/* 新增优化样式 */
.hero {
  position: relative;
  padding: 60px 0;
  background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
  margin-bottom: 40px;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, #4285f4, #34a853, #fbbc05, #ea4335);
}

.hero h1 {
  color: #ffffff;
  /* 白色标题 */
}

.hero .hero-sub {
  color: rgba(255, 255, 255, 0.9);
  /* 半透明白色副标题 */
}

.center-card {
  max-width: 800px;
  margin: 0 auto 60px;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  overflow: hidden;
  transition: transform 0.3s ease;
}

.center-card:hover {
  transform: translateY(-5px);
}

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  background: #f8f9fa;
  padding: 40px;
}

.card-body {
  padding: 30px;
}

.card-title {
  font-size: 24px;
  margin-bottom: 15px;
  color: #202124;
  display: flex;
  align-items: center;
}

.card-title::before {
  content: "📁";
  margin-right: 10px;
  font-size: 28px;
}

.card-desc {
  font-size: 16px;
  line-height: 1.6;
  color: #5f6368;
  margin-bottom: 25px;
  padding-left: 5px;
  border-left: 3px solid #4285f4;
}

.card-desc strong {
  color: #202124;
}

.actions {
  display: flex;
  gap: 16px;
  margin-top: 20px;
}

.btn {
  padding: 12px 24px;
  border-radius: 6px;
  font-weight: 500;
  font-size: 15px;
  transition: all 0.2s ease;
  text-align: center;
}

.btn-primary {
  background: #4285f4;
  color: white;
  border: none;
}

.btn-primary:hover {
  background: #3367d6;
  box-shadow: 0 4px 8px rgba(66, 133, 244, 0.3);
}

.btn-secondary {
  background: white;
  color: #5f6368;
  border: 1px solid #dadce0;
}

.btn-secondary:hover {
  background: #f8f9fa;
  border-color: #c6c9cc;
}

.info-tips {
  background: #fef7e0;
  border-left: 4px solid #fbbc05;
  padding: 15px 20px;
  margin-top: 25px;
  border-radius: 0 4px 4px 0;
  display: flex;
  align-items: flex-start;
}

.info-tips::before {
  content: "💡";
  margin-right: 10px;
  font-size: 20px;
  flex-shrink: 0;
  margin-top: -2px;
}

.info-tips p {
  margin: 0;
  color: #5f6368;
  font-size: 14px;
}

.resource-types {
  margin-top: 40px;
  padding-top: 30px;
  border-top: 1px solid #eee;
}

.resource-title {
  font-size: 18px;
  margin-bottom: 20px;
  color: #202124;
}

.resource-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 16px;
}

.resource-item {
  padding: 15px;
  border-radius: 8px;
  background: #f8f9fa;
  text-align: center;
  transition: all 0.2s ease;
}

.resource-item:hover {
  background: #f1f3f4;
  transform: scale(1.03);
}

.resource-icon {
  font-size: 24px;
  margin-bottom: 10px;
}

.resource-name {
  font-size: 14px;
  color: #5f6368;
}

@media (max-width: 768px) {
  .card-img {
    height: 150px;
    padding: 20px;
  }

  .card-body {
    padding: 20px;
  }

  .actions {
    flex-direction: column;
    gap: 10px;
  }

  .btn {
    width: 100%;
  }
}