:root {
  --accent:#0b63f6;
  --bg:#ffffff;
  --muted:#6b7280;
  --radius:12px;
}

*{box-sizing:border-box}
html,body{height:100%;margin:0}
body{
  font-family:Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial;
  background:#f3f4f6;
  color:#111827;
}

.container{
  display:flex;
  align-items:center;
  justify-content:center;
  min-height:100vh;
  padding:28px;
}

.card{
  width:100%;
  max-width:760px;
  background:var(--bg);
  border-radius:var(--radius);
  box-shadow:0 10px 30px rgba(2,6,23,0.08);
  padding:26px;
}

.title{margin:0 0 6px;font-size:22px}
.subtitle{color:var(--muted);margin:0 0 18px;font-size:14px}

label{display:block;margin-top:12px;font-weight:600;font-size:13px}
select,input{width:100%;padding:12px;border:1px solid #e6e6e9;border-radius:10px;font-size:14px;margin-top:6px}
.row{display:flex;gap:12px;margin-top:12px}
.col{flex:1}
.amount{font-weight:800;font-size:18px;padding:12px;border-radius:10px;background:#f8fafc;border:1px solid #edf2f7;text-align:left}

.tabs{display:flex;gap:8px;margin-top:16px}
.tab{flex:1;padding:10px;border-radius:10px;border:1px solid #e6e6e9;background:#fff;cursor:pointer;text-align:center}
.tab.active{background:var(--accent);color:#fff;border-color:transparent}

.tabcontent{display:none;margin-top:12px}
.tabcontent.active{display:block}

.btn{margin-top:18px;background:var(--accent);color:#fff;border:none;padding:12px;border-radius:10px;font-weight:700;width:100%;cursor:pointer}
.note{color:var(--muted);font-size:13px;margin-top:12px}
.help{color:var(--muted);font-size:13px;margin-top:8px}
.small{font-size:13px;color:var(--muted)}

.modal{display:none;position:fixed;inset:0;align-items:center;justify-content:center;background:rgba(0,0,0,0.45);z-index:9999}
.modal-inner{background:#fff;padding:22px;border-radius:12px;min-width:320px;text-align:center}
.modal h2{margin:0 0 6px}
.modal p{margin:6px 0}
.whatsapp{display:inline-block;margin-top:8px;background:#25D366;color:#fff;padding:10px 14px;border-radius:10px;text-decoration:none;font-weight:700}
.closeBtn{display:block;margin:12px auto 0;padding:8px 14px;border-radius:8px;border:0;background:#0b63f6;color:#fff;cursor:pointer}

/* Mobile: full width */
@media (max-width:720px){
  .container{padding:0}
  .card{border-radius:0;max-width:100%;min-height:100vh;padding:18px}
  body{background:#fff}
  .row{flex-direction:column}
}