:root {
  color-scheme: light dark;
  --bg: #f4f4f5;
  --panel: #ffffff;
  --ink: #18181b;
  --muted: #6b7280;
  --line: #d4d4d8;
  --accent: #2563eb;
  --accent-ink: #ffffff;
  --warn: #b45309;
  --err: #b91c1c;
  --radius: 10px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #18181b; --panel: #232327; --ink: #f4f4f5; --muted: #a1a1aa;
    --line: #3f3f46; --accent: #60a5fa; --accent-ink: #0b1220;
    --warn: #fbbf24; --err: #f87171;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font: 15px/1.55 system-ui, -apple-system, "Segoe UI", sans-serif;
}
code { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: .92em; }

.top { padding: 1.6rem 1.25rem .9rem; max-width: 1180px; margin: 0 auto; }
.top h1 { margin: 0 0 .3rem; font-size: 1.4rem; letter-spacing: -.01em; }
.sub { margin: 0; color: var(--muted); max-width: 70ch; }
main { max-width: 1180px; margin: 0 auto; padding: 0 1.25rem 2rem; }

.drop {
  border: 2px dashed var(--line); border-radius: var(--radius);
  padding: 2.75rem 1.5rem; text-align: center; background: var(--panel);
  transition: border-color .15s, background .15s;
}
.drop.over { border-color: var(--accent); background: color-mix(in srgb, var(--accent) 7%, var(--panel)); }
.dropline { margin: 0 0 .9rem; font-size: 1.05rem; }
.hint { color: var(--muted); font-size: .88rem; margin: .8rem 0 0; }

/* Once files are loaded the drop target becomes a slim bar, so the results
   and preview are visible without scrolling past it. */
.drop.compact {
  display: flex; align-items: center; justify-content: center; gap: .75rem;
  padding: .6rem .9rem; margin-bottom: 1.1rem; text-align: left;
}
.drop.compact .dropline { margin: 0; font-size: .9rem; color: var(--muted); }
.drop.compact .hint { display: none; }
.drop.compact button { padding: .35rem .75rem; font-size: .88rem; }

button {
  font: inherit; border-radius: 7px; padding: .5rem .95rem;
  cursor: pointer; border: 1px solid var(--line); background: var(--panel);
  color: var(--ink);
}
button:hover { border-color: var(--accent); }
button:disabled { opacity: .45; cursor: not-allowed; border-color: var(--line); }
.primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
.primary:hover { filter: brightness(1.08); }
.ghost { background: transparent; }

.cols { display: grid; grid-template-columns: 290px 1fr; gap: 1.1rem; align-items: start; }

.panel {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1rem; position: sticky; top: 1rem;
}
.panel > summary {
  font-size: .95rem; text-transform: uppercase; letter-spacing: .06em;
  color: var(--muted); font-weight: 600; cursor: pointer; list-style: none;
  display: flex; align-items: center; justify-content: space-between;
}
.panel > summary::-webkit-details-marker { display: none; }
.panel > summary::after {
  content: "▾"; transition: transform .15s; font-size: .9rem;
}
.panel[open] > summary { margin-bottom: .85rem; }
.panel[open] > summary::after { transform: rotate(180deg); }
.panel > summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
.field { display: block; margin-bottom: 1rem; }
.field > span:first-child, legend { display: block; font-weight: 600; margin-bottom: .3rem; font-size: .9rem; }
.field small { display: block; color: var(--muted); font-size: .8rem; margin-top: .25rem; }
.field select, .field input[type=number] {
  width: 100%; font: inherit; padding: .4rem .5rem; border-radius: 6px;
  border: 1px solid var(--line); background: var(--bg); color: var(--ink);
}
.field.check { display: grid; grid-template-columns: auto 1fr; gap: .2rem .45rem; }
.field.check input { margin: .25rem 0 0; }
.field.check > span { font-weight: 600; font-size: .9rem; margin: 0; }
.field.check small { grid-column: 2; margin-top: .1rem; }
.row { display: flex; gap: .5rem; align-items: center; }
.row input[type=range] { flex: 1; }
output { font-variant-numeric: tabular-nums; font-size: .86rem; min-width: 5.5em; text-align: right; }
fieldset.field { border: 1px solid var(--line); border-radius: 8px; padding: .7rem; }
.pieces { max-height: 230px; overflow: auto; margin-top: .5rem; font-size: .85rem; }
.pieces label { display: flex; gap: .4rem; align-items: center; padding: .12rem 0; }

