:root {
  --pay-bg: #eef1f5;
  --pay-card: #ffffff;
  --pay-navy: #1c4268;
  --pay-navy-dark: #15324f;
  --pay-text: #2d3748;
  --pay-muted: #718096;
  --pay-border: #dde3ea;
  --pay-info-bg: #e8f0f7;
  --pay-danger: #e53935;
  --pay-radius: 6px;
  --pay-shadow: 0 8px 32px rgba(28, 66, 104, .08);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body.pay-ui {
  min-height: 100vh;
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: var(--pay-bg);
  color: var(--pay-text);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.25rem;
}

.pay-wrap {
  width: 100%;
  max-width: 720px;
}

.pay-card {
  background: var(--pay-card);
  border-radius: var(--pay-radius);
  box-shadow: var(--pay-shadow);
  overflow: hidden;
}

.pay-head {
  padding: 1.75rem 1.5rem 1.25rem;
  text-align: center;
}

.pay-badge {
  display: inline-block;
  background: var(--pay-navy);
  color: #fff;
  font-weight: 700;
  font-size: 1.35rem;
  letter-spacing: .04em;
  padding: .55rem 2rem;
  border-radius: 999px;
  min-width: 180px;
}

.pay-tabs {
  display: flex;
  justify-content: center;
  gap: .5rem;
  margin-top: 1rem;
}

.pay-tab {
  border: 1px solid var(--pay-border);
  background: #fff;
  color: var(--pay-muted);
  padding: .45rem 1.1rem;
  border-radius: 999px;
  font-size: .85rem;
  font-weight: 600;
  cursor: pointer;
}

.pay-tab.active {
  background: var(--pay-navy);
  border-color: var(--pay-navy);
  color: #fff;
}

.pay-sub {
  margin-top: 1rem;
  color: var(--pay-muted);
  font-size: .95rem;
}

.pay-body { padding: 0 1.5rem 1.5rem; }

.pay-grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1rem;
}

.pay-field label {
  display: block;
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--pay-muted);
  margin-bottom: .4rem;
  text-transform: uppercase;
}

.pay-field input,
.pay-field textarea {
  width: 100%;
  border: 1px solid var(--pay-border);
  border-radius: var(--pay-radius);
  padding: .85rem .9rem;
  font-size: .95rem;
  color: var(--pay-text);
  background: #fff;
}

.pay-field input:focus,
.pay-field textarea:focus {
  outline: none;
  border-color: var(--pay-navy);
}

.pay-field input[readonly] {
  background: #f8fafc;
}

.pay-amount-wrap { position: relative; margin-bottom: 1rem; }

.pay-amount-wrap input { padding-right: 2.5rem; text-align: right; }

.pay-amount-suffix {
  position: absolute;
  right: .9rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--pay-muted);
  font-weight: 600;
}

.pay-actions {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin: 1.25rem 0;
}

.pay-btn {
  border: none;
  border-radius: var(--pay-radius);
  padding: .75rem 1.5rem;
  font-size: .9rem;
  font-weight: 700;
  letter-spacing: .03em;
  cursor: pointer;
  min-width: 130px;
}

.pay-btn-cancel {
  background: #fff;
  border: 1px solid var(--pay-danger);
  color: var(--pay-danger);
}

.pay-btn-primary {
  background: var(--pay-navy);
  color: #fff;
}

.pay-btn-primary:hover { background: var(--pay-navy-dark); }

.pay-btn-block {
  width: 100%;
  padding: 1rem;
  font-size: 1rem;
  margin-top: .5rem;
}

.pay-btn:disabled { opacity: .55; cursor: not-allowed; }

.pay-info {
  background: var(--pay-info-bg);
  border-left: 4px solid var(--pay-navy);
  padding: 1rem 1.1rem;
  font-size: .88rem;
  line-height: 1.55;
  color: #4a5568;
}

.pay-info b.red { color: var(--pay-danger); font-weight: 700; }

.pay-info ul { padding-left: 1.1rem; }
.pay-info li { margin-bottom: .35rem; }

.pay-status {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  background: #f4f7fa;
  border: 1px solid var(--pay-border);
  border-radius: var(--pay-radius);
  padding: 1rem;
  margin-bottom: 1rem;
}

.pay-status .label {
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .05em;
  color: var(--pay-muted);
  text-transform: uppercase;
}

.pay-status .value {
  font-size: 1.35rem;
  font-weight: 700;
  margin-top: .25rem;
}

