:root {
  --bg: #f1f3f6;
  --bg-panel: #ffffff;
  --bg-soft: #f7f8fa;
  --border: rgba(40, 48, 60, 0.1);
  --text: #1a1f28;
  --text-muted: #6b7380;
  --brand: #4a5568;
  --brand-deep: #2d3748;
  --metal: #8b95a5;
  --brand-soft: rgba(74, 85, 104, 0.08);
  --usdt-green: #26a17b;
  --radius: 16px;
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font);
  color: var(--text);
  background:
    radial-gradient(ellipse 70% 40% at 50% -12%, rgba(74, 85, 104, 0.1), transparent 55%),
    linear-gradient(180deg, #f8f9fb 0%, var(--bg) 40%);
  display: flex;
  flex-direction: column;
}

.xb-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(12px);
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--border);
}

.xb-header-inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.xb-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.04em;
}

.xb-brand img {
  height: 40px;
  width: auto;
  max-width: 140px;
  object-fit: contain;
  border-radius: 8px;
}

.xb-badge {
  margin-left: auto;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--brand-deep);
  background: var(--brand-soft);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 999px;
}

.xb-main {
  flex: 1;
  width: 100%;
  max-width: 960px;
  margin: 0 auto;
  padding: 28px 16px 40px;
}

.xb-card {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 12px 36px rgba(26, 31, 40, 0.05);
  overflow: hidden;
  position: relative;
}

.xb-card::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--brand-deep), var(--metal), var(--brand-deep), transparent);
}

.xb-card-inner {
  display: grid;
  grid-template-columns: 1fr;
}

@media (min-width: 768px) {
  .xb-card-inner {
    grid-template-columns: 2fr 3fr;
  }
}

.xb-visual {
  padding: 36px 28px;
  text-align: center;
  background:
    linear-gradient(180deg, rgba(74, 85, 104, 0.06), transparent 70%),
    var(--bg-soft);
  border-bottom: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
}

@media (min-width: 768px) {
  .xb-visual {
    border-bottom: none;
    border-right: 1px solid var(--border);
    padding: 48px 32px;
  }
}

.xb-visual .cover {
  width: min(78%, 240px);
  height: auto;
  object-fit: contain;
  border-radius: 14px;
  background: #2a2f38;
  border: 1px solid var(--border);
  box-shadow: 0 10px 28px rgba(26, 31, 40, 0.12);
}

.commodity_name {
  margin: 0;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.45;
}

.xb-visual .commodity_name {
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 500;
  max-width: 260px;
}

.xb-form-wrap {
  padding: 28px 24px 32px;
}

@media (min-width: 768px) {
  .xb-form-wrap { padding: 36px 36px 40px; }
}

.xb-form-title {
  margin: 0 0 6px;
  font-size: 1.25rem;
  font-weight: 700;
}

.xb-form-sub {
  margin: 0 0 20px;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.xb-meta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
  padding: 8px 12px;
  font-size: 0.82rem;
  color: var(--text-muted);
  background: #eef0f3;
  border: 1px solid var(--border);
  border-radius: 999px;
}

.xb-meta .delivery_way {
  color: var(--brand-deep);
  font-weight: 600;
}

.xb-field { margin-bottom: 16px; }

.xb-field label,
.form-label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  text-transform: uppercase;
}

.form-control,
.form-select {
  width: 100%;
  max-width: none;
  background: #fff !important;
  border: 1px solid #e2e5ea !important;
  color: var(--text) !important;
  border-radius: 10px !important;
  padding: 12px 14px !important;
  font-size: 0.95rem !important;
  box-shadow: none !important;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.form-control::placeholder { color: #9aa3b0; }

.form-control:focus,
.form-select:focus {
  border-color: var(--brand) !important;
  box-shadow: 0 0 0 3px var(--brand-soft) !important;
  outline: none;
}

.form-control.is-invalid {
  border-color: #e05353 !important;
}

.form-select option {
  background: #fff;
  color: var(--text);
}

.xb-amount {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 16px;
  margin-bottom: 12px;
  border-radius: 10px;
  background: #f4f5f7;
  border: 1px solid #e2e5ea;
}

.xb-amount-label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.trade_amount {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--brand-deep);
  font-variant-numeric: tabular-nums;
}

#stockInfo {
  display: block;
  margin-bottom: 16px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

#stockInfo .card_count {
  color: var(--text);
  font-weight: 600;
}

.pay-content { padding-bottom: 0; }
.pay_title { display: none; }

#usdtButton {
  width: 100%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 20px;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: #fff !important;
  background: linear-gradient(135deg, var(--usdt-green), #1e8a68) !important;
  border: none !important;
  border-radius: 10px !important;
  box-shadow: 0 8px 20px rgba(38, 161, 123, 0.25);
  transition: transform 0.15s, box-shadow 0.15s, filter 0.15s;
  cursor: pointer;
}

#usdtButton:hover {
  filter: brightness(1.05);
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(38, 161, 123, 0.35);
}

#usdtButton:active { transform: translateY(0); }
#usdtButton img { height: 26px; width: auto; }

.xb-rules {
  margin-top: 24px;
  padding: 18px 20px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 4px 16px rgba(26, 31, 40, 0.04);
}

.description-title {
  margin: 0 0 10px;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--brand-deep);
  text-transform: uppercase;
}

.product-description {
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--text-muted);
}

.footer {
  padding: 18px 16px 28px;
  border-top: 1px solid var(--border);
  background: #fff;
}

.footer p {
  margin: 0;
  font-size: 0.8rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
}

.navbar-toggler { display: none; }

.xb-toast {
  position: fixed;
  left: 50%;
  bottom: 28px;
  transform: translateX(-50%) translateY(12px);
  z-index: 50;
  max-width: min(90vw, 420px);
  padding: 12px 16px;
  border-radius: 10px;
  font-size: 0.9rem;
  line-height: 1.45;
  color: #fff;
  background: #2d3748;
  box-shadow: 0 10px 28px rgba(26, 31, 40, 0.2);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s, transform 0.2s;
}

.xb-toast.is-show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.xb-toast.is-ok { background: #1e8a68; }
.xb-toast.is-err { background: #c44545; }