:root {
  --bg-gradient-start: #1f2937;
  --bg-gradient-end: #111827;
  --card-bg: #1f2937;
  --text-primary: #e5e7eb;
  --text-secondary: #9ca3af;
  --accent-primary: #3b82f6;
  --accent-primary-hover: #2563eb;
  --accent-danger: #ef4444;
  --accent-danger-hover: #dc2626;
  --border-color: #374151;

  --font-family: 'Segoe UI', 'Roboto', 'Helvetica Neue', sans-serif;
  --border-radius: 0.75rem;
  --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --transition-speed: 0.2s ease-in-out;
}

body {
  margin: 0;
  font-family: var(--font-family);
  background: linear-gradient(to bottom right, var(--bg-gradient-start), var(--bg-gradient-end));
  color: var(--text-primary);
  padding: 24px;
}

.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
}

.header {
  font-size: 2rem;
  font-weight: 600;
  margin-bottom: 0;
}

.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
}

.margin-top {
  margin-top: 1.5rem;
}

.card {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: var(--border-radius);
  box-shadow: var(--card-shadow);
  border: 1px solid var(--border-color);
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.card h2 {
  margin-top: 0;
  margin-bottom: 1rem;
  color: var(--text-primary);
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.75rem;
}

.stat {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--accent-primary);
}

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background: var(--accent-primary);
  border: none;
  border-radius: var(--border-radius);
  color: white;
  font-weight: 600;
  cursor: pointer;
  text-align: center;
  transition: background-color var(--transition-speed);
}

.header-container .btn {
  margin-top: 0;
}

.card .btn {
  margin-top: 0.5rem;
}

.btn:hover {
  background: var(--accent-primary-hover);
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--accent-primary);
  color: var(--accent-primary);
}

.btn-outline:hover {
  background: var(--accent-primary);
  color: white;
}

.btn-danger {
  background: var(--accent-danger);
}

.btn-danger:hover {
  background: var(--accent-danger-hover);
}

.profile-info {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.profile img {
  border-radius: 50%;
  width: 60px;
  height: 60px;
  border: 2px solid var(--accent-primary);
}

#achievementList {
    list-style: none;
    padding-left: 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}

th, td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

thead th {
  color: var(--text-secondary);
  font-weight: 600;
}

tbody tr:hover {
  background-color: #2a3a50;
}

.chat-box {
  height: 200px;
  overflow-y: auto;
  background: #111827;
  padding: 10px;
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  border-radius: var(--border-radius);
  margin-bottom: 1rem;
}

.d-flex {
  display: flex;
  gap: 0.5rem;
}

.form-control {
  flex-grow: 1;
  background: #2a3a50;
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 0.75rem;
  border-radius: var(--border-radius);
}

.form-control::placeholder {
  color: var(--text-secondary);
}

.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.6);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 1000;
  opacity: 0;
  transition: opacity 0.3s ease-in-out;
}

.modal-overlay.show {
  display: flex;
  opacity: 1;
}

.modal-content {
  background: var(--card-bg);
  padding: 2rem;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  box-shadow: 0 5px 15px rgba(0,0,0,0.5);
  text-align: center;
  max-width: 400px;
  width: 90%;
}

.modal-content h2 {
  margin-top: 0;
}

.modal-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 1.5rem;
}