body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  margin: 0;
}

.game-container {
  background: white;
  padding: 2.5rem;
  border-radius: 20px;
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
  text-align: center;
  width: 350px;
}

h1 {
  color: #764ba2;
  margin-bottom: 0.5rem;
  letter-spacing: 2px;
}

p {
  color: #666;
  font-size: 0.9rem;
}

input {
  width: 100%;
  padding: 12px;
  margin: 10px 0;
  border: 2px solid #f0f0f0;
  border-radius: 8px;
  box-sizing: border-box;
  outline: none;
}

.btn-group {
  display: flex;
  gap: 10px;
  margin-top: 15px;
}

button {
  flex: 2;
  background: #764ba2;
  color: white;
  border: none;
  padding: 12px;
  border-radius: 8px;
  cursor: pointer;
  font-weight: bold;
  transition: 0.3s;
}

button:hover {
  opacity: 0.9;
}

.share-btn {
  background: #25d366;
  margin-top: 15px;
  width: 100%;
  display: none;
}

button.reset-btn {
  flex: 1;
  background: #f0f0f0;
  color: #333;
}

#result {
  margin-top: 25px;
  min-height: 50px;
}

@keyframes pulse {
  from {
    transform: scale(1);
  }
  to {
    transform: scale(1.03);
  }
}

.calculating {
  animation: pulse 0.6s infinite alternate;
}

@keyframes popIn {
  0% {
    transform: scale(0);
    opacity: 0;
  }
  100% {
    transform: scale(1);
    opacity: 1;
  }
}

.final-result {
  animation: popIn 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards;
  font-size: 1.8rem;
  font-weight: 800;
  color: #ff416c;
}

@media (max-width: 360px) {
  .game-container {
    width: 90%;
    padding: 1.5rem;
    border-radius: 15px;
  }

  h1 {
    font-size: 1.4rem;
    letter-spacing: 1px;
  }

  p {
    font-size: 0.8rem;
  }

  input,
  button {
    padding: 10px;
    font-size: 0.9rem;
  }

  .final-result {
    font-size: 1.4rem;
  }
}


@media (max-width: 480px) {

    .game-container {
        width: 85%;
        padding: 2rem;
    }

    h1 {
        font-size: 1.6rem;
    }

    p {
        font-size: 0.85rem;
    }

    input, button {
        font-size: 0.95rem;
    }

    .final-result {
        font-size: 1.6rem;
    }
}


@media (max-width: 720px) {

    .game-container {
        width: 400px;
        padding: 2.2rem;
    }

    h1 {
        font-size: 1.8rem;
    }

    .final-result {
        font-size: 1.7rem;
    }
}