/* ========== 首页专用样式 ========== */

/* 英雄区 */
.hero {
  background: linear-gradient(135deg, #0F172A 0%, #1E3A5F 50%, #1E40AF 100%);
  padding: 88px 24px 80px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%; left: -50%;
  width: 200%; height: 200%;
  background: radial-gradient(circle at 30% 40%, rgba(37,99,235,0.3) 0%, transparent 50%),
              radial-gradient(circle at 70% 60%, rgba(14,165,233,0.2) 0%, transparent 50%);
  pointer-events: none;
}
.hero-grid {
  position: absolute;
  inset: 0;
  background-image: linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 40px 40px;
}
.hero-inner { position: relative; max-width: 760px; margin: 0 auto; }
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(37,99,235,0.3);
  border: 1px solid rgba(96,165,250,0.4);
  color: #93C5FD;
  padding: 5px 14px;
  border-radius: 100px;
  font-size: 13px;
  margin-bottom: 24px;
}
.hero-badge span { width: 6px; height: 6px; background: #60A5FA; border-radius: 50%; animation: pulse 2s infinite; }
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:0.4} }
.hero h1 { font-size: clamp(32px, 5vw, 52px); font-weight: 700; color: #fff; line-height: 1.2; margin-bottom: 20px; letter-spacing: -0.02em; }
.hero h1 em { font-style: normal; color: #60A5FA; }
.hero p { font-size: 17px; color: #94A3B8; max-width: 520px; margin: 0 auto 36px; line-height: 1.7; }
.hero-actions { display: flex; align-items: center; justify-content: center; gap: 14px; flex-wrap: wrap; }
.btn-hero-primary {
  padding: 13px 32px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.btn-hero-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(37,99,235,0.4); }
.btn-hero-outline {
  padding: 13px 32px;
  background: transparent;
  color: #E2E8F0;
  border: 1.5px solid rgba(226,232,240,0.3);
  border-radius: 10px;
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.btn-hero-outline:hover { border-color: rgba(226,232,240,0.7); background: rgba(255,255,255,0.05); }
.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  margin-top: 56px;
  padding-top: 40px;
  border-top: 1px solid rgba(255,255,255,0.08);
  flex-wrap: wrap;
}
.hero-stat { text-align: center; }
.hero-stat-num { font-size: 28px; font-weight: 700; color: #fff; }
.hero-stat-num span { color: #60A5FA; }
.hero-stat-label { font-size: 13px; color: #64748B; margin-top: 2px; }

/* 通用容器 */
.section { padding: 72px 24px; }
.container { max-width: 1200px; margin: 0 auto; }
.section-title { font-size: 30px; font-weight: 700; color: var(--text-main); margin-bottom: 8px; }
.section-sub { font-size: 15px; color: var(--text-sub); margin-bottom: 48px; }

/* 特色功能 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}
.feature-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  transition: all 0.25s;
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: #BFDBFE; }
.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  font-size: 22px;
}
/* 特色卡片图文并排 */
.feature-text { flex: 1; min-width: 0; }
.feature-img {
  flex-shrink: 0;
  width: 170px;
  border-radius: 10px;
  overflow: hidden;
}
.feature-img img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}
.feature-icon.blue { background: #EFF6FF; }
.feature-icon.green { background: #ECFDF5; }
.feature-icon.amber { background: #FFFBEB; }
.feature-icon.purple { background: #F5F3FF; }
.feature-icon.pink { background: #FDF2F8; }
.feature-icon.teal { background: #F0FDFA; }
.feature-card h3 { font-size: 16px; font-weight: 600; color: var(--text-main); margin-bottom: 8px; }
.feature-card p { font-size: 14px; color: var(--text-sub); line-height: 1.65; }

