/* A paper puzzle book: warm paper, faint graph lines, ink fills, one vermilion accent.
   No web fonts (the content security policy allows only this site), so the type uses
   good system faces: a book serif for headings, a monospace for every number. */

:root {
  --paper: #f3efe6;
  --paper-deep: #e9e3d6;
  --card: #fbf9f4;
  --ink: #1e2433;
  --ink-soft: #4b5163;
  --ink-faint: #8b8d93;
  --rule: #d8d1c2;
  --rule-strong: #2b3142;
  --accent: #c8553d;
  --accent-deep: #a8432e;
  --done: #2f6b4f;
  --cell: 24px;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --sans: "Segoe UI", system-ui, -apple-system, Roboto, sans-serif;
  --mono: "Cascadia Mono", "SF Mono", Consolas, "Liberation Mono", ui-monospace, monospace;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { background: var(--paper); }
body {
  margin: 0; min-height: 100vh; color: var(--ink); font-family: var(--sans); font-size: 15px;
  background-color: var(--paper);
  background-image:
    linear-gradient(rgba(43, 49, 66, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(43, 49, 66, 0.045) 1px, transparent 1px);
  background-size: 22px 22px;
}
button { font: inherit; color: inherit; cursor: pointer; }
h1, h2 { font-family: var(--serif); font-weight: 600; letter-spacing: -0.01em; }

/* ------------------------------------------------------------------ masthead -- */
.masthead {
  display: flex; align-items: center; gap: 14px; padding: 14px 28px;
  border-bottom: 2px solid var(--ink); background: var(--paper);
  position: sticky; top: 0; z-index: 5;
}
.wordmark { display: flex; align-items: center; gap: 10px; }
.logo { display: grid; grid-template-columns: repeat(3, 7px); gap: 2px; }
.logo i { width: 7px; height: 7px; border: 1px solid var(--ink); }
.logo i.on { background: var(--ink); }
.logo i:nth-child(5) { background: var(--accent); border-color: var(--accent); }
.wordmark-text { font-family: var(--serif); font-size: 21px; font-weight: 600; }
.spacer { flex: 1; }
.who {
  font-family: var(--mono); font-size: 13px; padding: 3px 9px; border: 1px solid var(--rule);
  border-radius: 999px; color: var(--ink-soft); background: var(--card);
}
.help-button {
  width: 30px; height: 30px; border-radius: 50%; border: 2px solid var(--ink); background: var(--card);
  font-family: var(--serif); font-weight: 700; font-size: 16px; line-height: 1;
}
.help-button:hover { background: var(--ink); color: var(--card); }
.text-button { background: none; border: none; padding: 4px 2px; color: var(--ink-soft); text-decoration: underline; text-underline-offset: 3px; }
.text-button:hover { color: var(--accent); }

/* -------------------------------------------------------------------- shared -- */
main { padding: 28px 28px 56px; max-width: 1180px; margin: 0 auto; }
.primary {
  background: var(--ink); color: var(--card); border: none; border-radius: 3px;
  padding: 10px 20px; font-weight: 600; letter-spacing: 0.01em;
  box-shadow: 3px 3px 0 var(--accent);
}
.primary:hover:not(:disabled) { background: var(--accent-deep); }
.primary:disabled { opacity: 0.45; cursor: default; box-shadow: none; }
.paper {
  background: var(--card); border: 1px solid var(--rule); border-radius: 2px;
  box-shadow: 0 1px 0 var(--rule), 6px 6px 0 rgba(30, 36, 51, 0.06);
}
.kicker {
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--accent);
}

/* --------------------------------------------------------------------- login -- */
.login { max-width: 420px; margin: 7vh auto 0; padding: 34px 34px 30px; }
.login h1 { font-size: 30px; margin: 6px 0 4px; }
.login .tagline { color: var(--ink-soft); margin: 0 0 26px; font-family: var(--serif); font-style: italic; }
.field { display: flex; flex-direction: column; gap: 5px; margin-bottom: 18px; }
.field label { font-size: 13px; color: var(--ink-soft); }
.field input {
  font: 16px var(--mono); padding: 8px 2px; border: none; border-bottom: 2px solid var(--rule);
  background: transparent; color: var(--ink); outline: none; letter-spacing: 0.04em;
}
.field input:focus { border-bottom-color: var(--ink); }
.error { color: var(--accent-deep); min-height: 1.4em; margin: 0 0 12px; font-size: 14px; }

