:root {
  /* Surfaces / elevation */
  --bg-0: #0b0a16;
  --bg-1: #110f1f;
  --bg: #0b0a16;            /* legacy alias */
  --bg-2: #16142a;         /* panel-ish surface */
  --surface-1: #1a1730;
  --surface-2: #221d3d;
  --panel: #1a1730;         /* legacy alias */
  --void: #100e1c;
  --board-bg: #181b25;
  --cell-empty: #14161e;
  --cell-border: #2c3140;
  --hairline: #2a2545;
  --hairline-strong: #3a3360;
  --line: #2a2545;          /* legacy alias */

  /* Text */
  --text: #ece9fb;
  --text-dim: #a39ec6;
  --text-faint: #6f6992;
  --muted: #a39ec6;         /* legacy alias */

  /* Hero accent */
  --accent: #ffb43f;
  --accent-2: #ff7a4d;
  --accent-ink: #271403;
  --glow-accent: rgba(255, 180, 63, 0.45);

  /* Semantic */
  --solved: #4fd18b;
  --solved-glow: rgba(79, 209, 139, 0.5);
  --bad: #ff6b57;

  /* Pack hues (jewel-toned) */
  --amber: #ffc24d;
  --green: #5fd38a;
  --blue: #46c2dd;
  --purple: #9a8cff;
  --pink: #ff79a8;

  /* Radius scale */
  --r-sm: 8px;
  --r-md: 12px;
  --r-lg: 16px;
  --r-xl: 22px;
  --r-pill: 999px;

  /* Shadow scale */
  --sh-sm: 0 2px 8px rgba(0, 0, 0, 0.35);
  --sh-md: 0 10px 30px rgba(0, 0, 0, 0.42);
  --sh-lg: 0 24px 64px rgba(0, 0, 0, 0.58);

  /* Motion */
  --ease: cubic-bezier(.2, .8, .2, 1);
  --dur: .16s;

  --ad-height: 60px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  background:
    radial-gradient(1100px 680px at 82% -12%, rgba(124, 92, 255, 0.22) 0%, transparent 60%),
    radial-gradient(900px 620px at -12% 18%, rgba(70, 194, 221, 0.14) 0%, transparent 55%),
    radial-gradient(1000px 700px at 50% 120%, rgba(255, 122, 77, 0.12) 0%, transparent 58%),
    var(--bg-0);
  background-attachment: fixed;
  color: var(--text);
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-tap-highlight-color: transparent;
  overscroll-behavior: none;
  overflow: hidden;
}

/* Faint grain overlay */
body::before {
  content: "";
  position: fixed; inset: 0; z-index: -1; pointer-events: none;
  opacity: 0.04;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---- Banner Ad ---- */
.ad-banner {
  position: fixed; bottom: 0; left: 0; right: 0;
  height: var(--ad-height);
  background: rgba(8,7,16,.85); backdrop-filter: blur(8px);
  border-top: 1px solid var(--hairline);
  display: flex; align-items: center; justify-content: center;
  z-index: 900;
}
.ad-slot {
  width: 320px; height: 50px;
  background: var(--surface-1);
  border: 1px dashed var(--hairline-strong);
  border-radius: var(--r-md);
  display: flex; align-items: center; justify-content: center;
}
.ad-label {
  color: var(--muted); font-size: 11px; font-weight: 600;
  letter-spacing: 1px; text-transform: uppercase; opacity: .5;
}

/* ---- Screens ---- */
.screen {
  display: none;
  height: calc(100vh - var(--ad-height));
  height: calc(100dvh - var(--ad-height));
  overflow-y: auto;
}
.screen.active { display: block; }