/* 课程模块 */
.courses-section { background: var(--white); }
.course-tabs { display: flex; gap: 8px; margin-bottom: 32px; flex-wrap: wrap; }
.course-tab {
  padding: 8px 20px;
  border: 1.5px solid var(--border);
  border-radius: 100px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-sub);
  cursor: pointer;
  background: transparent;
  transition: all 0.2s;
}
.course-tab.active, .course-tab:hover { background: var(--primary); color: #fff; border-color: var(--primary); }
.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.course-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all 0.25s;
  cursor: pointer;
}
.course-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.course-cover {
  height: 140px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 48px;
  position: relative;
}
.course-cover-1 { background: linear-gradient(135deg, #EFF6FF, #DBEAFE); }
.course-cover-2 { background: linear-gradient(135deg, #ECFDF5, #D1FAE5); }
.course-cover-3 { background: linear-gradient(135deg, #FFF7ED, #FED7AA); }
.course-cover-4 { background: linear-gradient(135deg, #F5F3FF, #EDE9FE); }
.course-cover-5 { background: linear-gradient(135deg, #FDF2F8, #FCE7F3); }
.course-cover-6 { background: linear-gradient(135deg, #ECFEFF, #CFFAFE); }
.course-body { padding: 16px 18px 20px; }
.course-category { font-size: 12px; color: var(--primary); font-weight: 500; margin-bottom: 6px; }
.course-title { font-size: 15px; font-weight: 600; color: var(--text-main); margin-bottom: 8px; line-height: 1.4; }
.course-desc { font-size: 13px; color: var(--text-sub); margin-bottom: 14px; line-height: 1.6; }
.course-meta { display: flex; align-items: center; justify-content: space-between; }
.course-info { display: flex; align-items: center; gap: 12px; font-size: 12px; color: var(--text-muted); }
.course-info span { display: flex; align-items: center; gap: 4px; }

/* 学习路径 */
.path-section { background: var(--primary-light); }
.path-timeline { position: relative; display: flex; flex-direction: column; gap: 0; }
.path-timeline::before {
  content: '';
  position: absolute;
  left: 27px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--primary), var(--accent), var(--success));
}
.path-item { display: flex; gap: 24px; padding: 0 0 36px; position: relative; }
.path-dot {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  font-weight: 700;
  color: #fff;
  flex-shrink: 0;
  position: relative;
  z-index: 1;
  border: 3px solid var(--primary-light);
}
.path-content {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  flex: 1;
  box-shadow: var(--shadow-sm);
}
.path-content h3 { font-size: 17px; font-weight: 600; color: var(--text-main); margin-bottom: 6px; }
.path-content p { font-size: 13px; color: var(--text-sub); margin-bottom: 12px; }
.path-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.path-tag {
  background: var(--primary-light);
  border: 1px solid #BFDBFE;
  color: var(--primary);
  font-size: 12px;
  padding: 3px 10px;
  border-radius: 100px;
}
.path-content h3 a { color: inherit; text-decoration: none; }
.path-content p a { color: inherit; text-decoration: none; }

/* 回到顶部 */
.back-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 44px;
  height: 44px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  box-shadow: 0 4px 16px rgba(37,99,235,0.4);
  transition: all 0.2s;
  opacity: 0;
  pointer-events: none;
}
.back-top.show { opacity: 1; pointer-events: auto; }
.back-top:hover { transform: translateY(-2px); background: var(--primary-dark); }

/* 首页响应式补充 */
@media(max-width: 768px){
  .hero { padding: 56px 20px 56px; }
  .hero-stats { gap: 20px; }
  .feature-card {
    gap: 12px !important;
    padding: 16px !important;
  }
  .feature-img {
    width: 95px !important;
  }
  .feature-icon {
    width: 38px;
    height: 38px;
    margin-bottom: 10px;
  }
  .feature-card h3 {
    font-size: 14px;
    margin-bottom: 4px;
  }
  .feature-card p {
    font-size: 12px;
    line-height: 1.5;
    margin-bottom: 2px;
  }
  }
}