20px 0 32px; grid-template-columns: 1fr; gap: 6px; }
}

@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }