:root {
  --bg1: #1a1626;
  --bg2: #3b2a63;
  --ink: #e2e8f0;
  --dim: #94a3b8;
  --line: rgba(255, 255, 255, .16);
  --accent: #a78bfa;
  --good: #22c55e;
  --pill: rgba(255, 255, 255, .12);
  --card: #ffffff;
  --cardInk: #251a3d;
}
* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
/* R-C15: the page itself never scrolls, and nothing chains out of it. */
html, body {
  margin: 0; padding: 0; height: 100%;
  overflow: hidden; overscroll-behavior: none;
}
body {
  height: 100vh; height: 100dvh;
  display: flex; flex-direction: column;
  font-family: ui-rounded, "SF Pro Rounded", "Segoe UI", system-ui, sans-serif;
  background: radial-gradient(120% 120% at 50% 0%, var(--bg2), var(--bg1));
  color: var(--ink);
  user-select: none; -webkit-user-select: none; -webkit-touch-callout: none;
  touch-action: manipulation;
}

#hdr {
  display: flex; align-items: center; gap: 8px;
  padding: 10px 14px 6px;
  padding-top: calc(10px + env(safe-area-inset-top));
  padding-left: calc(14px + env(safe-area-inset-left));
  padding-right: calc(14px + env(safe-area-inset-right));
}
.pill {
  background: var(--pill); border-radius: 999px; padding: 7px 12px;
  font-size: 15px; font-weight: 700; white-space: nowrap;
  overflow: hidden; text-overflow: ellipsis;
}
/* R-C19: a number the player WATCHES CHANGE gets tabular figures. Measured on
   word-search: the clock pill swings between 51.3px and 66.3px as it counts,
   and the pill beside it slides 8px sideways — every second, and again at
   0:09 -> 0:10. Crossword found this, fixed its own clock, and wrote the
   reason into its own stylesheet, where the other four games could not read
   it. Fourth time a lesson has been recorded only where it was learned. */
#runInfo { flex: 1 1 auto; min-width: 0; display: flex; align-items: center; gap: 8px;
           overflow: hidden; font-variant-numeric: tabular-nums; }
#hudTheme { flex: 0 1 auto; min-width: 0; }
.iconBtn {
  background: var(--pill); border: none; color: #fff; border-radius: 999px;
  flex: 0 0 auto; width: 46px; height: 46px; font-size: 20px; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: transform .08s;
}
.iconBtn:active { transform: scale(.9); }
.iconBtn[hidden] { display: none; }
/* ---- the hint control (docs/offline-pwa.md R-C16) -------------------------
   ONE bulb, and the count as an OVERLAID badge. Absolutely positioned inside
   `.bulb`, so 10 -> 9 -> 8 can never change the button's width and shove
   whatever sits beside it — which is exactly what the inline count did on a
   phone. The number is always how many are LEFT, it is shown at 1 and at 0,
   and at 0 the button is disabled with the badge still on it, because a
   control that vanishes teaches a child nothing about why.
   The badge is dark with a pale ring at every game, on purpose: the games run
   from near-black to amber to a light theme, and a dark pill with a light halo
   is the one combination that reads on all of them. */
.hintBtn { position: relative; overflow: visible; }
.hintBtn .bulb { position: relative; display: inline-block; line-height: 1; }
.hintBtn .hintN {
  position: absolute; right: -9px; bottom: -6px;
  min-width: 16px; height: 16px; padding: 0 3px; border-radius: 999px;
  background: #0f172a; color: #f8fafc; box-shadow: 0 0 0 1.5px rgba(255, 255, 255, .6);
  font: 800 10px/16px inherit; letter-spacing: 0; pointer-events: none;
}
.hintBtn:disabled .hintN, .hintBtn[disabled] .hintN { background: #64748b; }
/* `wide` = the bulb is followed by a WORD. The badge hangs 9px past the
   bulb, so without this it sits on the first letter of the label. */
.hintBtn.wide .bulb { margin-right: 11px; }

