body {
  margin: 0;
  background: #f8fafc;
  font-family: "Noto Sans KR", sans-serif;
  color: #1e293b;
}

.device-guide-box {
  max-width: 900px;
  margin: 40px auto;
  padding: 24px;
}

.device-guide-box h2 {
  text-align: center;
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 28px;
  color: #0f172a;
}

.guide-card {
  background: #ffffff;
  border: 1px solid #e5e7eb;
  border-radius: 18px;
  padding: 24px;
  margin-bottom: 18px;
  box-shadow: 0 8px 22px rgba(15, 23, 42, 0.05);
}

.guide-card h3 {
  font-size: 1.15rem;
  font-weight: 800;
  color: #2563eb;
  margin-bottom: 12px;
}

.guide-card p,
.guide-card li {
  font-size: 0.96rem;
  line-height: 1.75;
  color: #334155;
}

.guide-card ul {
  padding-left: 20px;
  margin-bottom: 0;
}

.guide-note {
  margin-top: 12px;
  color: #64748b !important;
  font-size: 0.9rem !important;
}

.login-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.login-grid > div {
  background: #f8fafc;
  border-radius: 14px;
  padding: 16px;
}

.login-grid strong {
  display: block;
  margin-bottom: 8px;
  color: #0f172a;
}

.guide-card.warning {
  background: #fff7f7;
  border-color: #fecaca;
}

.guide-card.warning h3 {
  color: #b91c1c;
}

.guide-card.confirm {
  background: #eff6ff;
  border-color: #bfdbfe;
}

.guide-action {
  margin-top: 28px;
  text-align: center;
}

.guide-action .btn,
.btn-primary {
  min-width: 220px;
  padding: 12px 20px;
  border: none;
  border-radius: 12px;
  background: #2563eb;
  color: #ffffff;
  font-weight: 700;
  cursor: pointer;
}

.guide-action .btn:hover,
.btn-primary:hover {
  background: #1d4ed8;
}

@media (max-width: 768px) {
  .device-guide-box {
    margin: 20px 12px;
    padding: 16px;
  }

  .device-guide-box h2 {
    font-size: 1.45rem;
  }

  .login-grid {
    grid-template-columns: 1fr;
  }
}