* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: #f4f6f8;
  color: #18202a;
}
.page {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}
.card {
  width: min(720px, 100%);
  background: #fff;
  border: 1px solid #e2e7ec;
  border-radius: 18px;
  padding: 32px;
  box-shadow: 0 12px 35px rgba(0,0,0,.08);
}
.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 30px;
}
.logo {
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: #111827;
  color: white;
  font-size: 24px;
  font-weight: 700;
}
h1 { margin: 0; font-size: 26px; }
.subtitle { margin: 4px 0 0; color: #667085; }
label {
  display: block;
  font-weight: 700;
  margin-bottom: 8px;
}
.input-row {
  display: flex;
  gap: 10px;
}
input {
  flex: 1;
  min-width: 0;
  padding: 13px 14px;
  border: 1px solid #cfd6dd;
  border-radius: 9px;
  font-size: 16px;
  font-family: Consolas, monospace;
}
input:focus {
  outline: 2px solid #9ca3af;
  outline-offset: 1px;
}
button {
  border: 0;
  border-radius: 9px;
  padding: 13px 18px;
  background: #111827;
  color: white;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
}
button:disabled { opacity: .55; cursor: wait; }
.message { min-height: 22px; color: #b42318; margin: 12px 0; }
.result {
  margin-top: 12px;
  padding: 24px;
  border-radius: 12px;
  background: #f8fafc;
  border: 1px solid #e5e7eb;
}
.hidden { display: none; }
.result-label { color: #667085; font-size: 14px; }
.balance {
  margin: 5px 0;
  font-size: 38px;
  font-weight: 800;
}
.network { font-weight: 700; }
.wallet {
  margin-top: 10px;
  color: #667085;
  font-family: Consolas, monospace;
  overflow-wrap: anywhere;
}
.hint {
  margin: 24px 0 0;
  color: #667085;
  font-size: 13px;
  line-height: 1.5;
}
@media (max-width: 620px) {
  .card { padding: 22px; }
  .input-row { flex-direction: column; }
  button { width: 100%; }
  .balance { font-size: 31px; }
}