body {
  background-color: #000000;
  color: #e0d7f5;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  padding: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.bg-gif {
  position: fixed;
  width: 150px;
  height: auto;
  z-index: -1;
  pointer-events: none;
  opacity: 0.8;
}

.top-left {
  top: 0;
  left: 0;
}

.bottom-right {
  bottom: 0;
  right: 0;
}

.container {
  max-width: 600px;
  padding: 2rem;
  background-color: #3b1f6b;
  border-radius: 12px;
  text-align: center;
  box-shadow: 0 0 20px rgba(148, 0, 211, 0.6);
}

h1 {
  color: #b085f5;
  margin-bottom: 1rem;
}

button {
  padding: 10px 20px;
  margin: 8px 5px;
  background-color: #9f7bff;
  color: white;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  transition: background-color 0.3s ease;
}

button:hover {
  background-color: #b285ff;
}

.hint-button {
  background-color: #5a3399;
  margin: 8px 5px;
  padding: 5px 10px;
  font-size: 0.9rem;
  border-radius: 4px;
}

.hint-button:hover {
  background-color: #7d4de1;
}

.hint {
  margin: 5px 0 0 0;
  font-style: italic;
  color: #cfc3ff;
  font-size: 0.9rem;
}

.hidden {
  display: none;
}

input {
  padding: 10px;
  width: 80%;
  margin: 15px 0;
  border-radius: 5px;
  border: none;
  font-size: 1rem;
  background-color: #cfc3ff;
  color: #000000;
  text-align: center;
}

input:disabled {
  background-color: #a998e6;
  color: #4a397a;
}

.hidden-popup {
  background-color: #5a3399;
  display: none;
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: rgba(0, 0, 0, 0.8);
  padding: 5px 10px;
  border-radius: 4px;
  z-index: 9999;
}

.hidden-popup img {
  max-width: 300px;
  border-radius: 8px;
}

.feedback {
  margin-top: 10px;
  font-weight: 700;
  font-size: 1.1rem;
}

.level {
  margin-top: 2rem;
}

table#sudokubox {
  margin: 25px auto;
  border-collapse: collapse;
  background-color: #f3e8ff;
  border: 5px solid #2a1a4d;
  border-radius: 8px;
}

table#sudokubox td {
  width: 50px;
  height: 50px;
  padding: 2px;
  border: 3px solid #2a1a4d;
}

table#sudokubox tr:nth-child(2) td,
table#sudokubox tr:nth-child(4) td {
  border-top: 5px solid #2a1a4d;
}

table#sudokubox td:nth-child(2),
table#sudokubox td:nth-child(4) {
  border-left: 5px solid #2a1a4d;
}

table#sudokubox input {
  width: 100%;
  height: 100%;
  border: none;
  font-size: 1.3rem;
  font-weight: bold;
  text-align: center;
  background-color: #f7e6ff;
  color: #2a1a4d;
}

table#sudokubox input:disabled {
  background-color: #b399ff;
  color: #1a0d33;
  font-weight: bold;
}