.files { display: grid; gap: .7rem; }
.card {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: .85rem 1rem;
}
.card.active { border-color: var(--accent); }
.card h3 { margin: 0 0 .3rem; font-size: 1rem; word-break: break-word; }
.meta { color: var(--muted); font-size: .86rem; }
.tags { display: flex; flex-wrap: wrap; gap: .35rem; margin: .5rem 0 .6rem; }
.tag {
  font-size: .76rem; padding: .12rem .45rem; border-radius: 999px;
  border: 1px solid var(--line); display: inline-flex; gap: .3rem; align-items: center;
}
.dot { width: 8px; height: 8px; border-radius: 50%; display: inline-block; }
.cardacts { display: flex; gap: .45rem; flex-wrap: wrap; }
.cardacts button { padding: .34rem .7rem; font-size: .87rem; }
.note { color: var(--warn); font-size: .84rem; margin: .45rem 0 0; }
.bad { color: var(--err); }

.actions { display: flex; gap: .5rem; flex-wrap: wrap; margin: 1.1rem 0; }

.preview { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); }
.legend {
  display: flex; flex-wrap: wrap; gap: .5rem 1rem; padding: .7rem 1rem;
  border-bottom: 1px solid var(--line); font-size: .85rem;
}
.legend label { display: inline-flex; gap: .35rem; align-items: center; cursor: pointer; }
.sw { width: 11px; height: 11px; border-radius: 2px; display: inline-block; }
.stage { padding: 1rem; }
.stage svg { width: 100%; height: auto; background: #fff; display: block; border-radius: 6px; }
/* Screen-constant strokes: widths are in px, so lines stay crisp whether the
   marker is 200 mm or 3.2 m across. */
.stage svg [data-kind] { vector-effect: non-scaling-stroke; }
.pagebox {
  fill: none; stroke: #94a3b8; stroke-width: 1.5; stroke-dasharray: 9 7;
  vector-effect: non-scaling-stroke;
}

/* Single column below this width. The options move to a collapsed accordion
   above the results rather than a 1000px-tall block the user has to scroll
   past to reach their converted file. Sticky is dropped: a panel taller than
   the viewport cannot usefully stick. */
@media (max-width: 860px) {
  .cols { grid-template-columns: 1fr; gap: .8rem; }
  .panel { position: static; padding: .75rem .9rem; }
  .pieces { max-height: 40vh; }
  .top { padding: 1.1rem 1rem .6rem; }
  .top h1 { font-size: 1.2rem; }
  main { padding: 0 1rem 2rem; }
  .drop { padding: 1.75rem 1rem; }
  .actions { gap: .4rem; }
  .actions button { flex: 1 1 auto; }
  .legend { gap: .45rem .8rem; padding: .6rem .75rem; }
  .stage { padding: .6rem; }
}

@media (max-width: 420px) {
  .cardacts button, .actions button { width: 100%; }
  .tag { font-size: .72rem; }
  /* Stack the compact drop bar rather than letting the label and the button
     each wrap to two lines beside one another. */
  .drop.compact { flex-direction: column; gap: .5rem; text-align: center; }
  .drop.compact button { width: 100%; }
  .top h1 { font-size: 1.1rem; }
}
.drop.compact button { white-space: nowrap; }

.errors {
  margin-top: 1rem; border: 1px solid var(--err); border-radius: var(--radius);
  padding: .85rem 1rem; background: color-mix(in srgb, var(--err) 8%, var(--panel));
}
.errors p { margin: .2rem 0; }
.foot { max-width: 1180px; margin: 0 auto; padding: 0 1.25rem 2.5rem; color: var(--muted); font-size: .85rem; }
.spin { display: inline-block; width: .8em; height: .8em; border: 2px solid var(--muted);
        border-top-color: transparent; border-radius: 50%; animation: s .7s linear infinite; }
@keyframes s { to { transform: rotate(360deg); } }