/* ---- Menu Screen ---- */
.menu {
  max-width: 560px; margin: 0 auto;
  padding: 48px 24px calc(24px + var(--ad-height));
  position: relative;
}
.menu-brand {
  text-align: center; margin-bottom: 40px;
}
.menu-logo {
  font-size: 48px; display: block; margin-bottom: 10px;
  color: var(--accent);
  filter: drop-shadow(0 0 22px var(--glow-accent));
}
.menu-title, .brandname, #title, #header-title, #pack-name, .pack-name {
  font-family: "Space Grotesk", "Inter", system-ui, sans-serif;
}
.menu-title {
  font-weight: 700; letter-spacing: 6px; font-size: 34px;
  background: linear-gradient(135deg, #fff 0%, var(--accent) 55%, #ffd98a 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
  filter: drop-shadow(0 2px 18px var(--glow-accent));
}
.menu-tagline {
  color: var(--muted); font-size: 15px; margin-top: 6px;
}

.pack-grid {
  display: grid; grid-template-columns: 1fr; gap: 12px;
}
.pack-card {
  --pack: var(--accent);
  background:
    linear-gradient(135deg, color-mix(in srgb, var(--pack) 14%, transparent), transparent 60%),
    var(--surface-1);
  border: 1px solid var(--hairline);
  border-radius: var(--r-lg); padding: 20px 22px;
  cursor: pointer; transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  display: flex; align-items: center; gap: 18px;
  position: relative; overflow: hidden;
  box-shadow: var(--sh-sm);
}
.pack-card:hover {
  transform: translateY(-3px);
  border-color: color-mix(in srgb, var(--pack) 55%, var(--hairline));
  box-shadow: var(--sh-md), 0 0 28px color-mix(in srgb, var(--pack) 28%, transparent);
}
.pack-card::before {
  content: ""; position: absolute; left: 0; top: 0; bottom: 0;
  width: 4px; background: var(--pack);
  box-shadow: 0 0 16px color-mix(in srgb, var(--pack) 60%, transparent);
}
.pack-card[data-color="amber"]  { --pack: var(--amber); }
.pack-card[data-color="green"]  { --pack: var(--green); }
.pack-card[data-color="blue"]   { --pack: var(--blue); }
.pack-card[data-color="purple"] { --pack: var(--purple); }
.pack-card[data-color="pink"]   { --pack: var(--pink); }

.pack-icon {
  width: 58px; height: 58px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 30px; line-height: 1; flex-shrink: 0;
  background:
    radial-gradient(120% 120% at 30% 25%, color-mix(in srgb, var(--pack) 36%, transparent), color-mix(in srgb, var(--pack) 14%, transparent));
  box-shadow:
    inset 0 0 0 1.5px color-mix(in srgb, var(--pack) 45%, transparent),
    0 4px 14px color-mix(in srgb, var(--pack) 28%, transparent);
  transition: transform .25s var(--ease);
}
.pack-card:hover .pack-icon { transform: scale(1.08) rotate(-6deg); }

.pack-details { flex: 1; min-width: 0; }
.pack-name {
  font-weight: 700; font-size: 18px; letter-spacing: .2px;
  margin-bottom: 3px;
}
.pack-desc { color: var(--muted); font-size: 13px; margin-bottom: 10px; }
.pack-bar {
  height: 6px; background: var(--bg-0); border-radius: var(--r-pill); overflow: hidden;
  box-shadow: inset 0 0 0 1px var(--hairline);
}
.pack-bar-inner {
  height: 100%; border-radius: var(--r-pill); transition: width .5s var(--ease);
  background: linear-gradient(90deg, var(--pack), color-mix(in srgb, var(--pack) 60%, #fff));
  box-shadow: 0 0 10px color-mix(in srgb, var(--pack) 55%, transparent);
}
.pack-stat {
  color: var(--muted); font-size: 11px; font-weight: 600;
  margin-top: 4px;
}

