.diag {
  padding: 48px 16px;
  background: #07111f;
  color: #fff;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.diag-card {
  max-width: 680px;
  margin: 0 auto;
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.14);
  border-radius: 24px;
  padding: 32px;
  box-shadow: 0 20px 60px rgba(0,0,0,.25);
}

.diag-progress {
  width: 100%;
  height: 8px;
  background: rgba(255,255,255,.12);
  border-radius: 99px;
  overflow: hidden;
  margin-bottom: 20px;
}

#diagProgressBar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #19c37d, #00a3ff);
  transition: width .25s ease;
}

.diag-step {
  font-size: 14px;
  opacity: .7;
  margin-bottom: 12px;
}

#diagTitle {
  font-size: clamp(28px, 5vw, 44px);
  line-height: 1.05;
  margin: 0 0 12px;
}

.diag-subtitle {
  font-size: 18px;
  opacity: .82;
  margin-bottom: 28px;
}

.diag-options {
  display: grid;
  gap: 12px;
}

.diag-option {
  width: 100%;
  padding: 18px 20px;
  border-radius: 16px;
  border: 1px solid rgba(255,255,255,.18);
  background: rgba(255,255,255,.08);
  color: #fff;
  font-size: 17px;
  text-align: left;
  cursor: pointer;
  transition: transform .15s ease, background .15s ease;
}

.diag-option:hover {
  background: rgba(255,255,255,.14);
  transform: translateY(-1px);
}

.diag-back {
  margin-top: 24px;
  background: transparent;
  border: none;
  color: rgba(255,255,255,.7);
  cursor: pointer;
  font-size: 15px;
  display: none;
}

.diag-back:hover {
  color: #fff;
}

@media (max-width: 600px) {
  .diag-card {
    padding: 24px 18px;
    border-radius: 20px;
  }

  .diag-option {
    font-size: 16px;
    padding: 16px;
  }
}