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

body {
  font-family: 'Arial', sans-serif;
  background-color: #333333;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  overflow: hidden;
  padding: 20px;
}

h1 {
  color: #f0f0f0;
  margin-bottom: 20px;
  font-size: clamp(28px, 6vw, 48px);
  text-shadow: none;
}

.score-container {
  display: flex;
  justify-content: center;
  gap: 40px;
  margin-bottom: 30px;
  flex-wrap: wrap;
}

.score-container div {
  background-color: #444444;
  padding: 12px 20px;
  border-radius: 8px;
  color: #f0f0f0;
  font-size: clamp(14px, 3vw, 18px);
  font-weight: bold;
  border: 1px solid #555555;
}

.score-container span {
  color: #ffd700;
  font-weight: bold;
}

.game-container {
  --cell-size: clamp(60px, 18vw, 100px);
  --cell-gap: clamp(8px, 2vw, 12px);

  background-color: rgba(50, 50, 50, 0.4);
  padding: var(--cell-gap);
  border-radius: clamp(8px, 2vw, 15px);
  backdrop-filter: blur(10px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.game-grid {
  display: grid;
  grid-template-columns: repeat(4, var(--cell-size));
  grid-template-rows: repeat(4, var(--cell-size));
  gap: var(--cell-gap);
  background-color: rgba(0, 0, 0, 0.1);
  padding: var(--cell-gap);
  border-radius: 8px;
}

.grid-cell {
  background-color: rgba(255, 255, 255, 0.1);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.grid-cell[data-value] {
  font-size: clamp(20px, 4vw, 40px);
  font-weight: bold;
  transition: all 0.1s ease-out;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.new-cell {
  animation: pop-in 0.2s ease-out;
}

@keyframes pop-in {
  0% {
    opacity: 0;
    transform: scale(0.5);
  }
  100% {
    opacity: 1;
    transform: scale(1);
  }
}

.merged-cell {
  animation: merge-scale 0.2s ease-out;
}

@keyframes merge-scale {
  0% {
    transform: scale(0.95);
  }
  50% {
    transform: scale(1.1);
  }
  100% {
    transform: scale(1);
  }
}

.grid-cell[data-value='2'] {
  background: linear-gradient(135deg, #eee4da 0%, #ede0c8 100%);
  color: #776e65;
}

.grid-cell[data-value='4'] {
  background: linear-gradient(135deg, #ede0c8 0%, #f2b179 100%);
  color: #f9f6f2;
}

.grid-cell[data-value='8'] {
  background: linear-gradient(135deg, #f2b179 0%, #f59563 100%);
  color: #f9f6f2;
  font-weight: bold;
}

.grid-cell[data-value='16'] {
  background: linear-gradient(135deg, #f59563 0%, #f67c5f 100%);
  color: #f9f6f2;
  font-weight: bold;
}

.grid-cell[data-value='32'] {
  background: linear-gradient(135deg, #f67c5f 0%, #f65e3b 100%);
  color: #f9f6f2;
  font-weight: bold;
}

.grid-cell[data-value='64'] {
  background: linear-gradient(135deg, #f65e3b 0%, #edcf72 100%);
  color: #f9f6f2;
  font-weight: bold;
}

.grid-cell[data-value='128'] {
  background: linear-gradient(135deg, #edcf72 0%, #edcc61 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(18px, 3.5vw, 35px);
}

.grid-cell[data-value='256'] {
  background: linear-gradient(135deg, #edcc61 0%, #edc850 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(18px, 3.5vw, 35px);
}

.grid-cell[data-value='512'] {
  background: linear-gradient(135deg, #edc850 0%, #edc53f 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(18px, 3.5vw, 35px);
}

.grid-cell[data-value='1024'] {
  background: linear-gradient(135deg, #edc22e 0%, #3c3c0c 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(16px, 3vw, 30px);
}

.grid-cell[data-value='2048'] {
  background: linear-gradient(135deg, #3d2817 0%, #000 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(16px, 3vw, 30px);
  box-shadow: 0 0 20px rgba(237, 194, 46, 0.5);
}

.grid-cell[data-value='4096'] {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(14px, 2.5vw, 25px);
}

.grid-cell[data-value='8192'] {
  background: linear-gradient(135deg, #764ba2 0%, #f093fb 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(14px, 2.5vw, 25px);
}

.grid-cell[data-value='16384'] {
  background: linear-gradient(135deg, #f093fb 0%, #4facfe 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(12px, 2vw, 20px);
}

.grid-cell[data-value]:not([data-value='2']):not([data-value='4']):not(
    [data-value='8']
  ):not([data-value='16']):not([data-value='32']):not([data-value='64']):not(
    [data-value='128']
  ):not([data-value='256']):not([data-value='512']):not([data-value='1024']):not(
    [data-value='2048']
  ):not([data-value='4096']):not([data-value='8192']):not([data-value='16384']) {
  background: linear-gradient(135deg, #30cfd0 0%, #330867 100%);
  color: #f9f6f2;
  font-weight: bold;
  font-size: clamp(7px, 1.2vw, 12px);
}

.game-over,
.win-overlay {
  display: none;
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 40px 30px;
  border-radius: 15px;
  color: #fff;
  z-index: 100;
  animation: modal-pop 0.3s ease-out;
  max-width: 90vw;
  text-align: center;
}

@keyframes modal-pop {
  0% {
    opacity: 0;
    transform: translate(-50%, -50%) scale(0.8);
  }
  100% {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1);
  }
}

.game-over::before,
.win-overlay::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: -1;
  border-radius: 15px;
}

.game-over {
  background-color: rgba(80, 50, 50, 0.95);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
}

.win-overlay {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  box-shadow: 0 10px 40px rgba(102, 126, 234, 0.5);
}

.game-over h2,
.win-overlay h2 {
  font-size: clamp(24px, 5vw, 40px);
  margin-bottom: 15px;
}

.game-over p,
.win-overlay p {
  font-size: clamp(14px, 3vw, 18px);
  margin-bottom: 25px;
  opacity: 0.95;
}

.restart-game-button,
.continue-button {
  padding: 12px 24px;
  cursor: pointer;
  background-color: #fff;
  border: none;
  border-radius: 8px;
  font-size: clamp(14px, 2.5vw, 18px);
  font-weight: bold;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
  margin-top: 10px;
}

.restart-game-button:hover,
.continue-button:hover {
  background-color: #f0f0f0;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

.restart-game-button:active,
.continue-button:active {
  transform: translateY(0);
}

.new-game-button {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  padding: 12px 28px;
  background-color: #555555;
  color: #f0f0f0;
  border: 2px solid #666666;
  border-radius: 8px;
  cursor: pointer;
  font-size: clamp(14px, 2.5vw, 16px);
  font-weight: bold;
  transition: all 0.3s ease;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
  z-index: 50;
}

.new-game-button:hover {
  background-color: #666666;
  transform: translateX(-50%) translateY(-2px);
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
}

.new-game-button:active {
  transform: translateX(-50%) translateY(0);
}

@media (max-width: 768px) {
  body {
    padding: 10px;
  }

  h1 {
    margin-bottom: 15px;
  }

  .score-container {
    gap: 20px;
    margin-bottom: 20px;
  }

  .game-container {
    padding: var(--cell-gap);
  }

  .game-over,
  .win-overlay {
    padding: 30px 20px;
    margin: 0 20px;
  }
}

@media (max-height: 600px) {
  body {
    padding: 10px;
  }

  h1 {
    margin-bottom: 10px;
  }

  .score-container {
    margin-bottom: 10px;
  }

  .new-game-button {
    bottom: 10px;
  }
}