/* ---- Pack Screen (puzzle list) ---- */
.pack-view {
  --pack: var(--accent);
  max-width: 720px; margin: 0 auto;
  padding: 28px 24px calc(24px + var(--ad-height));
  position: relative;
}
.pack-view[data-color="amber"]  { --pack: var(--amber); }
.pack-view[data-color="green"]  { --pack: var(--green); }
.pack-view[data-color="blue"]   { --pack: var(--blue); }
.pack-view[data-color="purple"] { --pack: var(--purple); }
.pack-view[data-color="pink"]   { --pack: var(--pink); }
.pack-header { margin-bottom: 28px; }
.pack-header .btn { margin-bottom: 16px; }
.pack-title-area { margin-bottom: 12px; }
#pack-name {
  font-size: 28px; font-weight: 700;
  background: linear-gradient(135deg, #fff 0%, var(--pack) 90%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.pack-progress-area { display: flex; align-items: center; gap: 14px; }

.puzzle-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 10px;
}
.puzzle-card {
  background:
    linear-gradient(135deg, color-mix(in srgb, var(--pack) 9%, transparent), transparent 55%),
    var(--surface-1);
  border: 1px solid var(--hairline);
  border-radius: var(--r-lg); padding: 16px 18px;
  cursor: pointer; transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  position: relative; box-shadow: var(--sh-sm);
}
.puzzle-card:hover {
  transform: translateY(-3px) scale(1.015);
  border-color: color-mix(in srgb, var(--pack) 55%, var(--hairline));
  box-shadow: var(--sh-md), 0 0 22px color-mix(in srgb, var(--pack) 24%, transparent);
}
.puzzle-card.completed {
  border-color: color-mix(in srgb, var(--solved) 60%, var(--hairline));
  box-shadow: 0 0 16px color-mix(in srgb, var(--solved) 22%, transparent);
}
.puzzle-num {
  display: inline-block;
  font-size: 11px; font-weight: 800; letter-spacing: .5px;
  color: var(--pack);
  background: color-mix(in srgb, var(--pack) 16%, transparent);
  box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--pack) 32%, transparent);
  padding: 2px 8px; border-radius: var(--r-pill);
  margin-bottom: 8px;
}
.puzzle-clue {
  font-size: 14px; font-weight: 700; line-height: 1.3;
  margin-bottom: 4px;
}
.puzzle-hint {
  font-size: 12px; color: var(--muted); line-height: 1.3;
}
.puzzle-check {
  position: absolute; top: 12px; right: 14px;
  color: var(--solved); font-size: 18px; font-weight: 700;
  display: none;
}
.puzzle-card.completed .puzzle-check { display: block; }

/* ---- Back button in game ---- */
.back-btn {
  background: var(--surface-1); border: 1px solid var(--hairline);
  color: var(--text-dim); width: 34px; height: 34px;
  border-radius: var(--r-md); font-size: 16px; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.back-btn:hover { color: var(--text); border-color: var(--hairline-strong); background: var(--surface-2); }

/* ---- Game Shell ---- */
.app {
  max-width: 1100px;
  margin: 0 auto;
  height: calc(100vh - var(--ad-height));
  height: calc(100dvh - var(--ad-height));
  padding: 14px 20px 10px;
  display: flex; flex-direction: column;
  overflow: hidden;
}

/* Top bar */
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 12px; flex: none; position: relative;
}
.brand { display: flex; align-items: center; gap: 10px; }
.logo {
  font-size: 22px; color: var(--accent);
  filter: drop-shadow(0 0 12px var(--glow-accent));
}
.brandname {
  font-weight: 700; letter-spacing: 3px; font-size: 15px; color: var(--text);
}
.header-title {
  display: none;
  font-weight: 800; font-size: 16px; color: var(--text);
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  min-width: 0;
}
.controls { display: flex; gap: 10px; }

/* Hamburger menu button — hidden on desktop */
.menu-btn {
  display: none;
  background: var(--surface-1); border: 1px solid var(--hairline);
  color: var(--text-dim); width: 34px; height: 34px;
  border-radius: var(--r-md); font-size: 18px; cursor: pointer;
  align-items: center; justify-content: center;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.menu-btn:hover { color: var(--text); border-color: var(--hairline-strong); background: var(--surface-2); }

