/* Puzzle Play — one stylesheet, no framework.
 *
 * Two things here are load-bearing rather than cosmetic:
 *   1. the pointer-events rules, which make a piece grabbable on its painted
 *      shape only, so overlapping pieces in the tray behave like real ones;
 *   2. the .eink block, which flattens colour, kills animation and thickens
 *      outlines for a grayscale, slow-refresh screen.
 */

:root {
  --paper: #fff7e8;
  --ink: #33261a;
  --frame: #ffffff;
  --shadow: rgba(80, 52, 20, 0.22);
  --accent: #f4763b;
  --accent-dark: #d2561e;
  --tray: #ffe6bd;
  --tap: 52px;
}

* { box-sizing: border-box; }

html, body {
  height: 100%;
  margin: 0;
  overflow: hidden;
  background: var(--paper);
  color: var(--ink);
  font-family: "Baloo 2", "Comic Sans MS", "Trebuchet MS", system-ui, -apple-system, sans-serif;
  -webkit-tap-highlight-color: transparent;
  -webkit-text-size-adjust: 100%;
}

body {
  padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
}

/* ---- screens ------------------------------------------------------------ */

.screen { display: none; height: 100%; flex-direction: column; }
#home { display: flex; overflow-y: auto; }
body.playing #home { display: none; }
body.playing #play { display: flex; }

/* ---- buttons ------------------------------------------------------------ */

button {
  font: inherit;
  color: inherit;
  cursor: pointer;
  border: 0;
  background: none;
  touch-action: manipulation;
}

.icon-btn {
  min-width: var(--tap);
  min-height: var(--tap);
  display: grid;
  place-items: center;
  font-size: 1.5rem;
  line-height: 1;
  border-radius: 16px;
  background: #fff;
  box-shadow: 0 2px 0 var(--shadow);
}
.icon-btn:active { transform: translateY(2px); box-shadow: none; }
.icon-btn.on { background: #ffe0b2; outline: 3px solid var(--accent); }
.eink-only { display: none; }

.big-btn {
  min-height: 56px;
  padding: 0 20px;
  font-size: 1.15rem;
  font-weight: 700;
  border-radius: 18px;
  background: #fff;
  box-shadow: 0 3px 0 var(--shadow);
}
.big-btn.primary { background: var(--accent); color: #fff; box-shadow: 0 3px 0 var(--accent-dark); }
.big-btn:active { transform: translateY(3px); box-shadow: none; }

/* ---- home -------------------------------------------------------------- */

/* #home is a flex column and .picker is flex:1 with the default min-height:auto,
 * so once the grid is 100 cards tall it refuses to shrink and squeezes every
 * shrinkable sibling to nothing. Everything around the grid opts out. */
.home-bar, .hint-text, .levels, .cats, .home-foot { flex: 0 0 auto; }

.home-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px 4px;
}
.home-bar h1 { margin: 0; font-size: clamp(1.4rem, 5vw, 2rem); }
.home-tools { margin-left: auto; display: flex; gap: 8px; }
.hint-text { margin: 4px 16px 12px; opacity: 0.75; }

.levels {
  display: flex;
  gap: 10px;
  padding: 0 16px 14px;
  overflow-x: auto;
}
.level {
  flex: 1 0 auto;
  min-width: 96px;
  padding: 10px 14px;
  border-radius: 20px;
  background: #fff;
  box-shadow: 0 3px 0 var(--shadow);
  display: grid;
  justify-items: center;
  gap: 2px;
}
.level[aria-checked="true"] { background: #ffe0b2; outline: 4px solid var(--accent); }
.level-emoji { font-size: 1.7rem; }
.level-pieces { font-size: 1.3rem; font-weight: 800; }
.level-ages { font-size: 0.78rem; opacity: 0.7; }

/* Same shape as .levels: one horizontally scrolling row of big tap targets. */
.cats {
  display: flex;
  gap: 8px;
  padding: 0 16px 14px;
  overflow-x: auto;
}
.cat {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 7px;
  min-height: 46px;
  padding: 8px 16px;
  border-radius: 23px;
  background: #fff;
  font-size: 0.95rem;
  font-weight: 700;
  box-shadow: 0 3px 0 var(--shadow);
}
.cat[aria-checked="true"] { background: #ffe0b2; outline: 4px solid var(--accent); }
.cat:active { transform: translateY(3px); box-shadow: none; }
.cat-emoji { font-size: 1.25rem; line-height: 1; }

.picker {
  flex: 1;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(116px, 1fr));
  gap: 12px;
  padding: 0 16px 16px;
  align-content: start;
}
.card {
  position: relative;
  aspect-ratio: 1;
  border-radius: 24px;
  background: #fff;
  box-shadow: 0 4px 0 var(--shadow);
  display: grid;
  place-content: center;
  gap: 4px;
}
.card:active { transform: translateY(3px); box-shadow: none; }
.card-emoji { font-size: clamp(2.2rem, 9vw, 3.2rem); }
.card-name { font-size: 0.9rem; font-weight: 700; }
.card-stars { position: absolute; top: 8px; right: 10px; color: #f9a825; font-size: 0.85rem; }

.home-foot { padding: 0 16px 18px; font-size: 0.8rem; opacity: 0.55; }

/* ---- play bar ---------------------------------------------------------- */

.play-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
}
.play-bar h2 { margin: 0; font-size: 1.05rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.count {
  font-weight: 800;
  font-size: 1rem;
  padding: 4px 10px;
  border-radius: 12px;
  background: #fff;
  box-shadow: 0 2px 0 var(--shadow);
}
.spacer { flex: 1; }

