body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f4f7fb;
  color: #1f2937;
}

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 24px;
}

.card {
  background: #ffffff;
  border-radius: 14px;
  padding: 20px;
  margin-bottom: 20px;
  box-shadow: 0 6px 20px rgba(0,0,0,0.08);
}

.auth-card {
  max-width: 420px;
  margin: 60px auto;
}

h1, h2, h3 {
  margin-top: 0;
}

label {
  display: block;
  margin-top: 12px;
  margin-bottom: 6px;
  font-weight: bold;
}

input {
  width: 100%;
  box-sizing: border-box;
  padding: 12px;
  border: 1px solid #d1d5db;
  border-radius: 10px;
}

button, .logout-btn {
  display: inline-block;
  padding: 12px 16px;
  margin-top: 14px;
  border: none;
  border-radius: 10px;
  background: #2563eb;
  color: #fff;
  text-decoration: none;
  cursor: pointer;
}

button:hover, .logout-btn:hover {
  opacity: 0.92;
}

.alert {
  padding: 12px 14px;
  border-radius: 10px;
  margin: 14px 0;
}

.alert.success {
  background: #dcfce7;
  color: #166534;
}

.alert.error {
  background: #fee2e2;
  color: #991b1b;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  margin-bottom: 24px;
}

.device-form {
  display: grid;
  grid-template-columns: 1fr 1fr auto;
  gap: 12px;
  align-items: end;
}

.form-group {
  display: flex;
  flex-direction: column;
}

.device-list {
  display: grid;
  gap: 16px;
}

.device-item {
  border: 1px solid #e5e7eb;
  border-radius: 12px;
  padding: 16px;
  background: #fafafa;
}

.device-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 12px;
}

.btn.small {
  padding: 10px 12px;
  margin-top: 0;
}

.btn.danger {
  background: #dc2626;
}

.btn.delete {
  background: #6b7280;
}

.auth-link {
  margin-top: 16px;
}

@media (max-width: 768px) {
  .device-form {
    grid-template-columns: 1fr;
  }

  .topbar {
    flex-direction: column;
    align-items: flex-start;
  }
}