/* ------------------------------------------------------------------- consent -- */
.consent { max-width: 640px; margin: 4vh auto 0; padding: 34px; }
.consent h1 { margin: 6px 0 16px; font-size: 28px; }
.consent p { line-height: 1.6; color: var(--ink-soft); }
.consent label {
  display: flex; gap: 12px; align-items: flex-start; margin: 22px 0; padding-top: 18px;
  border-top: 1px dashed var(--rule); line-height: 1.5;
}
.consent input { width: 18px; height: 18px; margin-top: 2px; accent-color: var(--ink); }

/* ---------------------------------------------------------------- puzzle list -- */
.list-head { display: flex; align-items: baseline; gap: 18px; flex-wrap: wrap; margin-bottom: 6px; }
.list-head h1 { font-size: 34px; margin: 0; }
.tally { font-family: var(--mono); font-size: 13px; color: var(--ink-soft); }
.intro { color: var(--ink-soft); max-width: 640px; line-height: 1.55; margin: 6px 0 26px; }
.shelf {
  display: grid; grid-template-columns: 110px 1fr; gap: 18px; align-items: center;
  padding: 16px 0; border-top: 1px solid var(--rule);
}
.shelf-label { font-family: var(--serif); font-size: 26px; font-weight: 600; white-space: nowrap; }
.shelf-label small { display: block; font-family: var(--mono); font-size: 11px; font-weight: 400; color: var(--ink-faint); letter-spacing: 0.08em; }
.shelf-items { display: flex; gap: 14px; flex-wrap: wrap; }
.tile {
  width: 132px; padding: 10px; border: 1px solid var(--rule); background: var(--card);
  display: flex; flex-direction: column; gap: 8px; text-align: left; border-radius: 2px;
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}
.tile:hover { transform: translate(-2px, -2px); box-shadow: 4px 4px 0 var(--ink); }
.tile:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.thumb {
  position: relative; width: 100%; aspect-ratio: 1; border: 2px solid var(--ink);
  background-color: var(--card);
  background-image:
    linear-gradient(var(--rule) 1px, transparent 1px),
    linear-gradient(90deg, var(--rule) 1px, transparent 1px);
  background-size: calc(100% / var(--blocks)) calc(100% / var(--blocks));
}
.tile.solved .thumb { background-color: var(--ink); background-image:
    linear-gradient(rgba(251, 249, 244, 0.18) 1px, transparent 1px),
    linear-gradient(90deg, rgba(251, 249, 244, 0.18) 1px, transparent 1px); }
.tile.open .thumb::after {
  content: ""; position: absolute; left: 0; bottom: 0; width: 100%; height: 38%;
  background: repeating-linear-gradient(135deg, var(--accent) 0 3px, transparent 3px 7px); opacity: 0.55;
}
.tile.solved .thumb::after {
  content: "✓"; position: absolute; inset: 0; display: grid; place-items: center;
  color: var(--card); font-size: 34px; font-family: var(--serif);
}
.tile-name { font-family: var(--serif); font-size: 16px; font-weight: 600; }
.tile-status { font-size: 12px; color: var(--ink-soft); font-family: var(--mono); }
.tile.solved .tile-status { color: var(--done); }
.tile.open .tile-status { color: var(--accent-deep); }

/* ------------------------------------------------------------------- solving -- */
.solve-head {
  display: flex; align-items: center; gap: 18px; flex-wrap: wrap; margin: 0 auto 18px;
  max-width: max-content;
}
.back { background: none; border: none; padding: 0; color: var(--ink-soft); font-size: 14px; }
.back:hover { color: var(--accent); }
.solve-title { font-family: var(--serif); font-size: 22px; font-weight: 600; margin: 0; }
.solve-number { font-family: var(--serif); font-size: 22px; color: var(--ink-faint); }
.tools { display: inline-flex; border: 2px solid var(--ink); border-radius: 3px; overflow: hidden; }
.tools button {
  border: none; background: var(--card); padding: 6px 12px; display: flex; align-items: center; gap: 7px;
  font-size: 14px;
}
.tools button + button { border-left: 2px solid var(--ink); }
.tools button.active { background: var(--ink); color: var(--card); }
.swatch { width: 12px; height: 12px; display: inline-block; }
.swatch.fill { background: currentColor; }
.swatch.mark { position: relative; }
.swatch.mark::before, .swatch.mark::after {
  content: ""; position: absolute; left: -1px; right: -1px; top: 5px; height: 2px; background: currentColor;
}
.swatch.mark::before { transform: rotate(45deg); }
.swatch.mark::after { transform: rotate(-45deg); }
.clock {
  font-family: var(--mono); font-size: 18px; font-variant-numeric: tabular-nums; letter-spacing: 0.04em;
  padding: 3px 10px; border: 1px solid var(--rule); background: var(--card); border-radius: 2px;
}
.save-state { font-size: 12px; font-family: var(--mono); color: var(--ink-faint); min-width: 5em; }
.save-state.bad { color: var(--accent-deep); font-family: var(--sans); max-width: 260px; }