/* Theme toggle (icon button) */
.theme-toggle {
  background: var(--surface-1); border: 1px solid var(--hairline);
  color: var(--text-dim); width: 34px; height: 34px;
  border-radius: var(--r-md); font-size: 15px; cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.theme-toggle:hover { color: var(--accent); border-color: var(--hairline-strong); background: var(--surface-2); }
.menu-theme-toggle { position: absolute; top: 16px; right: 16px; z-index: 5; }
.pack-theme-toggle { position: absolute; top: 20px; right: 20px; z-index: 5; }
.menu-dropdown {
  display: none; position: absolute; top: 100%; right: 0;
  background: var(--surface-2); border: 1px solid var(--hairline-strong);
  border-radius: var(--r-lg); padding: 14px; min-width: 200px;
  box-shadow: var(--sh-lg);
  z-index: 100; margin-top: 6px;
  flex-direction: column; gap: 12px;
}
.menu-dropdown.open { display: flex; }
.menu-dropdown-label {
  font-size: 11px; font-weight: 700; color: var(--text-dim);
  letter-spacing: .5px; text-transform: uppercase;
}
.menu-dropdown-section {
  display: flex; flex-direction: column; gap: 6px;
}
.menu-dropdown .mode-toggle { width: 100%; display: flex; }
.menu-dropdown .mode-btn { flex: 1; text-align: center; }
.mdd-mode[data-mode="hard"].active { background: var(--bad); color: #2a0c06; }

.btn {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: var(--accent-ink); border: none;
  padding: 9px 16px; border-radius: var(--r-md); font-weight: 800; font-size: 13px;
  cursor: pointer; transition: transform var(--dur) var(--ease), filter var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  letter-spacing: .3px;
  box-shadow: 0 4px 14px color-mix(in srgb, var(--accent) 35%, transparent);
}
.btn:hover { filter: brightness(1.06); transform: translateY(-1px); box-shadow: 0 6px 20px var(--glow-accent); }
.btn:active { transform: translateY(0); }
.ghost-btn {
  background: transparent; color: var(--text-dim);
  border: 1px solid var(--hairline-strong);
  box-shadow: none;
}
.ghost-btn:hover { color: var(--text); border-color: var(--text-faint); filter: none; box-shadow: none; }

.mode-toggle {
  display: inline-flex; padding: 3px; gap: 3px;
  background: var(--surface-1); border: 1px solid var(--hairline); border-radius: var(--r-md);
}
.mode-btn {
  background: transparent; color: var(--text-dim); border: none;
  padding: 6px 14px; border-radius: var(--r-sm); font-weight: 700; font-size: 12px;
  letter-spacing: .3px; cursor: pointer; transition: all var(--dur) var(--ease);
}
.mode-btn:hover { color: var(--text); }
.mode-btn.active { background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: var(--accent-ink); }
#mode-hard.active { background: var(--bad); color: #2a0c06; }

/* Puzzle meta */
.puzzle-meta { margin-bottom: 10px; flex: none; }
#title {
  font-size: 26px; font-weight: 800; letter-spacing: -.5px;
  background: linear-gradient(135deg, #fff 0%, #b0b8d0 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hint { color: var(--muted); font-size: 13px; margin-top: 3px; }
.progress-row { display: flex; align-items: center; gap: 14px; margin-top: 10px; }
.bar {
  flex: 1; height: 6px; background: var(--panel);
  border-radius: 99px; overflow: hidden; border: 1px solid var(--line);
}
.bar-fill {
  height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--solved));
  transition: width .4s cubic-bezier(.2,.8,.2,1);
}
.progress { color: var(--muted); font-size: 13px; font-weight: 600; min-width: 84px; text-align: right; }

.hint-btn {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: var(--accent-ink); border: none;
  padding: 6px 14px; border-radius: var(--r-pill);
  font-weight: 800; font-size: 12px; letter-spacing: .4px;
  cursor: pointer; flex: none;
  box-shadow: 0 4px 14px var(--glow-accent);
  transition: transform var(--dur) var(--ease), filter var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.hint-btn:hover:not(:disabled) { filter: brightness(1.06); transform: translateY(-1px); box-shadow: 0 6px 18px var(--glow-accent); }
.hint-btn:active { transform: translateY(0); }
.hint-btn:disabled { opacity: .55; cursor: default; box-shadow: none; }