.pay-status .timer .value { color: var(--pay-danger); }

.pay-copy-row {
  display: flex;
  gap: .5rem;
  align-items: stretch;
}

.pay-copy-row input { flex: 1; }

.pay-copy-btn {
  width: 46px;
  min-width: 46px;
  border: none;
  border-radius: var(--pay-radius);
  background: var(--pay-navy);
  color: #fff;
  cursor: pointer;
  font-size: 1rem;
}

.pay-copy-btn:hover { background: var(--pay-navy-dark); }

.pay-step { display: none; }
.pay-step.active { display: block; }

.pay-coins { display: flex; flex-direction: column; gap: .65rem; margin: 1rem 0; }

.pay-coin-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  margin: 0 0 1rem;
}

.pay-coin-tab {
  border: 1px solid var(--pay-border);
  background: #fff;
  color: var(--pay-navy);
  border-radius: 999px;
  padding: .55rem 1rem;
  font-weight: 700;
  font-size: .85rem;
  cursor: pointer;
  transition: background .15s, border-color .15s, color .15s;
}

.pay-coin-tab.active {
  background: var(--pay-navy);
  border-color: var(--pay-navy);
  color: #fff;
}

.pay-coin-detail {
  border: 1px solid var(--pay-border);
  border-radius: var(--pay-radius);
  padding: 1rem;
  background: rgba(28, 66, 104, .03);
}

.pay-coin-detail.hidden { display: none; }

.pay-coin-detail-head { margin-bottom: .75rem; }

.pay-coin-detail .pay-qr-main {
  margin: 0 0 1rem;
  padding: .75rem;
}

.pay-coin-detail .pay-copy-row { margin-top: 0; }

.pay-coin {
  border: 1px solid var(--pay-border);
  border-radius: var(--pay-radius);
  padding: .85rem;
  cursor: pointer;
  transition: border-color .15s, background .15s;
}

.pay-coin.active {
  border-color: var(--pay-navy);
  background: rgba(28, 66, 104, .05);
}

.pay-coin-title { font-weight: 700; font-size: .95rem; }
.pay-coin-sub { font-size: .78rem; color: var(--pay-muted); margin-top: .15rem; }

.pay-coin .pay-copy-row { margin-top: .65rem; }

.pay-qr-wrap {
  display: flex;
  justify-content: center;
  margin: .85rem 0 .25rem;
  padding: .65rem;
  background: #fff;
  border: 1px dashed var(--pay-border);
  border-radius: var(--pay-radius);
}

.pay-qr-wrap img {
  width: 180px;
  height: 180px;
  image-rendering: pixelated;
}

.pay-qr-main {
  text-align: center;
  margin: 1rem 0;
  padding: 1rem;
  background: #fff;
  border: 1px solid var(--pay-border);
  border-radius: var(--pay-radius);
}

.pay-qr-main img {
  width: 200px;
  height: 200px;
}

.pay-qr-hint {
  margin-top: .5rem;
  font-size: .82rem;
  color: var(--pay-muted);
}

.pay-coin .pay-qr-wrap { display: none; }
.pay-coin.active .pay-qr-wrap { display: none; }

.pay-error {
  background: #fef2f2;
  border: 1px solid #fecaca;
  color: #b91c1c;
  padding: .75rem;
  border-radius: var(--pay-radius);
  font-size: .875rem;
  margin-bottom: 1rem;
}

.pay-success {
  text-align: center;
  padding: 1.5rem 1rem 2rem;
}

.pay-success-icon {
  width: 72px;
  height: 72px;
  margin: 1.25rem auto 1.5rem;
  border-radius: 50%;
  background: #22c55e;
  color: #fff;
  font-size: 2rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 14px rgba(34, 197, 94, .35);
}

.pay-success h2 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: .75rem;
  color: var(--pay-text);
}

.pay-success p {
  font-size: .95rem;
  color: #4a5568;
  line-height: 1.5;
  margin-bottom: .5rem;
}

.pay-success .pay-success-note {
  color: var(--pay-danger);
  font-weight: 600;
  margin: 1rem 0 1.75rem;
}

.pay-head.compact .pay-tabs,
.pay-head.compact .pay-sub { display: none; }

.hidden { display: none !important; }

@media (max-width: 640px) {
  .pay-grid-2 { grid-template-columns: 1fr; }
  .pay-actions { flex-direction: column-reverse; }
  .pay-btn { width: 100%; }
  .pay-status { grid-template-columns: 1fr; }
}