/*
  ========================================
  STYLE.CSS for Target-Insight & Advertation
  ========================================
*/

/* 1. VARIABLES & GLOBAL STYLES */
:root {
  --background-color: #121212;
  --surface-color: #1e1e1e;
  --primary-text-color: #e0e0e0;
  --secondary-text-color: #a0a0a0;
  --accent-color: #03dac6;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

body {
  font-family: var(--font-family);
  background-color: var(--background-color);
  color: var(--primary-text-color);
  line-height: 1.6;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* 2. LAYOUT & STRUCTURE */
header, main, footer {
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
}

main { flex-grow: 1; }

/* 3. TYPOGRAPHY */
h1 {
  font-size: 2.5rem;
  color: var(--primary-text-color);
  margin-bottom: 20px;
  border-bottom: 2px solid var(--accent-color);
  padding-bottom: 10px;
}

h2 {
  font-size: 1.8rem;
  color: var(--primary-text-color);
  margin-top: 40px;
  margin-bottom: 15px;
}

p {
  font-size: 1.1rem;
  margin-bottom: 20px;
  color: var(--secondary-text-color);
}

strong { color: var(--accent-color); }

/* 4. HEADER & NAVIGATION */
header { padding-top: 40px; padding-bottom: 40px; }
nav { display: flex; justify-content: center; gap: 30px; }
nav a {
  color: var(--secondary-text-color);
  text-decoration: none;
  font-size: 1.1rem;
  font-weight: bold;
  padding: 5px 10px;
  border-radius: 5px;
  transition: background-color 0.3s, color 0.3s;
}
nav a:hover { color: var(--primary-text-color); background-color: var(--surface-color); }

/* 5. LINKS & BUTTONS */
a { color: var(--accent-color); text-decoration: none; }
a:hover { text-decoration: underline; }

.cta-button {
  display: inline-block;
  background-color: var(--accent-color);
  color: var(--background-color);
  padding: 15px 30px;
  font-size: 1.2rem;
  font-weight: bold;
  text-decoration: none;
  border-radius: 8px;
  margin-top: 20px;
  transition: transform 0.2s, box-shadow 0.2s;
}
.cta-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 10px rgba(3, 218, 198, 0.3);
  text-decoration: none;
}

/* 6. FOOTER */
footer { text-align: center; padding: 20px; margin-top: 40px; color: var(--secondary-text-color); font-size: 0.9rem; }

/* 7. RESPONSIVE DESIGN (For Mobile) */
@media (max-width: 768px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }
  p, nav a { font-size: 1rem; }
  nav { flex-direction: column; align-items: center; gap: 15px; }
}