/* Same call snake makes: below 480px the pills take a row of their own rather
   than being sliced by overflow:hidden, because four 46px targets and three
   pills do not both fit and a button may never give way. */
@media (max-width: 480px) {
  #hdr { flex-wrap: wrap; row-gap: 6px; }
  #runInfo { order: 2; flex: 1 1 100%; justify-content: center; overflow: visible; }
  #hdrHelp { margin-left: 0; }
  #hdrHome { margin-right: auto; }
}

/* R-C12: header and footer are pinned, so the frame between them names its
   scroll region — and it is the WORD LIST, never the page. */
#stage {
  position: relative; flex: 1; min-height: 0;
  display: flex; flex-direction: column; align-items: center;
  padding: 0 8px env(safe-area-inset-bottom);
  gap: 6px;
}
/* See word-search's copy of this comment: without `width: 100%` this box
   shrink-wraps the canvas whose size is computed from it, and the grid freezes
   at whatever the first pass produced. Measured at 297px inside a 359px stage
   — 62px thrown away. */
#board {
  flex: 1 1 auto; min-height: 0; width: 100%;
  display: flex; align-items: center; justify-content: center;
}
#cv { touch-action: none; border-radius: 14px; box-shadow: 0 10px 40px rgba(0, 0, 0, .45); }

/* R6b: the list is the other half of the puzzle, so it is always on screen.
   Capped at a third of the stage and scrollable inside itself, contained so a
   flick through a long list cannot drag the frame. */
#wordList {
  flex: 0 0 auto; width: 100%; max-height: 28%;
  overflow-y: auto; overscroll-behavior: contain;
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 5px 7px; padding: 2px 2px 6px;
}
.wsw {
  font-size: 14px; font-weight: 800; letter-spacing: .4px;
  padding: 5px 10px; border-radius: 999px;
  background: rgba(255, 255, 255, .09); color: var(--ink);
  border: 1px solid var(--line);
}
.wsw.got {
  text-decoration: line-through;
  text-decoration-thickness: 2px;
  opacity: .55;
  border-color: transparent;
}

.overlay {
  position: absolute; inset: 0;
  display: flex; align-items: flex-start; justify-content: center;
  overflow-y: auto; -webkit-overflow-scrolling: touch; overscroll-behavior: contain;
  background: rgba(20, 14, 34, .62);
  backdrop-filter: blur(5px); -webkit-backdrop-filter: blur(5px);
  z-index: 5; padding: 16px;
}
.overlay.hidden { display: none; }
.card {
  background: var(--card); color: var(--cardInk); border-radius: 24px;
  padding: 24px 22px 20px; width: min(360px, 94%);
  margin: auto; flex: 0 0 auto; text-align: center;
  box-shadow: 0 16px 50px rgba(0, 0, 0, .45);
  animation: pop .25s ease-out;
}
@keyframes pop { from { transform: scale(.85); opacity: 0; } to { transform: scale(1); opacity: 1; } }
@media (prefers-reduced-motion: reduce) { .card { animation: none; } }
.card .big { font-size: 52px; line-height: 1; }
.card h1 { margin: 6px 0 4px; font-size: 28px; font-weight: 800; }
.card .hint { margin: 4px 0 14px; font-size: 14px; color: #6b5b86; font-weight: 600; }
.card .lbl { margin: 14px 0 6px; font-size: 13px; color: #6b5b86; font-weight: 700; text-align: left; }
.blurb { margin: 6px 0 4px; font-size: 13px; line-height: 1.4; color: #6b5b86; font-weight: 600; min-height: 1em; }
.howBody { text-align: left; font-size: 15px; line-height: 1.5; }
.howBody p { margin: 0 0 9px; }

