:root {
  --lavagna: #181c25;
  --blu: #5c78a6;
  --rosso: #cc0000;
  --bianco: #ffffff;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; }
body {
  display: flex;
  flex-direction: column;
  background: var(--lavagna);
  background-image: radial-gradient(ellipse at center, #2a3040 0%, var(--lavagna) 75%);
  color: var(--bianco);
  font-family: Arial, Helvetica, sans-serif;
}
.box {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 40px 16px;
  text-align: center;
}
.logo { max-width: 100%; height: auto; margin-bottom: 36px; }
.card {
  width: 100%;
  max-width: 620px;
  background: var(--bianco);
  color: var(--lavagna);
  border-radius: 6px;
  padding: 40px 24px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, .45);
}
h1 {
  font-size: clamp(26px, 5vw, 40px);
  font-weight: 700;
  margin-bottom: 14px;
}
.card p { font-size: 18px; color: var(--blu); }
.card::after {
  content: "";
  display: block;
  width: 70px;
  height: 4px;
  background: var(--rosso);
  margin: 22px auto 0;
  border-radius: 2px;
}
footer {
  text-align: center;
  font-size: 13px;
  color: var(--blu);
  padding: 14px 16px;
}