.board {
  display: grid; grid-template-columns: auto auto; grid-template-rows: auto auto;
  width: max-content; margin: 0 auto; user-select: none; -webkit-user-select: none;
  padding: 14px 18px 18px 14px;
}
.colclues, .grid { display: grid; grid-template-columns: repeat(var(--w), var(--cell)); }
.rowclues, .grid { grid-template-rows: repeat(var(--h), var(--cell)); }
.rowclues { display: grid; }
/* clue type never drops below 12px, however small the cells get on a 30x30 board */
.colclue, .rowclue { font-family: var(--mono); font-size: max(12px, calc(var(--cell) * 0.5)); color: var(--ink); font-variant-numeric: tabular-nums; }
.colclue {
  display: flex; flex-direction: column; justify-content: flex-end; align-items: center;
  line-height: 1.2; padding-bottom: 5px;
}
.rowclue {
  display: flex; justify-content: flex-end; align-items: center; gap: calc(var(--cell) * 0.32);
  padding-right: 8px;
}
.grid { border: 2px solid var(--rule-strong); touch-action: none; cursor: crosshair; background: var(--card); }
.cell {
  width: var(--cell); height: var(--cell); border-right: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule); position: relative;
}
.cell.r5 { border-right: 2px solid var(--rule-strong); }
.cell.b5 { border-bottom: 2px solid var(--rule-strong); }
.cell.last-col { border-right: none; }
.cell.last-row { border-bottom: none; }
.cell.filled { background: var(--ink); }
.cell.marked::before, .cell.marked::after {
  content: ""; position: absolute; left: 24%; right: 24%; top: calc(50% - 1px); height: 2px;
  background: var(--ink-faint); border-radius: 1px;
}
.cell.marked::before { transform: rotate(45deg); }
.cell.marked::after { transform: rotate(-45deg); }
.grid.locked { cursor: default; }

/* ------------------------------------------------------------------- dialogs -- */
.overlay {
  position: fixed; inset: 0; background: rgba(30, 36, 51, 0.42);
  display: flex; align-items: center; justify-content: center; padding: 18px; z-index: 10;
}
.sheet {
  background: var(--card); border: 2px solid var(--ink); border-radius: 2px; padding: 26px 28px;
  max-width: 620px; max-height: 90vh; overflow-y: auto; box-shadow: 8px 8px 0 var(--accent);
}
.sheet h2 { margin: 0 0 12px; font-size: 24px; }
.sheet p { line-height: 1.55; color: var(--ink-soft); }
.sheet-actions { display: flex; justify-content: flex-end; margin-top: 18px; }
.controls { display: grid; grid-template-columns: max-content 1fr; align-items: center; gap: 8px 14px; margin: 14px 0; }
.controls dt { font-family: var(--mono); font-size: 13px; color: var(--ink); }
.controls dd { margin: 0; color: var(--ink-soft); line-height: 1.45; }
.example { display: flex; align-items: center; gap: 12px; margin: 10px 0 16px; }
.example .rowclue { --cell: 26px; padding: 0; }
.example .cells { display: flex; border: 2px solid var(--rule-strong); }
.example .cell { --cell: 26px; }
.solved-sheet { text-align: center; min-width: 300px; }
.solved-sheet .sheet-actions { justify-content: center; }
.stamp {
  width: 64px; height: 64px; margin: 0 auto 10px; border: 3px solid var(--done); border-radius: 50%;
  display: grid; place-items: center; color: var(--done); font-size: 32px; font-family: var(--serif);
  transform: rotate(-8deg);
}
.solved-time { font-family: var(--mono); font-size: 20px; color: var(--ink) !important; }

@media (max-width: 640px) {
  .masthead { padding: 12px 16px; }
  main { padding: 20px 16px 40px; }
  .shelf { grid-template-columns: 1fr; gap: 10px; }
  .tile { width: calc(50% - 7px); }
}