html, body {
  background-color: #1c1c1c;
  color-scheme: dark;
  margin: 0;
  padding: 0;
  font-family: "MS Sans Serif", "Segoe UI", "Arial", sans-serif;
  color: #e0e0e0;
}

/* 标题栏 */
.window-title-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: #003366;
  color: #ffffff;
  padding: 6px 10px;
  font-size: 14px;
  font-weight: bold;
  border: 2px solid #555555;
  box-shadow: inset -1px -1px #444444, inset 1px 1px #000000;
  margin-bottom: 10px;
}

.window-controls {
  display: flex;
  gap: 6px;
}

.window-controls .btn {
  width: 18px;
  height: 18px;
  text-align: center;
  line-height: 16px;
  background: #1c1c1c;
  border: 1px solid #555555;
  color: #ffffff;
  font-size: 12px;
  cursor: pointer;
}

.window-controls .btn:hover {
  background: #555555;
}

.site-header h1 {
  font-size: 22px;
  color: #79a6e0;
  text-align: center;
  margin: 0 0 30px 0;
  text-shadow: 1px 1px #000;
}

h2 {
  margin-bottom: 20px;
  color: #e0e0e0;
  text-decoration: underline;
}

.back-btn {
  display: inline-block;
  padding: 8px 16px;
  background: #3a3a3a;
  color: #ffffff;
  text-decoration: none;
  border: 2px solid #555555;
  font-size: 14px;
  cursor: pointer;
}

.back-btn:hover {
  background: #4a4a4a;
}

/* 卡片布局 */
.resource-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
  margin-bottom: 30px;
}

.resource-card {
  background: #3a3a3a;
  border: 2px solid #555555;
  box-shadow: inset -2px -2px #444444, inset 2px 2px #000000;
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease;
}

.resource-card:hover {
  transform: translateY(-3px);
}

.card-header {
  padding: 15px;
  border-bottom: 1px solid #555555;
}

.card-header h3 {
  margin: 0 0 8px 0;
  color: #79a6e0;
  font-size: 18px;
}

.card-category {
  display: inline-block;
  padding: 3px 8px;
  background: #0066cc;
  color: #ffffff;
  border-radius: 3px;
  font-size: 11px;
}

.card-body {
  padding: 15px;
  flex: 1;
}

.card-body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.4;
  color: #cccccc;
}

.card-footer {
  padding: 12px 15px;
  border-top: 1px solid #555555;
  display: flex;
  justify-content: flex-end;
}

.download-btn {
  padding: 8px 20px;
  background: #0066cc;
  color: #ffffff;
  text-decoration: none;
  border: 2px solid #0077ee;
  font-size: 14px;
  font-weight: bold;
  cursor: pointer;
  transition: all 0.2s ease;
}

.download-btn:hover {
  background: #0077dd;
  border-color: #0088ff;
}

.download-btn:active {
  background: #0055bb;
  transform: translateY(1px);
  border-color: #ffffff;
  animation: flash-border 0.6s ease;
}

@keyframes flash-border {
  0%   { border-color: #ffffff; }
  50%  { border-color: #ffcc00; }
  100% { border-color: #0077ee; }
}