:root {
  color-scheme: light;
  font-family: "Be Vietnam Pro", Inter, ui-sans-serif, system-ui, sans-serif;
  --ink: #0f172a;
  --muted: #526070;
  --panel: rgba(255, 255, 255, 0.94);
  --line: #c0cad8;
  --block: #122033;
  --cell: #f8fbff;
  --accent: #0ea5e9;
  --accent-dark: #075985;
  --ok: #16a34a;
  --bad: #e11d48;
  --surface: #f8fafc;
  --shadow: 0 24px 70px rgba(2, 8, 23, 0.14);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    linear-gradient(90deg, rgba(255, 255, 255, 0.55) 1px, transparent 1px),
    linear-gradient(rgba(255, 255, 255, 0.55) 1px, transparent 1px),
    radial-gradient(circle at 85% 15%, rgba(14, 165, 233, 0.28), transparent 28%),
    radial-gradient(circle at 12% 82%, rgba(250, 204, 21, 0.18), transparent 25%),
    linear-gradient(135deg, #e0f2fe 0%, #f8fafc 48%, #dcfce7 100%);
  background-size: 28px 28px, 28px 28px, auto, auto, auto;
}

button { font: inherit; }

.app { max-width: 1220px; margin: 0 auto; padding: 18px 16px 34px; }
.topbar { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 92px; margin-bottom: 14px; }
.brand {
  color: var(--ink);
  text-decoration: none;
  font-weight: 900;
  background: rgba(255, 255, 255, 0.76);
  border: 1px solid rgba(15, 23, 42, 0.1);
  border-radius: 999px;
  padding: 10px 14px;
}

h1, h2, p { margin-top: 0; }
h1 { margin-bottom: 0; font-size: clamp(2.15rem, 5vw, 4.4rem); line-height: 0.95; }
h2 { margin-bottom: 8px; font-size: clamp(1.2rem, 2vw, 1.75rem); line-height: 1.14; }
p { color: var(--muted); line-height: 1.6; }
.eyebrow {
  margin-bottom: 8px;
  color: var(--accent-dark);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.layout { display: grid; gap: 14px; }
.panel {
  border: 1px solid rgba(15, 23, 42, 0.1);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}
.intro-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(430px, 0.82fr);
  align-items: end;
  gap: 18px;
  padding: 18px;
}
.intro-panel p { max-width: 760px; margin-bottom: 0; }
.game-panel { padding: 14px; overflow: hidden; }

.score-strip { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; }
.score-strip span {
  display: grid;
  gap: 4px;
  border: 1px solid rgba(15, 23, 42, 0.1);
  border-radius: 8px;
  background: var(--surface);
  padding: 12px;
  color: var(--muted);
  font-weight: 800;
}
.score-strip strong { color: var(--ink); font-size: 1.45rem; line-height: 1; }

.toolbar {
  display: grid;
  grid-template-columns: minmax(210px, max-content) 1fr auto auto auto auto;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}
.level-tabs { display: flex; flex-wrap: wrap; gap: 8px; }
.level-button, .primary-button, .secondary-button, .number-button {
  min-height: 42px;
  border: 1px solid rgba(15, 23, 42, 0.12);
  border-radius: 8px;
  padding: 10px 13px;
  cursor: pointer;
  font-weight: 900;
  transition: transform 0.16s ease, box-shadow 0.16s ease, background 0.16s ease;
}
.level-button, .secondary-button, .number-button { background: #fff; color: var(--ink); }
.primary-button, .level-button.active {
  background: var(--accent);
  color: white;
  border-color: transparent;
  box-shadow: 0 10px 24px rgba(14, 165, 233, 0.24);
}
.level-button:hover, .secondary-button:hover, .number-button:hover { transform: translateY(-1px); }
.number-button.active { outline: 3px solid rgba(14, 165, 233, 0.28); }

.board-wrap {
  overflow: auto;
  display: grid;
  justify-content: center;
  border: 1px solid rgba(15, 23, 42, 0.1);
  border-radius: 8px;
  background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
  padding: clamp(12px, 3vw, 26px);
}
.board {
  display: grid;
  grid-template-columns: repeat(var(--size), var(--cell-size));
  grid-auto-rows: var(--cell-size);
  gap: 2px;
  width: max-content;
  min-width: auto;
  justify-content: center;
}

.cell {
  position: relative;
  width: var(--cell-size);
  height: var(--cell-size);
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}
.cell.block { background: var(--block); color: #dbeafe; }
.cell.play {
  display: grid;
  place-items: center;
  background: var(--cell);
  color: var(--ink);
  font-size: clamp(1.1rem, 4vw, 1.7rem);
  font-weight: 900;
  cursor: pointer;
}
.cell.play.selected { outline: 3px solid var(--accent); outline-offset: -3px; box-shadow: inset 0 0 0 2px #fff; }
.cell.play.related { background: #e0f2fe; }
.cell.play.error { background: #ffe4e6; color: var(--bad); }
.cell.play.correct { color: var(--ok); }

.clue-line {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 49%, rgba(255, 255, 255, 0.34) 50%, transparent 51%);
}
.clue-down, .clue-right {
  position: absolute;
  font-size: clamp(0.58rem, 2.1vw, 0.78rem);
  font-weight: 900;
  line-height: 1;
}
.clue-down { left: 7px; bottom: 7px; }
.clue-right { right: 7px; top: 7px; }

.number-pad {
  display: grid;
  grid-template-columns: repeat(9, minmax(34px, 1fr));
  gap: 8px;
  margin-top: 14px;
  border: 1px solid rgba(15, 23, 42, 0.08);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.64);
  padding: 10px;
}
.number-button { min-width: 0; padding-inline: 8px; font-size: 1.05rem; }

.status {
  min-height: 44px;
  margin-top: 12px;
  border-radius: 8px;
  background: #eff6ff;
  border: 1px solid rgba(14, 165, 233, 0.18);
  padding: 12px;
  color: var(--muted);
  font-weight: 800;
}

@media (max-width: 860px) {
  .intro-panel { grid-template-columns: 1fr; }
  .score-strip { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .toolbar { grid-template-columns: 1fr 1fr; }
  .topbar { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 560px) {
  .app { padding-inline: 10px; }
  .intro-panel, .game-panel { padding: 12px; }
  .score-strip { grid-template-columns: 1fr; }
  .level-button, .primary-button, .secondary-button { flex: 1 1 auto; padding-inline: 10px; }
  .number-pad { grid-template-columns: repeat(5, minmax(44px, 1fr)); }
  .toolbar { grid-template-columns: 1fr; }
  .level-tabs { display: grid; grid-template-columns: repeat(3, 1fr); }
  .board-wrap { justify-content: start; }
}