.ad-banner.hidden { display: none; }

/* ---- Play area ---- */
.play {
  flex: 1; min-height: 0;
  display: flex; flex-direction: column; gap: 10px;
}
.layout-side .play {
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(200px, 320px);
  grid-template-rows: minmax(0, 1fr); gap: 20px;
  align-items: stretch;
}

/* Board */
.board-wrap {
  background: var(--board-bg);
  border: 1px solid var(--hairline);
  border-radius: var(--r-lg);
  padding: 12px;
  display: flex; flex-direction: column;
  justify-content: center; align-items: center;
  min-height: 0; overflow: hidden;
  box-shadow: var(--sh-md), inset 0 1px 0 rgba(255,255,255,.03);
  flex: 1 1 0;
}
.board {
  display: grid; gap: 3px;
  touch-action: none;
}
.cell {
  border-radius: var(--r-sm);
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; user-select: none;
}
.cell.void { background: transparent; }
.cell.white {
  background: var(--cell-empty);
  box-shadow: inset 0 0 0 1px var(--cell-border);
}
.cell.filled {
  color: #fff;
  text-shadow: 0 1px 2px rgba(0,0,0,.5);
  background-image: linear-gradient(180deg, rgba(255,255,255,.20), rgba(0,0,0,.22));
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,.28),
    inset 0 -2px 5px rgba(0,0,0,.30),
    inset 0 0 0 1px rgba(0,0,0,.14),
    0 2px 6px rgba(0,0,0,.3);
  animation: pop .18s var(--ease);
}
.cell.solved {
  box-shadow: inset 0 0 0 2px var(--solved), 0 0 18px var(--solved-glow);
  filter: saturate(1.2) brightness(1.05);
}
.cell.preview-ok { box-shadow: inset 0 0 0 2px var(--solved); background: color-mix(in srgb, var(--solved) 20%, transparent); }
.cell.preview-bad { box-shadow: inset 0 0 0 2px var(--bad); background: color-mix(in srgb, var(--bad) 18%, transparent); }
.cell.hint {
  color: var(--accent);
  font-weight: 800;
  text-shadow: 0 0 8px var(--glow-accent);
  animation: hintpulse 1.8s var(--ease) infinite;
}
@keyframes pop { from { transform: scale(.78); } to { transform: scale(1); } }
@keyframes hintpulse { 0%, 100% { opacity: .45; } 50% { opacity: .85; } }

/* ---- Tray ---- */
.tray-wrap {
  background: var(--bg-1);
  border: 1px solid var(--hairline);
  border-radius: var(--r-lg); padding: 10px 12px;
  box-shadow: var(--sh-md), inset 0 1px 0 rgba(255,255,255,.03);
  display: flex; flex-direction: column;
  min-height: 80px; overflow: hidden;
  flex: 0 1 auto; max-height: 42vh;
  position: relative;
}
.tray-wrap::after {
  content: ""; position: absolute; bottom: 0; left: 0; right: 0;
  height: 32px; pointer-events: none;
  background: linear-gradient(transparent, var(--bg-1));
  border-radius: 0 0 var(--r-lg) var(--r-lg);
  opacity: 0; transition: opacity .2s;
}
.tray-wrap.has-scroll::after { opacity: 1; }
.layout-side .tray-wrap { max-height: none; flex: 1; }
.tray-head {
  display: flex; align-items: baseline; justify-content: space-between;
  margin-bottom: 10px; flex: none;
}
.tray-head span:first-child { font-weight: 700; font-size: 14px; letter-spacing: .5px; }
.tray-tip { color: var(--muted); font-size: 11px; }
.tray {
  display: flex; flex-wrap: wrap; gap: 8px;
  justify-content: center; align-content: flex-start;
  flex: 1; min-height: 0; overflow-y: auto; overflow-x: hidden;
  scrollbar-width: thin; scrollbar-color: var(--line) transparent;
}
.layout-side .tray { justify-content: flex-start; align-content: flex-start; }
.tray-empty { color: var(--muted); font-size: 13px; padding: 20px 0; width: 100%; text-align: center; }

