body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  box-sizing: border-box;
  text-align: center;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: #0f1311;
  color: #f2f5f3;
}
main { max-width: 420px; }
.icon { font-size: 48px; }
h1 { font-size: 22px; margin: 16px 0 8px; }
p { color: #b8c2bd; line-height: 1.5; }
.hint { font-size: 13px; margin-top: 24px; }
.btn {
  display: inline-block;
  margin-top: 20px;
  padding: 14px 24px;
  border-radius: 12px;
  background: #164c3f;
  color: #fff;
  font-weight: 600;
  text-decoration: none;
}