:root {
    --primary: #0F172A;
    --accent: #2563EB;
    --accent-hover: #1D4ED8;
    --bg: #F8FAFC;
    --card: #FFFFFF;
    --text: #1E293B;
    --text-muted: #64748B;
    --border: #E2E8F0;
    --success: #16A34A;
    --danger: #DC2626;
    --radius: 8px;
}

* { box-sizing: border-box; margin: 0; padding: 0; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
body { background-color: var(--bg); color: var(--text); line-height: 1.5; min-height: 100vh; display: flex; flex-direction: column; }
header { background: var(--primary); color: white; padding: 1rem 2rem; display: flex; justify-content: space-between; align-items: center; }
header a { color: white; text-decoration: none; font-weight: 600; }
.logo { font-size: 1.5rem; font-weight: bold; color: white; text-decoration: none; }
nav a { margin-left: 1.5rem; }
.cart-badge { background: var(--accent); padding: 0.2rem 0.6rem; border-radius: 12px; font-size: 0.8rem; }
main { flex: 1; max-width: 1200px; width: 100%; margin: 2rem auto; padding: 0 1rem; }
.hero { background: linear-gradient(135deg, #1E293B 0%, #0F172A 100%); color: white; border-radius: var(--radius); padding: 3rem 2rem; margin-bottom: 2rem; text-align: center; }
.hero h1 { font-size: 2.5rem; margin-bottom: 0.5rem; }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1.5rem; }
.card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; display: flex; flex-direction: column; }
.card img { width: 100%; height: 220px; object-fit: cover; }
.card-body { padding: 1.25rem; flex: 1; display: flex; flex-direction: column; }
.card-title { font-size: 1.1rem; margin-bottom: 0.5rem; color: var(--primary); }
.card-text { font-size: 0.9rem; color: var(--text-muted); margin-bottom: 1rem; flex: 1; }
.card-price { font-size: 1.25rem; font-weight: bold; color: var(--primary); margin-bottom: 1rem; }
.btn { background: var(--accent); color: white; border: none; padding: 0.75rem 1rem; border-radius: var(--radius); cursor: pointer; text-decoration: none; text-align: center; font-weight: 600; display: inline-block; width: 100%; }
.btn:hover { background: var(--accent-hover); }
.btn-danger { background: var(--danger); }
.btn-secondary { background: var(--text-muted); }
footer { background: var(--primary); color: var(--text-muted); text-align: center; padding: 1.5rem; margin-top: auto; font-size: 0.9rem; }
table { width: 100%; border-collapse: collapse; margin-bottom: 1.5rem; background: var(--card); border-radius: var(--radius); overflow: hidden; }
th, td { padding: 1rem; text-align: left; border-bottom: 1px solid var(--border); }
th { background: #F1F5F9; font-weight: 600; }
.form-group { margin-bottom: 1.25rem; }
.form-group label { display: block; margin-bottom: 0.5rem; font-weight: 600; }
.form-control { width: 100%; padding: 0.75rem; border: 1px solid var(--border); border-radius: var(--radius); font-size: 1rem; }
.alert { padding: 1rem; border-radius: var(--radius); margin-bottom: 1rem; }
.alert-error { background: #FEE2E2; color: #991B1B; border: 1px solid #FCA5A5; }
.alert-success { background: #DCFCE7; color: #166534; border: 1px solid #86EFAC; }
.qr-container { text-align: center; background: white; padding: 2rem; border-radius: var(--radius); border: 1px solid var(--border); max-width: 400px; margin: 0 auto; }
.qr-container img { max-width: 250px; width: 100%; height: auto; }
.copia-cola { font-family: monospace; font-size: 0.8rem; word-break: break-all; background: #F1F5F9; padding: 0.5rem; border-radius: 4px; margin: 1rem 0; max-height: 80px; overflow-y: auto; }
@media (max-width: 768px) {
    header { flex-direction: column; gap: 1rem; text-align: center; }
    nav a { margin: 0 0.5rem; }
    .hero h1 { font-size: 1.75rem; }
}