:root {
    --bg-light: #fff8f8;      /* single light color everywhere */
    --text-light: #2b2b2b;
    --accent: #007acc;
    --sidebar-bg-light: #fff8f8;
  }
  
  /* Force light mode only */
  html, body {
    background: var(--bg-light);
    color: var(--text-light);
  }
  
  /* Base typography */
  body {
    margin: 0;
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-light);
    background: var(--bg-light);
  }
  
  /* Layout */
  .layout {
    display: flex;
    min-height: 100vh;
    justify-content: center; /* centers main content horizontally */
  }
  
  /* SIDEBAR */
  .sidebar {
    width: 260px;
    background: var(--sidebar-bg-light);
    padding: 1.8rem 1.25rem;
    position: sticky;
    top: 0;
    height: 100vh;
    box-sizing: border-box;
    margin-left: 6rem;      /* farther to the right */
    border-right: none;      /* removed the separating line */
    text-align: left;
  }
  
  /* Brand/title in sidebar */
 .sidebar .brand {
  display: inline-block;
  font-size: 1.3rem;
  font-family: "Roboto", sans-serif;
  letter-spacing: 0.01em;
  margin: 0 0 1rem 0;
  text-align: left;
  text-decoration: none; /* removes underline */
  cursor: pointer;
}


  
  /* Sidebar nav */
  .sidebar ul {
    list-style: none;
    padding: 0;
    margin: 0;
  }
  
  .sidebar li {
    margin: 0;
  }
  
  .sidebar li + li {
    margin-top: 0.25rem;
  }
  
  .sidebar a {
    display: block;
    text-decoration: none;
    color: var(--text-light);
    padding: 0.3rem 0;         /* vertical padding only */
    border-radius: 4px;
    font-size: 0.95rem;
    line-height: 1.35;
    text-align: left;
    font-weight: 0;
  }
  
.sidebar a:hover:not(.brand):not(.sidebar-title) {
  color: #0055bb;
}

  
  .sidebar a.active {
    color: var(--accent);
  }
  
  /* MAIN CONTENT */
  .content {
    flex: 1;
    padding: 3rem;
    padding-right: 12rem;
    max-width: 900px;
    margin: 0 auto;
    font-size: 1.05rem;
    background: var(--bg-light);
    text-align: left;
    align-self: flex-start; /* keeps natural top alignment */
  }
  
  .content header h1 {
    margin-top: 0;
    margin-bottom: 1.6rem;
    color: var(--accent);
    text-align: left;
  }
  
  /* Images / Figures */
  .img-center {
    text-align: center;
    margin: 2rem 0;
  }
  
  img {
    max-width: 100%;
    height: auto;
    border: none;
    border-radius: 0;
    box-shadow: none;
  }
  
  code {
    background: #f0f0f0;
    padding: 2px 5px;
    border-radius: 4px;
    font-family: monospace;
  }
  
  /* Footer */
  footer {
    text-align: center;
    margin-top: 4rem;
    padding-top: 1rem;
    border-top: 1px solid #e0dcdc;
    font-size: 0.9rem;
    opacity: 0.85;
  }
  
  /* Responsive */
  @media (max-width: 768px) {
    .layout {
      flex-direction: column;
      align-items: stretch;
    }
  
    .sidebar {
      width: 100%;
      height: auto;
      position: static;
      margin-left: 0;
      border-right: none;
      border-bottom: 1px solid #e6e2e2;
    }
  
    .content {
      margin-left: 0;
      padding: 1.5rem;
      max-width: 100%;
    }
  }

.inline_link,
.inline_link:hover,
.inline_link:active,
.inline_link:visited {
    color: #0000EE; /* Always blue, even after visit */
    text-decoration: none;
}

.note-box {
  background-color: #f5f5f5;       /* light gray */
  border-radius: 8px;
  padding: 1rem 1.5rem;
  margin: 1.5rem auto;
  text-align: center;
  max-width: 70%;                 /* narrower than main text */
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  font-style: italic;
  color: #333;
}