body { overflow-x:hidden; }
.sidebar { height:100vh; position:fixed; width:260px; }
.content { margin-left:270px; padding:24px; }
pre[class*="language-"] { border-radius:8px; }
.code-block { position: relative; }
.copy-btn {
  position:absolute; right:10px; top:10px;
  font-size:12px; padding:4px 8px; border-radius:6px;
}
.nav-link.active { font-weight:600; text-decoration: underline; }