.rrtb-grid{
display:grid;
grid-template-columns:repeat(auto-fit,minmax(300px,1fr));
gap:16px;
}
.rrtb-card{
background:#fff;
border:1px solid #ddd;
border-radius:8px;
padding:16px;
}
.rrtb-card h3{
margin-top:0;
font-size:20px;
}