body {
  background: linear-gradient(135deg, #eef3fe 0%, #f4f7ff 40%, #e8f0fe 100%);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 80px var(--sp-4) var(--sp-8);
  position: relative;
}
html, body { height:100% }

/* ===================================================
   卡片
   =================================================== */
.card {
  background: #fff;
  border-radius: var(--r-xl);
  box-shadow: 0 12px 48px rgba(0,0,0,.12), 0 2px 8px rgba(21,78,209,.10);
  width: 100%;
  max-width: 480px;
  padding: var(--sp-8);
  margin: auto;
  position: relative;
  z-index: 1;
  animation: fadeUp .5s var(--ease-out-quart) both;
}

@keyframes fadeUp {
  from { opacity:0; transform:translateY(24px) }
  to   { opacity:1; transform:translateY(0) }
}

/* Logo */
.card__logo {
  display: flex;
  justify-content: center;
  margin-bottom: var(--sp-6);
}
.card__logo img {
  height: 80px;
  width: auto;
  object-fit: contain;
}

/* 标题区 */
.card__title {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--gray-900);
  text-align: center;
  margin-bottom: var(--sp-2);
  letter-spacing: -0.02em;
}
.card__subtitle {
  font-size: var(--text-sm);
  color: var(--gray-500);
  text-align: center;
  margin-bottom: var(--sp-6);
  line-height: 1.5;
}

/* 分割线 */
.card__divider {
  height: 1px;
  background: var(--gray-100);
  margin-bottom: var(--sp-6);
}

/* ===================================================
   二维码展示区
   =================================================== */
.qr-wrapper {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: var(--sp-5);
}
.qr-frame {
  width: 220px;
  height: 220px;
  border-radius: var(--r-lg);
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(0,0,0,.08);
  border: 2px solid var(--gray-100);
  margin-bottom: var(--sp-4);
}
.qr-frame img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}
.qr-hint {
  font-size: var(--text-sm);
  color: var(--gray-500);
  text-align: center;
  line-height: 1.6;
}

/* ===================================================
   底部返回
   =================================================== */
.card__back {
  text-align: center;
  margin-top: var(--sp-5);
  font-size: var(--text-sm);
  color: var(--gray-500);
}
.card__back a {
  color: var(--blue-600);
  text-decoration: none;
  font-weight: 600;
}
.card__back a:hover { text-decoration: underline }

/* ===================================================
   响应式
   =================================================== */
@media (max-width: 768px) {
  body { padding: 72px var(--sp-4) var(--sp-6) }
}
@media (max-width: 520px) {
  .card { padding: var(--sp-6) var(--sp-5) }
  .card__title { font-size: var(--text-xl) }
}