:root {
  --bg-light: #ffffff;
  --bg-dark: #121212;
  --text-light: #121212;
  --text-dark: #ffffff;
  --accent: #5A9;
  --focus-outline: 3px dashed #5A9;
  font-size: 100%;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: 'Open Sans', sans-serif;
  background-color: var(--bg-light);
  color: var(--text-light);
  line-height: 1.6;
  padding-top: 0px;
}
body.dark-mode { background-color: var(--bg-dark); color: var(--text-dark); }
body.dyslexic-mode { font-family: 'OpenDyslexic', Arial, sans-serif; }
body.high-contrast { background-color: #000000; color: #FFFF00; }

header, main, footer {
  padding: 1.5rem;
  max-width: 900px;
  margin: auto;
}
.skip-link {
  position: absolute;
  left: -999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
}
.skip-link:focus {
  position: static;
  width: auto;
  height: auto;
  padding: 1rem;
  background: #000;
  color: #fff;
  z-index: 1000;
}
.top-toolbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: #f4f4f4;
  border-bottom: 1px solid #ccc;
  padding: 0.5rem 1rem;
  z-index: 1000;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: flex-start;
  align-items: flex-start;
}
.ribbon-group {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.25rem;
}
.ribbon-label {
  font-size: 0.75rem;
  font-weight: bold;
  text-transform: uppercase;
  color: #444;
  margin-bottom: 0.25rem;
}
.ribbon-group button,
.ribbon-group select {
  padding: 0.4rem;
  font-size: 0.9rem;
  border: none;
  border-radius: 4px;
  background: #eee;
  cursor: pointer;
  min-width: 36px;
  text-align: left;
}
button:focus,
a:focus,
.ribbon-group button:focus,
.ribbon-group select:focus,
.top-toolbar button:focus,
.top-toolbar select:focus {
  outline: var(--focus-outline);
}

button.feature-toggle.active-feature {
  border: 2px solid #4CAF50;
  background-color: #e7f9ee;
  font-weight: bold;
}

@media (max-width: 768px) {
  .top-toolbar {
    flex-direction: column;
    align-items: flex-start;
    overflow-x: auto;
  }
  .ribbon-group {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
  }
  .ribbon-label { width: 100%; }
  .ribbon-group button,
  .ribbon-group select {
    font-size: 0.8rem;
  }
  header, main, footer { padding: 1rem; }
}