/* ---- Pieces ---- */
.piece {
  display: grid; gap: 2px; cursor: grab;
  padding: 4px; border-radius: var(--r-md);
  background: rgba(255,255,255,.035);
  border: 1px solid rgba(255,255,255,.05);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  touch-action: none;
  user-select: none; -webkit-user-select: none; -webkit-touch-callout: none;
}
.cell, .pblock { -webkit-user-select: none; -webkit-touch-callout: none; }
body.dragging { overflow: hidden; touch-action: none; }
.piece:hover {
  transform: translateY(-3px);
  box-shadow: var(--sh-md);
  border-color: rgba(255,255,255,.12);
}
.piece:active { cursor: grabbing; }
.pblock {
  border-radius: var(--r-sm); display: flex; align-items: center; justify-content: center;
  font-weight: 900;
  color: #fff;
  text-shadow: 0 1px 2px rgba(0,0,0,.5);
  background-image: linear-gradient(180deg, rgba(255,255,255,.22), rgba(0,0,0,.22));
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,.30),
    inset 0 -2px 5px rgba(0,0,0,.28),
    inset 0 0 0 1px rgba(0,0,0,.12),
    0 2px 5px rgba(0,0,0,.28);
}
.pgap { background: transparent; }

/* Ghost (dragged) */
.ghost {
  position: fixed; z-index: 999; pointer-events: none;
  filter: drop-shadow(0 12px 28px rgba(0,0,0,.55));
  opacity: .95;
}

/* ---- Win overlay ---- */
.win-overlay {
  position: fixed; inset: 0; display: none;
  align-items: center; justify-content: center;
  background: rgba(6,5,14,.74); backdrop-filter: blur(8px);
  z-index: 1000;
}
.win-overlay.show { display: flex; animation: fade .3s var(--ease); }
@keyframes fade { from { opacity: 0; } to { opacity: 1; } }
.win-card {
  position: relative; overflow: hidden;
  background:
    radial-gradient(120% 90% at 50% -10%, color-mix(in srgb, var(--accent) 18%, transparent), transparent 60%),
    var(--surface-2);
  border: 1px solid var(--hairline-strong);
  padding: 44px 48px; border-radius: var(--r-xl); text-align: center;
  box-shadow: var(--sh-lg), 0 0 60px color-mix(in srgb, var(--accent) 16%, transparent);
  animation: winpop .4s var(--ease);
}
@keyframes winpop { from { transform: scale(.9) translateY(10px); opacity: 0; } to { transform: scale(1) translateY(0); opacity: 1; } }
.win-emoji {
  font-size: 56px; color: var(--accent);
  filter: drop-shadow(0 0 22px var(--glow-accent));
  display: inline-block; animation: starspin 1.2s var(--ease);
}
@keyframes starspin { from { transform: rotate(-180deg) scale(0); } to { transform: rotate(0) scale(1); } }
.win-card h2 {
  font-family: "Space Grotesk", "Inter", sans-serif;
  font-size: 30px; margin: 10px 0 6px;
  background: linear-gradient(135deg, #fff, var(--accent));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.win-card p { color: var(--text-dim); margin-bottom: 22px; }

/* ---- Responsive ---- */
@media (min-width: 600px) {
  .pack-grid { grid-template-columns: 1fr; }
  .puzzle-grid { grid-template-columns: 1fr 1fr 1fr; }
  .ad-slot { width: 468px; height: 60px; }
  :root { --ad-height: 70px; }
}
@media (min-width: 900px) {
  .ad-slot { width: 728px; height: 90px; }
  :root { --ad-height: 100px; }
}
@media (max-width: 760px) {
  .app { padding: 6px 6px 4px; }

