:root {
  --primary-color: #001f3f; /* Deep Navy - Authority */
  --secondary-color: #0070ba; /* Trust-Blue - Payment/CTA */
  --accent-color: #7FDBFF; /* Soft Blue - Highlights */
  --bg-color: #f8f9fa; /* Soft White/Neutral Slate - Modern Professional */
  --text-color: #333333; /* Dark Slate - Readability */
  --secondary-bg: #ffffff; /* Card/Container BG */
  --border-color: #dddddd;
  --font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --nav-bg: #001f3f;
  --nav-text: #ffffff;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
  font-size: 16px;
}

a {
  color: var(--secondary-color);
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  color: var(--primary-color);
  text-decoration: underline;
}

/* Header & Nav */
header {
  background-color: var(--secondary-bg);
  border-bottom: 1px solid var(--border-color);
  padding: 1.5rem 0;
  text-align: center;
}

.logo {
  font-size: 2rem;
  font-weight: bold;
  text-transform: uppercase;
  color: var(--primary-color);
  letter-spacing: 1px;
}

.tagline {
  font-size: 1rem;
  color: #666;
  margin-top: 0.5rem;
}

nav {
  background-color: var(--nav-bg);
  padding: 0.8rem 0;
  text-align: center;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.5rem;
  padding: 0 1rem;
}

nav a {
  color: var(--nav-text);
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.9rem;
  padding: 0.5rem;
  letter-spacing: 0.5px;
}

nav a:hover {
  color: var(--accent-color);
  text-decoration: none;
}

/* Layout */
main {
  padding: 2rem 1rem;
  max-width: 900px; /* Optimal reading width */
  margin: 0 auto;
}

/* Typography Hierarchy */
h1, h2, h3 {
  color: var(--primary-color);
  margin-bottom: 1rem;
  line-height: 1.3;
}

h1 {
  font-size: 2.5rem;
  font-weight: 700;
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 1rem;
  margin-bottom: 2rem;
}

h2 {
  font-size: 1.8rem;
  font-weight: 600;
  margin-top: 2.5rem;
  border-left: 4px solid var(--secondary-color);
  padding-left: 1rem;
}

h3 {
  font-size: 1.4rem;
  font-weight: 500;
  margin-top: 1.5rem;
}

p {
  margin-bottom: 1.2rem;
  font-size: 1.1rem; /* Slightly larger for readability */
}

ul, ol {
  margin-bottom: 1.2rem;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.5rem;
}

/* Ad Containers (CLS Protection) */
.ad-container-leaderboard {
  width: 100%;
  min-height: 90px; /* Standard leaderboard height */
  background-color: #f1f1f1;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 2rem 0;
  overflow: hidden; /* Prevent overflow */
}

.ad-container-responsive {
  width: 100%;
  min-height: 250px; /* Approximate height for responsive square */
  background-color: #f1f1f1;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 2rem 0;
}

/* Buttons & CTA */
.btn {
  display: inline-block;
  background-color: var(--primary-color);
  color: #fff;
  padding: 1rem 2rem;
  text-transform: uppercase;
  font-weight: bold;
  border: none;
  cursor: pointer;
  transition: background-color 0.3s ease;
  text-align: center;
  border-radius: 4px;
  min-width: 44px; /* Touch target law */
  min-height: 44px;
}

.btn:hover {
  background-color: #003366;
  text-decoration: none;
  color: #fff;
}

.btn-payment {
  background-color: var(--secondary-color); /* Trust-Blue #0070ba */
  color: #fff;
  padding: 1rem 2rem;
  font-weight: bold;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  transition: background-color 0.3s ease;
  text-align: center;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 44px; /* Touch target law */
  min-height: 44px;
  margin-top: 1rem;
  box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.btn-payment:hover {
  background-color: #005a9e;
  text-decoration: none;
  color: #fff;
}

/* Cards */
.card {
  background-color: var(--secondary-bg);
  padding: 2rem;
  margin-bottom: 2rem;
  border: 1px solid var(--border-color);
  border-radius: 4px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.pillar-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

/* Footer */
.footer {
  background-color: var(--nav-bg);
  color: #ccc;
  padding: 3rem 1rem;
  text-align: center;
  font-size: 0.9rem;
  margin-top: 4rem;
}

.footer a {
  color: var(--accent-color);
}

.disclaimer {
  max-width: 800px;
  margin: 0 auto 1.5rem;
  font-style: italic;
  opacity: 0.8;
}

/* Monetization / Support Sections */
.support-section {
  background-color: #e8f4fd; /* Very light blue tint */
  padding: 2rem;
  border-radius: 4px;
  text-align: center;
  margin: 3rem 0;
  border: 1px solid #bce0fd;
}

.support-section h3 {
  color: var(--primary-color);
  margin-top: 0;
}

.microcopy {
  font-size: 0.9rem;
  color: #555;
  margin-bottom: 1rem;
}

/* Quiz Styles */
.quiz-container {
  background-color: var(--secondary-bg);
  padding: 2.5rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

.question {
  margin-bottom: 2rem;
  border-bottom: 1px solid #eee;
  padding-bottom: 1.5rem;
}

.options label {
  display: block;
  margin-bottom: 0.8rem;
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 4px;
  transition: background-color 0.2s ease;
}

.options label:hover {
  background-color: #f0f0f0;
}

.result {
  margin-top: 2rem;
  padding: 1.5rem;
  background-color: #e8f4fd;
  border: 1px solid #bce0fd;
  border-radius: 4px;
  display: none;
}

/* Responsive adjustments */
@media (max-width: 600px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }
  nav ul { gap: 0.8rem; }
  .pillar-grid { grid-template-columns: 1fr; }
  main { padding: 1.5rem 1rem; }
}