* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: Arial, sans-serif; line-height: 1.6; background: #f9f9f9; color: #333; }
.container { max-width: 1200px; margin: auto; padding: 20px; }

header { text-align: center; margin-bottom: 30px; }
header h1 { font-size: 2em; }
nav { display: flex; flex-wrap: wrap; justify-content: center; margin-bottom: 20px; }
nav a { margin: 5px 10px; text-decoration: none; color: #0066cc; padding: 8px 12px; border-radius: 4px; transition: background 0.3s; }
nav a:hover { background: rgba(0, 102, 204, 0.1); }

.section-row { display: flex; align-items: flex-start; flex-wrap: wrap; margin-bottom: 40px; }
.section-row.reverse { flex-direction: row-reverse; }
.img-wrapper, .text-wrapper { flex: 1; padding: 10px; }

.paired-images img {
  flex: 1;
}
.paired-images img {
  flex: 1;
  max-width: 32%;
}
.paired-images { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 10px; }
.paired-images img { flex: 1; }
.paired-images img.small-chart { flex: 0 0 40%; }

section h2 { font-size: 1.4em; margin-bottom: 10px; }
section img { width: 100%; height: auto; border: 1px solid #ddd; background: #fff; }
.explanation { margin-top: 10px; }

#theme-toggle { position: fixed; top: 20px; right: 20px; padding: 8px 12px; cursor: pointer; background: #fff; border: 1px solid #ccc; border-radius: 4px; }

body.dark { background: #222; color: #ddd; }
body.dark a { color: #66aaff; }
body.dark img { background: #333; border-color: #444; }
body.dark #theme-toggle { background: #333; color: #ddd; border-color: #555; }

@media (max-width: 992px) {
  .section-row {
    flex-direction: column;
  }
  .img-wrapper, .text-wrapper {
    width: 100%;
    padding: 5px 0;
  }
  .paired-images {
    gap: 8px;
  }
  .paired-images img {
    max-width: 48%;
  }
}

@media (max-width: 576px) {
  nav {
    flex-direction: column;
    align-items: stretch;
  }
  nav a {
    flex: none;
    margin: 5px 0;
  }
  .paired-images {
    flex-direction: column;
  }
  .paired-images img {
    max-width: 100%;
  }
  .img-wrapper, .text-wrapper {
    padding: 5px;
  }
}