  .topbar { margin-bottom: 4px; gap: 8px; position: relative; }
  .brand { flex: 1; min-width: 0; }
  .logo { font-size: 19px; flex: none; }
  .brandname { display: none; }
  .header-title { display: block; }
  .controls { display: none; }
  .menu-btn { display: flex; flex: none; }

  .puzzle-meta { margin-bottom: 4px; }
  #title { display: none; }
  .hint { font-size: 11px; margin-top: 0; }
  .progress-row { margin-top: 4px; gap: 10px; }
  .bar { height: 5px; }
  .progress { font-size: 11px; min-width: 70px; }

  .play { gap: 6px; }
  .board-wrap { padding: 4px; border-radius: 10px; }
  .tray-wrap { padding: 6px 8px; border-radius: 10px; max-height: 38vh; }
  .tray-head { margin-bottom: 4px; }
  .tray-head span:first-child { font-size: 12px; }
  .tray-tip { font-size: 10px; }
  .tray { gap: 6px; }

  .win-card { padding: 32px 28px; margin: 0 16px; }
  .win-card h2 { font-size: 24px; }

  .menu { padding: 32px 16px 24px; }
  .menu-title { font-size: 24px; letter-spacing: 4px; }
  .menu-brand { margin-bottom: 28px; }
  .pack-icon { width: 42px; height: 42px; font-size: 19px; }
  .pack-name { font-size: 15px; }
  .pack-card { padding: 16px 16px; gap: 14px; }

  .pack-view { padding: 20px 16px 24px; }
  #pack-name { font-size: 22px; }
  .puzzle-grid { grid-template-columns: 1fr; }
  .puzzle-card { padding: 14px 16px; }
}

/* ====================== Light theme ====================== */
html[data-theme="light"] {
  --bg-0: #edecf3;
  --bg-1: #ffffff;
  --bg: #edecf3;
  --bg-2: #ffffff;
  --surface-1: #ffffff;
  --surface-2: #f6f5fb;
  --panel: #ffffff;
  --void: #e6e4ef;
  --board-bg: #e4e2ee;
  --cell-empty: #ffffff;
  --cell-border: #d3cfe4;
  --hairline: #ddd9ec;
  --hairline-strong: #c6c1da;
  --line: #ddd9ec;

  --text: #1b1930;
  --text-dim: #5b5676;
  --text-faint: #8a85a0;
  --muted: #5b5676;

  --accent: #f6a821;
  --accent-2: #f97316;
  --accent-ink: #2a1602;
  --glow-accent: rgba(246, 168, 33, 0.35);

  --solved: #2faa68;
  --solved-glow: rgba(47, 170, 104, 0.4);
  --bad: #e5533f;

  --sh-sm: 0 2px 8px rgba(40, 35, 70, 0.10);
  --sh-md: 0 10px 30px rgba(40, 35, 70, 0.12);
  --sh-lg: 0 24px 64px rgba(40, 35, 70, 0.18);
}

html[data-theme="light"] body {
  background:
    radial-gradient(1100px 680px at 82% -12%, rgba(124, 92, 255, 0.10) 0%, transparent 60%),
    radial-gradient(900px 620px at -12% 18%, rgba(70, 194, 221, 0.08) 0%, transparent 55%),
    radial-gradient(1000px 700px at 50% 120%, rgba(255, 150, 60, 0.08) 0%, transparent 58%),
    var(--bg-0);
  background-attachment: fixed;
}
html[data-theme="light"] body::before { opacity: 0.025; }

/* Titles that used white-based gradients need dark text on light */
html[data-theme="light"] #pack-name,
html[data-theme="light"] #title,
html[data-theme="light"] .win-card h2 {
  background: none;
  -webkit-text-fill-color: var(--text);
  color: var(--text);
}
html[data-theme="light"] .menu-title {
  background: linear-gradient(135deg, #2a2742, var(--accent));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}

html[data-theme="light"] .piece {
  background: rgba(0, 0, 0, 0.025);
  border-color: rgba(0, 0, 0, 0.07);
}
html[data-theme="light"] .ad-banner { background: rgba(255, 255, 255, 0.85); }