:root{
  --bg:#f4f6fb;
  --card:#fff;
  --primary:#111827;
  --accent:#3b82f6;
  --danger:#ef4444;

  --text:#111827;
  --muted:#6b7280;

  --radius:14px;
  --shadow:0 10px 30px rgba(0,0,0,.08);
}

*{box-sizing:border-box}
body{
  margin:0;
  font-family:system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif;
  background:var(--bg);
  color:var(--text);
}
a{color:var(--accent);text-decoration:none}

.container{max-width:980px;margin:0 auto;padding:40px 20px}
.card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);padding:24px}

h1,h2,h3{margin:0 0 10px}
.muted{color:var(--muted);font-size:14px}

input{
  width:100%;
  padding:12px 14px;
  border-radius:10px;
  border:1px solid #d1d5db;
  font-size:15px;
}
input:focus{outline:none;border-color:var(--accent)}

button{
  width:100%;
  padding:12px;
  border:none;
  border-radius:10px;
  background:var(--primary);
  color:#fff;
  font-size:15px;
  cursor:pointer;
}
button:hover{opacity:.9}

.form-group{margin-bottom:14px}
.error{margin-top:12px;color:var(--danger);font-size:14px}

/* Small UI primitives */
.topbar{
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:12px;
  flex-wrap:wrap;
  margin-bottom:20px;
}

.badge{
  display:inline-block;
  padding:4px 10px;
  border-radius:999px;
  font-size:12px;
  background:#e5e7eb;
}
.badge.admin{background:#fee2e2;color:#991b1b}
.badge.user{background:#e0e7ff;color:#1e3a8a}

.btn{
  display:inline-block;
  padding:8px 14px;
  border-radius:10px;
  background:var(--primary);
  color:#fff;
}
.btn.logout{background:#374151}

hr.sep{border:none;border-top:1px solid #e5e7eb;margin:20px 0}

.kb-booklink {
  display: flex;
  gap: 10px;
  text-decoration: none;
  color: inherit;
}

.kb-booklink:hover .kb-titlecell {
  text-decoration: underline;
}

.kb-bookcell {
  align-items: flex-start;
}