/* ---- stage: board + tray + pieces -------------------------------------- */

#stage {
  position: relative;
  flex: 1;
  min-height: 0;
  /* Without this, a touch-drag scrolls the page instead of moving a piece. */
  touch-action: none;
  user-select: none;
  -webkit-user-select: none;
}

#board, #tray, #layer { position: absolute; }

#board {
  background: var(--frame);
  border-radius: 10px;
  box-shadow: 0 0 0 5px #fff, 0 4px 14px var(--shadow);
  overflow: hidden;
}

#guide, #guide svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.guide-picture { opacity: 0; transition: opacity 0.2s; }
#board.hint .guide-picture { opacity: 0.2; }
.guide-lines path {
  fill: none;
  stroke: rgba(70, 50, 30, 0.22);
  stroke-width: 1.6;
  stroke-dasharray: 7 7;
}
#board.solved .guide-lines { display: none; }
/* Clipped SVG edges leave hairline seams between neighbouring pieces. Once the
   picture is complete, the full-strength guide underneath fills them in, so the
   finished picture reads as one clean image. */
#board.solved .guide-picture { opacity: 1; }
#board.solved { box-shadow: 0 0 0 5px #fff, 0 0 0 10px var(--accent), 0 4px 18px var(--shadow); }

#tray {
  background: var(--tray);
  border: 3px dashed rgba(120, 80, 40, 0.28);
  border-radius: 22px;
}

#layer { inset: 0; pointer-events: none; }

.piece {
  position: absolute;
  top: 0;
  left: 0;
  will-change: transform;
  pointer-events: none;
}
.piece-art {
  width: 100%;
  height: 100%;
  overflow: visible;
  pointer-events: none;
  /* The tight first shadow acts as a thin dark outline, so a piece still reads
     as a separate object when its picture happens to match the tray colour. */
  filter: drop-shadow(0 0 1px rgba(60, 40, 20, 0.55)) drop-shadow(0 2px 2px rgba(60, 40, 20, 0.4));
  transition: transform 0.08s;
}
/* The clipped artwork is the only hit target, so a piece is grabbable exactly
   where it is drawn — including the knobs, and not in the empty corners. */
.piece-art > g { pointer-events: auto; }
.piece-edge { fill: none; stroke: rgba(255, 255, 255, 0.8); stroke-width: 2; }

.piece:focus-visible { outline: none; }
.piece:focus-visible .piece-art { filter: drop-shadow(0 0 0 #fff) drop-shadow(0 0 6px var(--accent)); }

.piece.dragging .piece-art {
  transform: scale(1.06);
  filter: drop-shadow(0 0 1px rgba(60, 40, 20, 0.55)) drop-shadow(0 6px 8px rgba(60, 40, 20, 0.5));
}
.piece.placed .piece-art { filter: none; }
.piece.placed .piece-edge { stroke: transparent; }
.piece.placed .piece-art > g { pointer-events: none; }

/* ---- celebration ------------------------------------------------------- */

#win {
  position: absolute;
  inset: 0;
  overflow: hidden;
  z-index: 50;
  /* No scrim: only the card itself is interactive, the picture stays clear. */
  pointer-events: none;
}
#win[hidden] { display: none; }
.win-card {
  position: absolute;
  transform: translate(-50%, -50%);
  display: grid;
  align-content: center;
  justify-items: center;
  gap: 14px;
  padding: 16px;
  text-align: center;
  pointer-events: auto;
  background: rgba(255, 255, 255, 0.94);
  border-radius: 22px;
  box-shadow: 0 6px 18px var(--shadow);
}
.win-title { margin: 0; font-size: clamp(1.4rem, 5vw, 2.2rem); font-weight: 800; }
.win-buttons { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }

.confetti {
  position: absolute;
  top: -20px;
  width: 10px;
  height: 16px;
  border-radius: 2px;
  animation: fall 2.2s linear forwards;
}
@keyframes fall {
  to { transform: translateY(105vh) rotate(540deg); }
}

/* ---- E Ink ------------------------------------------------------------- */

body.eink {
  --paper: #ffffff;
  --tray: #ffffff;
  --shadow: rgba(0, 0, 0, 0.55);
  --accent: #000000;
  --accent-dark: #000000;
}
/* Colour is noise on a grayscale panel; contrast is what is left to spend. */
body.eink #stage, body.eink .picker, body.eink .win-art { filter: grayscale(1) contrast(1.35); }
body.eink .icon-btn, body.eink .big-btn, body.eink .card, body.eink .level, body.eink .cat { border: 2px solid #000; box-shadow: none; }
body.eink .big-btn.primary { background: #000; color: #fff; }
body.eink #board { box-shadow: none; border: 3px solid #000; }
body.eink #tray { border: 3px dashed #000; }
body.eink .piece-art { filter: none; }
body.eink .piece-edge { stroke: #000; stroke-width: 2.6; }
body.eink .piece.placed .piece-edge { stroke: rgba(0, 0, 0, 0.35); }
body.eink .guide-lines path { stroke: #000; stroke-width: 1.4; }
body.eink .eink-only { display: grid; }
/* Animation smears on E Ink and leaves ghosts behind. */
body.eink *, body.eink *::before, body.eink *::after {
  transition: none !important;
  animation: none !important;
}

.eink-flash {
  position: fixed;
  inset: 0;
  z-index: 999;
  background: #fff;
  pointer-events: none;
}

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