:root {
  --navy: #0B1B3F;
  --indigo: #2D2A7E;
  --magenta: #C2185B;
  --white: #FFFFFF;
  --text-dark: #1E2A38;
  --bg-light: #F5F7FA;
  --radius: 8px;
  --font: Inter, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
}

/* Base */
html, body {
  font-family: var(--font);
  background: var(--bg-light);
  color: var(--text-dark);
  margin: 0;
  padding: 0;
}

/* Header */
header {
  position: sticky;
  top: 0;
  width: 100%;
  background: linear-gradient(135deg, var(--navy) 0%, var(--indigo) 48%, var(--magenta) 100%);
  color: var(--white);
  text-align: center;
  padding: 16px;
  z-index: 1000;
}
header img {
  width: 64px;
  display: block;
  margin: 0 auto 8px;
}
header h1 {
  margin: 0;
  font-size: 24px;
  font-weight: 700;
}

/* Container */
.container {
  max-width: 900px;
  margin: 20px auto;
  padding: 0 16px;
}

/* Cards */
.cb-card {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  padding: 20px;
  margin-bottom: 16px;
}
.cb-card h2 {
  margin-top: 0;
  color: var(--navy);
}

/* Form elements */
.form-row {
  margin-bottom: 12px;
}
label {
  display: block;
  margin-bottom: 4px;
  font-weight: 600;
}
input[type="text"],
input[type="url"],
input[type="number"],
select,
textarea {
  width: 100%;
  padding: 8px;
  border: 1px solid #ccc;
  border-radius: var(--radius);
  font-size: 14px;
}

/* Buttons */
button,
.btn-primary {
  background: linear-gradient(90deg, var(--navy), var(--magenta));
  color: var(--white);
  border: none;
  border-radius: var(--radius);
  padding: 10px 16px;
  cursor: pointer;
  font-size: 16px;
}
button:hover {
  filter: brightness(1.06);
}

/* Radio and checkbox groups */
.radio-group,
.checkbox-group {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}
.radio-group label,
.checkbox-group label {
  font-weight: normal;
}

/* Responsive tweaks */
@media (max-width: 640px) {
  .cb-card {
    padding: 16px;
  }
  .radio-group,
  .checkbox-group {
    flex-direction: column;
    gap: 8px;
  }
}