.side { position: fixed; top: 1rem; left: 1rem; z-index: 10; font-size: 0.95rem; }
.side summary { width: fit-content; list-style: none; cursor: pointer; color: #888; font-size: 2rem; line-height: 1; padding: 0.3rem 0.55rem; border-radius: 6px; }
.side summary::-webkit-details-marker { display: none; }
.side summary:hover, .side summary:focus { color: #222; background: #f2f2f2; }
.side > ul { margin: 0.4rem 0 0; padding: 0.6rem 0.9rem; background: #fff; border: 1px solid #e5e5e5; border-radius: 8px; box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08); }
.side ul { list-style: none; }
.side ul ul { margin: 0.2rem 0 0; padding: 0 0 0 1rem; font-size: 0.9rem; }
.side li { margin: 0.3rem 0; }
.side a { color: #555; text-decoration: none; }
.side a:hover, .side a:focus { color: #222; text-decoration: underline; }
.side .sep { margin: 0.5rem 0; border-top: 1px solid #e5e5e5; }
.side .sub > a::after { content: " \25B8"; color: #999; font-size: 0.8rem; }
.side .sub > ul { display: none; }
.side .sub:hover > ul, .side .sub:focus-within > ul { display: block; }