:root {
  --fg: #1f2937;
  --muted: #6b7280;
  --bg: #f9fafb;
  --card: #ffffff;
  --border: #e5e7eb;
  --primary: #3370ff;
  --primary-hover: #245bdc;
  --success: #10b981;
  --warn: #f59e0b;
  --danger: #ef4444;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, "Helvetica Neue", "PingFang SC", Arial, sans-serif;
  color: var(--fg);
  background: var(--bg);
  font-size: 14px;
  line-height: 1.6;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 24px;
  background: var(--card);
  border-bottom: 1px solid var(--border);
}

.brand {
  font-weight: 600;
  color: var(--fg);
  text-decoration: none;
}

.topbar nav { display: flex; gap: 16px; align-items: center; }
.topbar nav a { color: var(--muted); text-decoration: none; }
.topbar nav a:hover { color: var(--fg); }
.topbar .user { color: var(--fg); font-weight: 500; }

main { max-width: 960px; margin: 32px auto; padding: 0 24px; }

footer {
  text-align: center;
  padding: 24px;
  color: var(--muted);
  font-size: 12px;
}

.hero {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 48px;
  text-align: center;
}
.hero h1 { margin: 0 0 12px; }
.hero .lede { color: var(--muted); margin-bottom: 24px; }
.hint { color: var(--muted); font-size: 12px; margin-top: 16px; }

.btn-primary {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  padding: 10px 24px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 500;
  border: none;
  cursor: pointer;
  font-size: 14px;
}
.btn-primary:hover { background: var(--primary-hover); }
.btn-primary:disabled { background: var(--muted); cursor: not-allowed; }