:root {
  color-scheme: light;
  --bg: #eef2f7;
  --panel: rgba(255, 255, 255, 0.9);
  --panel-border: rgba(15, 23, 42, 0.08);
  --text: #0f172a;
  --muted: #475569;
  --accent: #0f766e;
  --accent-strong: #115e59;
  --danger: #b91c1c;
  --shadow: 0 20px 60px rgba(15, 23, 42, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background:
    radial-gradient(circle at top, rgba(15, 118, 110, 0.12), transparent 32%),
    linear-gradient(180deg, #f6f8fb 0%, var(--bg) 100%);
  color: var(--text);
}

.shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 32px 20px;
}

.panel {
  width: min(640px, 100%);
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 28px;
  box-shadow: var(--shadow);
  padding: 36px;
  backdrop-filter: blur(12px);
}

.eyebrow {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--accent);
}

h1 {
  margin: 0;
  font-size: clamp(32px, 6vw, 44px);
  line-height: 1.05;
}

.intro {
  margin: 16px 0 0;
  font-size: 16px;
  line-height: 1.7;
  color: var(--muted);
}

.facts {
  margin: 28px 0 0;
  display: grid;
  gap: 14px;
}

.facts div {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 12px;
  padding: 14px 0;
  border-top: 1px solid rgba(15, 23, 42, 0.08);
}

.facts dt {
  font-size: 13px;
  color: var(--muted);
}

.facts dd {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
}

.actions {
  margin-top: 28px;
}

.button {
  width: 100%;
  border: 0;
  border-radius: 18px;
  padding: 16px 18px;
  font-size: 16px;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  cursor: pointer;
  transition: transform 140ms ease, opacity 140ms ease;
}

.button:hover:not(:disabled) {
  transform: translateY(-1px);
}

.button:disabled {
  cursor: wait;
  opacity: 0.6;
}

.status {
  min-height: 24px;
  margin: 14px 0 0;
  font-size: 14px;
  color: var(--muted);
}

.status.error {
  color: var(--danger);
}

.status.success {
  color: var(--accent-strong);
}

.tips {
  margin-top: 26px;
  padding: 18px;
  border-radius: 18px;
  background: rgba(15, 23, 42, 0.04);
}

.tips strong {
  display: block;
  margin-bottom: 8px;
}

.tips ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.7;
}

@media (max-width: 640px) {
  .panel {
    padding: 26px 20px;
    border-radius: 22px;
  }

  .facts div {
    grid-template-columns: 1fr;
    gap: 6px;
  }
}