body {
  margin: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: #f8f9fa;
}

.container {
  margin-top: 100px;
  margin-bottom: 100px;
}

h1 {
  text-align: center;
  margin-bottom: 30px;
  color: #343a40;
}

.ranking-table {
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  border-collapse: collapse;
  background: white;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.ranking-table th,
.ranking-table td {
  padding: 14px 16px;
  text-align: left;
  vertical-align: top;
}

.ranking-table th {
  background-color: #343a40;
  color: white;
  text-transform: uppercase;
  font-size: 0.85em;
  letter-spacing: 0.5px;
}

.ranking-table tr:nth-child(even) {
  background-color: #f1f3f5;
}

.ranking-table td.score {
  font-weight: bold;
}

.highlight {
  background-color: #d1e7dd !important;
}

.btn-toggle {
  padding: 6px 10px;
  background-color: #007bff;
  color: white;
  text-decoration: none;
  font-size: 0.85em;
  border-radius: 6px;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.btn-toggle:hover {
  background-color: #0056b3;
}

.solution-row {
  display: none;
  background: #f8f9fa;
}

.solution-cell {
  padding: 20px;
  font-family: monospace;
  white-space: pre-wrap;
  border-top: 1px solid #dee2e6;
}

.back-link {
  text-align: center;
  margin-top: 30px;
}

.back-link a {
  text-decoration: none;
  color: #007bff;
}

.back-link a:hover {
  text-decoration: underline;
}