body { font-family: system-ui, sans-serif; background: #f4f5f7; margin: 0; display: grid; min-height: 100vh; place-items: center; }
.cartao { background: #fff; padding: 2rem; border-radius: 12px; box-shadow: 0 2px 12px rgba(0,0,0,.1); max-width: 26rem; width: 90%; }
.botao { display: block; text-align: center; margin: .6rem 0; padding: .7rem 1rem; border: 0; border-radius: 8px; background: #1f2937; color: #fff; text-decoration: none; font-size: 1rem; cursor: pointer; width: 100%; box-sizing: border-box; }
.botao:hover { background: #374151; }