feat: add line numbers to code blocks, enhance search overlay functionality, and improve navbar search visibility

css/style.css

@@ -1862,6 +1862,22 @@ pre code.hljs {
 	background: transparent !important;
 }
 
+/* Line numbers (highlightjs-line-numbers plugin builds a table inside <code>) */
+.hljs-ln { border-collapse: collapse; }
+.hljs-ln td { padding: 0; border: 0; vertical-align: top; }
+.hljs-ln-numbers {
+	width: 1%;
+	white-space: nowrap;
+	text-align: right;
+	padding-right: 0.9em !important;
+	color: var(--text-muted);
+	border-right: 1px solid var(--border-color);
+	user-select: none;
+	-webkit-user-select: none;
+}
+.hljs-ln-code { padding-left: 0.9em !important; }
+.hljs-ln-n::before { content: attr(data-line-number); }
+
 /* ========================================
    ANCHOR OFFSET — clear the fixed navbar on ToC / hash jumps
    Without this, jumping to a heading lands it at y=0, hidden behind the
@@ -2277,11 +2293,21 @@ button:focus:not(:focus-visible) {
 	box-shadow: var(--shadow-lg);
 }
 
-.search-input {
-	width: 100%;
-	padding: 1rem 1.2rem;
-	border: none;
+.search-field {
+	display: flex;
+	align-items: center;
+	gap: 0.6rem;
+	padding: 0 1.1rem;
 	border-bottom: 1px solid var(--border-color);
+}
+
+.search-icon { flex: 0 0 auto; color: var(--text-muted); }
+
+.search-input {
+	flex: 1;
+	min-width: 0;
+	padding: 0.95rem 0;
+	border: none;
 	background: transparent;
 	color: var(--text-primary);
 	font-family: var(--font-sans);
@@ -2291,6 +2317,30 @@ button:focus:not(:focus-visible) {
 
 .search-input::placeholder { color: var(--text-muted); }
 
+.search-hint {
+	display: flex;
+	align-items: center;
+	gap: 0.25rem;
+	padding: 0.5rem 1.1rem;
+	border-top: 1px solid var(--border-subtle);
+	font-size: var(--font-size-xs);
+	color: var(--text-muted);
+}
+
+.search-hint kbd {
+	padding: 0.05em 0.4em;
+	font-family: var(--font-sans);
+	font-size: 0.95em;
+	color: var(--text-secondary);
+	background: var(--bg-subtle);
+	border: 1px solid var(--border-color);
+	border-radius: 4px;
+}
+
+/* Navbar search button — hidden until JS reveals it (no on-page search in view) */
+.nav-search { display: none; }
+.nav-search.is-visible { display: block; }
+
 .search-results {
 	list-style: none;
 	margin: 0;