:root {
  --bg-top: #f7f2e8;
  --bg-mid: #ecdfcc;
  --bg-bottom: #dcc2a0;
  --panel-bg: rgba(255, 250, 242, 0.84);
  --panel-border: rgba(255, 255, 255, 0.66);
  --board-bg: #a98864;
  --cell-bg: rgba(255, 239, 219, 0.3);
  --text: #312516;
  --light-text: #6e5a40;
  --btn-bg: #d25e3d;
  --btn-bg-hover: #b84a2c;
  --btn-shadow: 0 14px 26px rgba(145, 54, 31, 0.28);
  --shadow: 0 28px 60px rgba(78, 56, 31, 0.2);
  --board-size: min(70vh, 58vw, 760px);
  --panel-width: min(34vw, 420px);
  --gap: clamp(8px, 1.2vw, 14px);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  height: 100vh;
  overflow: hidden;
  font-family: "Optima", "Avenir Next", "Trebuchet MS", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 14% 10%, rgba(255, 255, 255, 0.66), transparent 38%),
    radial-gradient(circle at 86% 8%, rgba(255, 255, 255, 0.5), transparent 42%),
    linear-gradient(160deg, var(--bg-top), var(--bg-mid) 44%, var(--bg-bottom));
}

.page {
  height: 100vh;
  display: grid;
  grid-template-columns: minmax(280px, var(--panel-width)) minmax(320px, var(--board-size));
  align-items: center;
  justify-content: center;
  gap: clamp(18px, 2.4vw, 34px);
  padding: clamp(12px, 2.2vw, 24px);
}

.panel {
  width: 100%;
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  padding: clamp(16px, 2.2vw, 26px);
  box-shadow: var(--shadow);
  backdrop-filter: blur(8px);
}

.heading h1 {
  margin: 0 0 8px;
  font-size: clamp(2.2rem, 4.8vw, 4.2rem);
  line-height: 0.95;
  letter-spacing: 0.04em;
}

.heading p {
  margin: 0;
  color: var(--light-text);
  font-size: clamp(1rem, 1.4vw, 1.2rem);
}

.scores {
  margin-top: clamp(12px, 1.8vw, 18px);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(10px, 1.4vw, 14px);
}

.score-card {
  background: rgba(243, 224, 193, 0.84);
  border-radius: 14px;
  border: 1px solid rgba(255, 255, 255, 0.58);
  padding: clamp(10px, 1.6vw, 14px) 12px;
  text-align: center;
}

.score-card .label {
  display: block;
  font-size: clamp(0.72rem, 0.9vw, 0.86rem);
  text-transform: uppercase;
  color: #80684a;
  letter-spacing: 0.07em;
}

.score-card strong {
  display: block;
  margin-top: 3px;
  font-size: clamp(1.5rem, 2.3vw, 2.3rem);
  line-height: 1;
}

.primary-btn {
  border: 0;
  border-radius: 12px;
  background: var(--btn-bg);
  color: #fff;
  font-weight: 700;
  font-size: clamp(1rem, 1.2vw, 1.1rem);
  padding: clamp(10px, 1.4vw, 13px) clamp(16px, 2vw, 20px);
  cursor: pointer;
  margin-top: clamp(12px, 1.8vw, 18px);
  box-shadow: var(--btn-shadow);
  transition:
    transform 0.15s ease,
    background-color 0.2s ease,
    box-shadow 0.2s ease;
}

.primary-btn:hover {
  background: var(--btn-bg-hover);
  box-shadow: 0 16px 30px rgba(145, 54, 31, 0.35);
}

.primary-btn:active {
  transform: translateY(1px);
}

.board-wrap {
  width: min(100%, var(--board-size));
  position: relative;
}

.board {
  width: 100%;
  aspect-ratio: 1;
  padding: var(--gap);
  border-radius: 22px;
  background: var(--board-bg);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-template-rows: repeat(4, minmax(0, 1fr));
  gap: var(--gap);
  box-shadow: var(--shadow);
}

.tile {
  width: 100%;
  aspect-ratio: 1 / 1;
  border-radius: 14px;
  background: var(--cell-bg);
  display: grid;
  place-items: center;
  font-weight: 800;
  font-size: clamp(1.45rem, 2.8vw, 2.7rem);
  color: #5f4a35;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.34);
  animation: pop 0.15s ease;
}

.tile.empty {
  color: transparent;
  background: var(--cell-bg);
}

.tile.v2 {
  background: #f4ecdd;
}

.tile.v4 {
  background: #efdfc3;
}

.tile.v8 {
  background: #e9af6c;
  color: #fff;
}

.tile.v16 {
  background: #df9656;
  color: #fff;
}

.tile.v32 {
  background: #d77c4d;
  color: #fff;
}

.tile.v64 {
  background: #cc663f;
  color: #fff;
}

.tile.v128 {
  background: #debd65;
  color: #fff;
  font-size: clamp(1.16rem, 2.25vw, 2.02rem);
}

.tile.v256 {
  background: #d2b25a;
  color: #fff;
  font-size: clamp(1.16rem, 2.25vw, 2.02rem);
}

.tile.v512 {
  background: #c8a74f;
  color: #fff;
  font-size: clamp(1.16rem, 2.25vw, 2.02rem);
}

.tile.v1024 {
  background: #b7923d;
  color: #fff;
  font-size: clamp(0.96rem, 1.84vw, 1.62rem);
}

.tile.v2048 {
  background: #a37d2b;
  color: #fff;
  font-size: clamp(0.96rem, 1.84vw, 1.62rem);
}

.tile.vbig {
  background: #403132;
  color: #fff;
  font-size: clamp(0.85rem, 1.4vw, 1.08rem);
}

.overlay {
  position: absolute;
  inset: 0;
  z-index: 4;
  border-radius: 22px;
  background: rgba(44, 31, 17, 0.62);
  display: grid;
  place-content: center;
  text-align: center;
  color: #fff;
  gap: 10px;
  backdrop-filter: blur(2px);
}

.overlay h2 {
  margin: 0;
  font-size: clamp(1.3rem, 2vw, 2rem);
}

.hidden {
  display: none;
}

@keyframes pop {
  from {
    transform: scale(0.94);
    opacity: 0.78;
  }
  to {
    transform: scale(1);
    opacity: 1;
  }
}

@media (max-width: 980px) {
  :root {
    --board-size: min(52vh, 92vw, 520px);
  }

  body {
    overflow: auto;
  }

  .page {
    min-height: 100vh;
    height: auto;
    grid-template-columns: 1fr;
    justify-items: center;
    align-content: center;
    gap: 14px;
    padding: 14px;
  }

  .panel,
  .board-wrap {
    width: min(92vw, 560px);
  }

  .scores {
    grid-template-columns: 1fr;
  }

  .primary-btn {
    width: 100%;
  }
}