/* Kleurenpalet */
:root {
  --primary: #4a90e2;
  --primary-light: #6cbaff;
  --secondary: #f0f4f8;
  --text: #2c3e50;
  --white: #ffffff;
  --radius: 12px;
  --shadow: rgba(0, 0, 0, 0.08);
  --max-width: 960px;
  --gradient: linear-gradient(to right, #4a90e2, #6cbaff);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--secondary);
  color: var(--text);
  line-height: 1.6;
  font-size: 1rem;
}

/* HEADER */
header {
  background: var(--gradient);
  color: var(--white);
  padding: 2rem 1rem;
  text-align: center;
  box-shadow: 0 2px 8px var(--shadow);
  border-bottom: 3px solid #3178c6;
}

header h1 {
  margin: 0;
  font-size: 2rem;
}

header h1 a {
  color: var(--white);
  text-decoration: none;
}

nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  padding: 0;
  margin: 1rem 0 0;
  gap: 0.5rem;
}

nav a {
  display: inline-block;
  color: var(--white);
  text-decoration: none;
  font-weight: 600;
  padding: 0.5rem 1rem;
  border-radius: var(--radius);
  transition: background 0.3s ease;
}

nav a:hover {
  background: rgba(255, 255, 255, 0.15);
}

/* MAIN CONTENT */
main {
  max-width: var(--max-width);
  margin: 2rem auto;
  padding: 2rem;
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: 0 4px 20px var(--shadow);
  animation: fadeIn 0.4s ease-in;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

section {
  margin-bottom: 2rem;
}

h2 {
  font-size: 1.6rem;
  margin-bottom: 1rem;
  border-left: 5px solid var(--primary);
  padding-left: 0.75rem;
  color: #264b7a;
  background: linear-gradient(to right, #e6f0fa, transparent);
  padding: 0.5rem 1rem;
  border-radius: var(--radius);
}

h3 {
  font-size: 1.2rem;
  margin-top: 1.5rem;
  color: #2a4d7c;
}

ul {
  padding-left: 1.5rem;
}

article {
  margin-bottom: 1.5rem;
  padding: 1rem;
  background: #f6faff;
  border-left: 4px solid var(--primary);
  border-radius: var(--radius);
  box-shadow: 0 2px 5px var(--shadow);
}

details summary {
  cursor: pointer;
  font-weight: bold;
  background: #eef5fc;
  padding: 0.75rem 1rem;
  border-radius: var(--radius);
  margin-bottom: 0.5rem;
  box-shadow: 0 1px 3px var(--shadow);
  transition: background 0.3s ease;
}

details summary:hover {
  background: #d6e9fc;
}

details p {
  margin: 0 1rem 1rem;
  padding: 0.5rem 1rem;
  background: #f8fbff;
  border-left: 3px solid var(--primary);
  border-radius: var(--radius);
}

/* IMAGES */
img {
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius);
  box-shadow: 0 2px 8px var(--shadow);
  margin: 1rem 0;
}

/* FOOTER */
footer {
  text-align: center;
  padding: 1.5rem;
  background: var(--secondary);
  font-size: 0.9rem;
  color: #666;
  border-top: 1px solid #ccc;
  margin-top: 3rem;
}

/* BUTTONS (optioneel) */
.button {
  background: var(--gradient);
  color: var(--white);
  padding: 0.75rem 1.25rem;
  text-decoration: none;
  display: inline-block;
  border-radius: var(--radius);
  box-shadow: 0 2px 6px var(--shadow);
  font-weight: bold;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.button:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 10px var(--shadow);
}

/* RESPONSIVE */
@media (max-width: 768px) {
  nav ul {
    flex-direction: column;
    gap: 0.25rem;
  }

  main {
    padding: 1rem;
  }

  header h1 {
    font-size: 1.5rem;
  }
}