:root {
  --page-bg: #ffffff;
  --text: #1f2329;
  --muted: #b5b8c0;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  background: var(--page-bg);
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

body {
  min-height: 100vh;
}

.page-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 20px;
}

.poster-wrap {
  width: min(100%, 560px);
  margin: 0 auto;
}

.poster-image {
  display: block;
  width: 100%;
  height: auto;
  background: #fff;
}

.fallback-card {
  display: none;
  text-align: center;
  padding: 32px 24px;
  border: 1px solid #eceef2;
  border-radius: 18px;
  background: #fff;
  box-shadow: 0 14px 40px rgba(17, 24, 39, 0.06);
}

.fallback-card.is-visible {
  display: block;
}

.fallback-title {
  margin: 0 0 10px;
  color: var(--text);
  font-size: 26px;
  font-weight: 700;
}

.fallback-text {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.7;
}

@media (max-width: 640px) {
  .page-shell {
    padding: 10px;
  }

  .poster-wrap {
    width: min(100%, 520px);
  }
}