.seg { display: flex; gap: 6px; }
.seg.wrap { flex-wrap: wrap; }
.opt {
  flex: 1 1 auto; min-width: 0; min-height: 44px; padding: 8px 8px;
  border-radius: 12px; border: 2px solid #ded6ec; background: #f6f3fb;
  color: var(--cardInk); font: 800 14px/1.2 inherit; font-family: inherit;
  cursor: pointer; transition: transform .08s;
}
.opt:active { transform: scale(.96); }
.opt[aria-checked="true"] { border-color: var(--good); background: #e6f8ec; }

.btn {
  display: block; width: 100%; border: none; border-radius: 16px; padding: 14px;
  margin-top: 10px; font: 800 18px/1 inherit; font-family: inherit;
  cursor: pointer; background: #f0ecf7; color: var(--cardInk);
  transition: transform .08s;
}
.btn:active { transform: scale(.96); }
.btn.primary {
  background: linear-gradient(180deg, #a78bfa, #8b5cf6); color: #fff;
  box-shadow: 0 5px 0 #6d28d9;
}
.btn.primary:active { box-shadow: 0 2px 0 #6d28d9; transform: translateY(3px) scale(.98); }
.stats { display: flex; justify-content: center; flex-wrap: wrap; gap: 8px 18px; font-size: 19px; margin: 8px 0 12px; }

#toast {
  position: fixed; left: 50%; transform: translateX(-50%);
  bottom: calc(58px + env(safe-area-inset-bottom));
  background: rgba(20, 14, 34, .92); color: #fff;
  padding: 9px 15px; border-radius: 999px; font-size: 14px; font-weight: 700;
  opacity: 0; pointer-events: none; transition: opacity .18s; z-index: 8;
  max-width: 88vw; text-align: center;
}
#toast.on { opacity: 1; }
.hidden { display: none !important; }

/* ---- sudoku's own ------------------------------------------------------- */

/* R13: nine 44px keys plus their gaps need 444px, so this is a PAD that wraps
   rather than a row. Six per row is the widest that fits a 320px phone, and
   V7 reports the resulting key size per size against the floor. */
#pad {
  flex: 0 0 auto; width: 100%; max-width: 420px;
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 6px; padding: 2px 4px 6px;
}
.key {
  flex: 0 0 auto; min-width: 44px; min-height: 44px;
  padding: 0 6px; border-radius: 12px;
  border: 1px solid var(--line); background: rgba(255, 255, 255, .10);
  color: var(--ink); font: 800 20px/1 inherit; font-family: inherit;
  cursor: pointer; transition: transform .07s;
}
.key:active { transform: scale(.93); }
/* R-C20: a take-back with nothing to take back greys out where it is. */
.key:disabled { opacity: .38; }
.key:disabled:active { transform: none; }
/* The count of how many of this symbol are still to place. Not decoration:
   scanning for "which symbol is nearly done" is one of the two things a
   solver's eye actually does. */
.key .left {
  display: block; font-size: 10px; font-weight: 700; opacity: .55; margin-top: 1px;
}
.key.done { opacity: .35; }
.key.sel { border-color: var(--accent); background: rgba(167, 139, 250, .28); }
/* The pencil toggle sits in the pad because it changes what the pad DOES. */
#keyNote.on { background: #a78bfa; color: #241b38; border-color: #a78bfa; }
#keyErase { font-size: 17px; }

/* Landscape: the keypad moves BESIDE the grid, for the reason word-search's
   word list does. A square grid is bounded by the smaller dimension, so on a
   wide short window the height is the constraint — and a pad stacked under the
   grid spends the scarce axis on the thing with plenty to spare. */
@media (min-aspect-ratio: 1/1) {
  #stage { flex-direction: row; align-items: stretch; gap: 8px; }
  #board { width: auto; flex: 1 1 auto; min-width: 0; }
  #pad {
    width: auto; flex: 0 0 auto;
    min-width: 106px; max-width: 30%;
    align-content: center;
    padding: 6px 0;
  }
}