:root {
  --asphalt: #3b4146;
  --asphalt-deep: #2c3135;
  --marking: #f4f4f0;
  --teal: #1f9b8e;
  --blue: #2a64ad;
  --error: #b3261e;
  --paper: #f6f7f7;
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, Cantarell, "Noto Sans", sans-serif;
  background: var(--asphalt);
  color: var(--asphalt-deep);
}
.page {
  min-height: 100%;
  display: grid;
  grid-template-columns: 1fr minmax(320px, 420px) 1fr;
  align-items: center;
  position: relative;
  overflow: hidden;
}
/* Linea di mezzeria: l'unico elemento decorativo */
.lane {
  position: absolute;
  top: 0; bottom: 0;
  left: calc(50% - 250px);
  width: 10px;
  background: repeating-linear-gradient(to bottom, var(--marking) 0 48px, transparent 48px 96px);
  opacity: .55;
}
.panel {
  grid-column: 2;
  background: var(--paper);
  padding: 40px 36px 28px;
  border-radius: 4px;
  position: relative;
}
h1 {
  margin: 0 0 6px;
  font-size: 1.75rem;
  letter-spacing: .02em;
  color: var(--asphalt-deep);
}
.intro { margin: 0 0 24px; line-height: 1.45; color: #4d555b; }
label { display: block; font-size: .9rem; font-weight: 600; margin: 16px 0 6px; }
input {
  width: 100%;
  padding: 11px 12px;
  font: inherit;
  border: 1px solid #b9c0c4;
  border-radius: 3px;
  background: #fff;
}
input:focus-visible, button:focus-visible { outline: 3px solid var(--blue); outline-offset: 2px; }
button {
  margin-top: 24px;
  width: 100%;
  padding: 12px;
  font: inherit;
  font-weight: 600;
  color: #fff;
  background: var(--teal);
  border: 0;
  border-radius: 3px;
  cursor: pointer;
}
button:hover { background: #18877b; }
.error {
  margin: 0 0 8px;
  padding: 10px 12px;
  border-left: 4px solid var(--error);
  background: #fbeceb;
  color: var(--error);
}
.footer { margin: 28px 0 0; font-size: .8rem; color: #7a8388; }
@media (max-width: 720px) {
  .page { grid-template-columns: 16px 1fr 16px; }
  .lane { left: 24px; }
  .panel { padding: 32px 22px 22px; }
}