:root {
  --bg: #f5f7fb;
  --card: #ffffff;
  --primary: #3b6cff;
  --text: #1d2433;
  --muted: #8a93a6;
  --border: #e4e8f0;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, "PingFang SC", "Microsoft YaHei", Segoe UI, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 28px;
  background: var(--card);
  border-bottom: 1px solid var(--border);
}
.brand { font-weight: 700; font-size: 18px; color: var(--text); text-decoration: none; }
.topnav { display: flex; gap: 10px; align-items: center; }
.ghost-btn {
  background: transparent; color: var(--text); border: 1px solid var(--border);
  padding: 8px 14px; border-radius: 10px; cursor: pointer; text-decoration: none; font-size: 14px;
}
.ghost-btn:hover { border-color: var(--primary); color: var(--primary); }

.hero { text-align: center; padding: 56px 20px 8px; }
.hero h1 { font-size: 34px; margin: 0 0 10px; }
.hero p { color: var(--muted); margin: 0; }

.grid {
  max-width: 1180px;
  margin: 0 auto;
  padding: 28px 20px 64px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
@media (max-width: 1000px) { .grid { grid-template-columns: repeat(3, 1fr); } }
@media (max-width: 680px)  { .grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 430px)  { .grid { grid-template-columns: 1fr; } }

.card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 20px;
  text-decoration: none;
  color: inherit;
  transition: transform .15s, box-shadow .15s, border-color .15s;
}
.card:not(.disabled):hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 28px rgba(59, 108, 255, .12);
  border-color: var(--primary);
}
.card.disabled { opacity: .6; }
.card-icon { font-size: 34px; margin-bottom: 12px; }
.card h3 { margin: 0 0 8px; font-size: 18px; }
.card p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.6; }

.tag {
  display: inline-block;
  margin-top: 14px;
  font-size: 12px;
  padding: 3px 10px;
  border-radius: 999px;
  background: #eef1f6;
  color: var(--muted);
}
.tag-live { background: #e6f7ee; color: #1a9d5a; }

.footer { text-align: center; color: var(--muted); font-size: 13px; padding: 24px; }