/* ============================================================
   pages/course.html 样式（v2：play.html 同源设计语言）
   ============================================================ */
:root {
  /* —— 与 play.html 完全一致 —— */
  --bg-page:        #fbfbfd;
  --bg-card:        #ffffff;
  --text-primary:   #1d1d1f;
  --text-secondary: #424245;
  --text-muted:     #6e6e73;
  --text-hint:      #86868b;
  --border:         rgba(0,0,0,0.08);
  --border-soft:    rgba(0,0,0,0.04);
  --accent:         #0a84ff;
  --accent-soft:    rgba(10,132,255,0.12);

  /* —— 阴影 / 圆角（与 play.html 一致） —— */
  --shadow-card:    0 1px 2px rgba(0,0,0,0.04), 0 6px 18px rgba(0,0,0,0.04);
  --shadow-hover:   0 1px 2px rgba(0,0,0,0.04), 0 12px 32px rgba(0,0,0,0.08);
  --shadow-banner:  0 1px 2px rgba(0,0,0,0.04), 0 12px 40px rgba(0,0,0,0.06), 0 0 0 1px rgba(0,0,0,0.02);

  --radius-card:        20px;
  --radius-banner:      28px;
  --radius-icon-card:   18px;
  --radius-icon-banner: 48px;
}

body {
  /* 浅色 radial-gradient：让顶部导航栏背后有色彩，凸显 Glassmorphism */
  background:
    radial-gradient(ellipse 90% 50% at 50% 0%, rgba(10, 132, 255, 0.14) 0%, transparent 55%),
    radial-gradient(ellipse 60% 40% at 0% 40%, rgba(175, 82, 222, 0.08) 0%, transparent 55%),
    radial-gradient(ellipse 60% 40% at 100% 70%, rgba(255, 45, 85, 0.06) 0%, transparent 55%),
    var(--bg-page);
  background-attachment: fixed;
}

/* 主区（顶栏由 topbar.js 统一注入） */
main {
  max-width: 1280px;
  margin: 0 auto;
  padding: 32px 40px 80px;
}

.footer {
  max-width: 1280px;
  margin: 0 auto;
  padding: 24px 40px;
  display: flex; justify-content: space-between; align-items: center;
  color: var(--text-hint);
  font-family: -apple-system, BlinkMacSystemFont, "Inter", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  font-size: 12px;
  font-weight: 500;
  border-top: 1px solid #f2f2f4;
}
.footer .build { letter-spacing: 0.16em; text-transform: uppercase; }
.footer .live::before {
  content: '';
  display: inline-block;
  width: 6px; height: 6px;
  background: #10b981;
  border-radius: 50%;
  margin-right: 6px;
  vertical-align: middle;
}

@media (max-width: 720px) {
  .footer { padding: 20px 24px; gap: 12px; }
  main { padding: 24px 20px 60px; }
}